Low and very low birth weight in infants conceived with use of assisted reproductive technology

miRNAs in Follicular and Oviductal Fluids Support Global DNA Demethylation in Early-Stage Embryos

Global methylation levels differ in in vitro- and in vivo-developed embryos. Follicular fluid (FF) contains extracellular vesicles (EVs) containing miRNAs that affect embryonic development. Here, we examined our hypothesis that components in FF affect global DNA methylation and embryonic development. Oocytes and FF were collected from bovine ovaries. Treatment of zygotes with a low concentration of FF induced global DNA demethylation, improved embryonic development, and reduced DNMT1/3A levels. We show that embryos take up EVs containing labeled miRNA secreted from granulosa cells and the treatment of zygotes with EVs derived from FF reduces global DNA methylation in embryos. Furthermore, the methylation levels of in vitro-developed blastocysts were higher than those of in their vivo counterparts. Based on small RNA-sequencing and in silico analysis, we predicted miR-29b, -199a-3p, and -148a to target DNMTs and to induce DNA demethylation, thereby improving embryonic development. Moreover, among FF from 30 cows, FF with a high content of these miRNAs demethylated more DNA in the embryos than FF with a lower miRNA content. Thus, miRNAs in FF play a role in early embryonic development.

Comprehensive appraisal of pregnancy and neonatal outcomes in singleton pregnancies conceived via in vitro fertilization in the USA (2016-2021)

OBJECTIVES

We set out to compare adverse pregnancy and neonatal outcomes in singleton gestations conceived via in vitro fertilization (IVF) to those conceived spontaneously.

METHODS

Retrospective, population-based cohort using the CDC Natality Live Birth database (2016-2021). All singleton births were stratified into two groups: those conceived via IVF, and those conceived spontaneously. The incidence of several adverse pregnancy and neonatal outcomes was compared between the two groups using Pearson's chi-square test with Bonferroni adjustments. Multivariate logistic regression was used to adjust outcomes for potential confounders.

RESULTS

Singleton live births conceived by IVF comprised 0.86 % of the cohort (179,987 of 20,930,668). Baseline characteristics varied significantly between the groups. After adjusting for confounding variables, pregnancies conceived via IVF were associated with an increased risk of several adverse pregnancy and neonatal outcomes compared to those conceived spontaneously. The maternal adverse outcomes with the highest risk in IVF pregnancies included maternal transfusion, unplanned hysterectomy, and maternal intensive care unit admission. Increased rates of hypertensive disorder of pregnancy, preterm birth (delivery <37 weeks of gestation), and cesarean delivery were also noted. The highest risk neonatal adverse outcomes associated with IVF included immediate and prolonged ventilation, neonatal seizures, and neonatal intensive care unit admissions, among others.

CONCLUSIONS

Based on this large contemporary United States cohort, the risk of several adverse pregnancy and neonatal outcomes is increased in singleton pregnancies conceived via IVF compared to those conceived spontaneously. Obstetricians should be conscious of these associations while caring for and counseling pregnancies conceived via IVF.

Epigenetic variation in neonatal tissues in infants conceived using capacitation-in vitro maturation vs. in vitro fertilization

OBJECTIVE

To investigate alterations of the global DNA methylation profile in placenta, cord blood, and neonatal buccal smears in infants conceived using in vitro maturation (IVM) with a prematuration step (capacitation-IVM [CAPA-IVM]) vs. in vitro fertilization (IVF).

DESIGN

Analysis of data from the offspring of participants in a randomized controlled trial.

SETTING

Private clinic.

PATIENTS

Forty-six women with polycystic ovary syndrome and/or high antral follicle count and their offspring (58 newborns).

INTERVENTION(S)

Women with polycystic ovary syndrome and/or a high antral follicle count participating in the clinical trial were randomized to undergo CAPA-IVM or conventional IVF.

MAIN OUTCOME MEASURE(S)

At delivery, biological samples including cord blood, placental tissue, and a neonatal buccal smear were collected. Genome-wide DNA methylation was determined using the Illumina Infinium MethylationEPIC BeadChip. Variability in methylation was also considered, and mean variances for the two treatment categories were compared.

RESULTS

In neonatal buccal smears, there were no significant differences between the CAPA-IVM and conventional IVF groups on the basis of the CpG probe after linear regression analysis using a significant cut-off of false-discovery rate <0.05 and |Δβ|≥0.05. In cord blood, only one CpG site showed a significant gain of methylation in the CAPA-IVM group. In the placenta, CAPA-IVM was significantly associated with changes in methylation at five CpG sites. Significantly more variable DNA methylation was found in five probes in the placenta, 54 in cord blood, and two in buccal smears after IVM of oocytes. In cord blood samples, 20 CpG sites had more variable methylation in the conventional IVF vs. IVM group. Isolated CpG sites showing differences in methylation in cord blood were not associated with changes in gene expression of the overlapping genes.

CONCLUSION(S)

Capacitation-IVM appeared to be associated with only a small amount of epigenetic variation in cord blood, placental tissue, and neonate buccal smears.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03405701 (www.

CLINICALTRIALS

gov).

Long-term health risk of offspring born from assisted reproductive technologies

Since the world's first in vitro fertilization baby was born in 1978, there have been more than 8 million children conceived through assisted reproductive technologies (ART) worldwide, and a significant proportion of them have reached puberty or young adulthood. Many studies have found that ART increases the risk of adverse perinatal outcomes, including preterm birth, low birth weight, small size for gestational age, perinatal mortality, and congenital anomalies. However, data regarding the long-term outcomes of ART offspring are limited. According to the developmental origins of health and disease theory, adverse environments during early life stages may induce adaptive changes and subsequently result in an increased risk of diseases in later life. Increasing evidence also suggests that ART offspring are predisposed to an increased risk of non-communicable diseases, such as malignancies, asthma, obesity, metabolic syndrome, diabetes, cardiovascular diseases, and neurodevelopmental and psychiatric disorders. In this review, we summarize the risks for long-term health in ART offspring, discuss the underlying mechanisms, including underlying parental infertility, epigenetic alterations, non-physiological hormone levels, and placental dysfunction, and propose potential strategies to optimize the management of ART and health care of parents and children to eliminate the associated risks. Further ongoing follow-up and research are warranted to determine the effects of ART on the long-term health of ART offspring in later life.

How does the need for IVF affect pregnancy complications among multiple gestations? The study of a large American population database including almost 100,000 multiple gestations

Objective

This study's aim is to compare pregnancy outcomes in multifetal gestations that were conceived spontaneously compared to in vitro fertilization (IVF). Few population-based studies have addressed this topic.

Study design

This is a retrospective cohort study using the Health Care Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS) database. Our study cohort included 90,552 multifetal gestations conceived spontaneously and 3219 IVF conceptions, from 2008 to 2014, inclusively. Multivariate logistic regression analyses were performed comparing maternal and neonatal outcomes, whilst adjusting for confounding variables. Subject was conducted using ICD-9 codes for multifetal gestation: 651. X and 76.1 and ICD-9 code for IVF: 23.85. Each pregnancy was included once.

Results and conclusion

IVF multifetal gestations had increased risk of pregnancy-induced hypertension (aOR 1.31, 95 % CI 1.20-1.43), gestational hypertension (aOR 1.21, 95 % CI 1.04-1.41), preeclampsia (aOR 1.31, 95 % CI 1.19-1.45), gestational diabetes (aOR 1.26, 95 % CI 1.13-1.41) and placenta previa (aOR 1.7, 95 % CI 1.32-2.19). IVF delivery outcomes were more likely complicated by cesarean section (aOR 1.21, 95 % CI 1.10-1.33), preterm premature rupture of membranes (aOR 1.33, 95 % CI 1.16-1.52), chorioamnionitis (aOR 1.71, 95 % CI 1.37-2.14), postpartum hemorrhage (aOR 1.44, 95 % CI 1.26-1.63) and transfusions (aOR 1.48, 95 %CI 1.26-1.74). IVF neonatal outcomes were more likely complicated by small for gestational age (aOR 1.26, 95 % CI 1.12-1.41) and congenital anomalies (aOR 1.82, 95 % CI 1.29-2.57). IVF was not found to increase risks of eclampsia, preterm delivery, operative vaginal delivery, hysterectomy, or intrauterine fetal demise.IVF increased the risk of pregnancy, delivery, and neonatal outcomes in multifetal pregnancies with risks increased from 20 % to 70 %. The role of infertility versus the need for IVF and the type of IVF protocol used should be further evaluated.

High estrogen during ovarian stimulation induced loss of maternal imprinted methylation that is essential for placental development via overexpression of TET2 in mouse oocytes

BACKGROUND

Ovarian stimulation (OS) during assisted reproductive technology (ART) appears to be an independent factor influencing the risk of low birth weight (LBW). Previous studies identified the association between LBW and placenta deterioration, potentially resulting from disturbed genomic DNA methylation in oocytes caused by OS. However, the mechanisms by which OS leads to aberrant DNA methylation patterns in oocytes remains unclear.

METHODS

Mouse oocytes and mouse parthenogenetic embryonic stem cells (pESCs) were used to investigate the roles of OS in oocyte DNA methylation. Global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) levels were evaluated using immunofluorescence or colorimetry. Genome-wide DNA methylation was quantified using an Agilent SureSelectXT mouse Methyl-Seq. The DNA methylation status of mesoderm-specific transcript homologue (Mest) promoter region was analyzed using bisulfite sequencing polymerase chain reaction (BSP). The regulatory network between estrogen receptor alpha (ERα, ESR1) and DNA methylation status of Mest promoter region was further detected following the knockdown of ERα or ten-eleven translocation 2 (Tet2).

RESULTS

OS resulted in a significant decrease in global 5mC levels and an increase in global 5hmC levels in oocytes. Further investigation revealed that supraphysiological β-estradiol (E2) during OS induced a notable decrease in DNA 5mC and an increase in 5hmC in both oocytes and pESCs of mice, whereas inhibition of estrogen signaling abolished such induction. Moreover, Tet2 may be a direct transcriptional target gene of ERα, and through the ERα-TET2 axis, supraphysiological E2 resulted in the reduced global levels of DNA 5mC. Furthermore, we identified that MEST, a maternal imprinted gene essential for placental development, lost its imprinted methylation in parthenogenetic placentas originating from OS, and ERα and TET2 combined together to form a protein complex that may promote Mest demethylation.

CONCLUSIONS

In this study, a possible mechanism of loss of DNA methylation in oocyte caused by OS was revealed, which may help increase safety and reduce epigenetic abnormalities in ART procedures.

A systematic review of genome-wide analyses of methylation changes associated with assisted reproductive technologies in various tissues

IMPORTANCE

Because analytic technologies improve, increasing amounts of data on methylation differences between assisted reproductive technology (ART) and unassisted conceptions are available. However, various studies use different tissue types and different populations in their analyses, making data comparison and integration difficult.

OBJECTIVE

To compare and integrate data on genome-wide analyses of methylation differences due to ART, allowing exposure of overarching themes.

EVIDENCE REVIEW

All studies undertaking genome-wide analysis of human methylation differences due to ART or infertility in any tissue type across the lifespan were assessed for inclusion.

FINDINGS

Seventeen studies were identified that met the inclusion criteria. One study assessed trophectoderm biopsies, 2 first-trimester placenta, 1 first-trimester fetal tissue, 2 term placenta, 7 cord blood, 3 newborn dried blood spots, 1 childhood buccal smears, 1 childhood peripheral blood, and 2 adult peripheral blood. Eleven studies compared tissues from in vitro fertilization (IVF) conceptions with those of unassisted conceptions, 4 compared intracytoplasmic sperm injection with unassisted conceptions, 4 compared non-IVF fertility treatment (NIFT) with unassisted conceptions, 4 compared NIFT with IVF, and 5 compared an infertile population (conceiving via various methods) with an unassisted presumably fertile population. In studies assessing placental tissue, 1 gene with potential methylation changes due to IVF when compared with unassisted conceptions was identified by 2 studies. In blood, 11 potential genes with methylation changes due to IVF compared with unassisted conceptions were identified by 2 studies, 1 of which was identified by 3 studies. Three potentially affected genes were identified by 2 studies involving blood between intracytoplasmic sperm injection and unassisted populations. There were no overlapping genes identified in any tissue type between NIFT and unassisted populations, between NIFT and IVF, or the infertility combined population when compared with the unassisted fertile population.

CONCLUSIONS

Comparing studies is challenging due to differing variables between analyses. However, even in similar tissue types and populations, overlapping methylation changes are limited, suggesting that differences due to ART are minimal.

RELEVANCE

Information from this systematic review is significant for providers and patients who provide and use ART to understand methylation risks that may be associated with the technology.

Maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology in British Columbia

OBJECTIVE

To evaluate the odds of developing adverse maternal and perinatal outcomes in primiparous singleton pregnancies conceived with assisted reproductive technology (ART) compared with pregnancies conceived without ART.

STUDY DESIGN

A retrospective population-based cohort study using data from the British Columbia Perinatal Data Registry. The population included primiparous women with singleton live or stillbirths delivering at or after 20 weeks' gestation between April 1st 2008-March 31st, 2021. Women who conceived with ART were compared with those who conceived without ART. The main outcome measures were gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, neonatal intensive care unit admission, stillbirth, and 5-minute Apgar score. Adjusted odds ratios were calculated.

RESULTS

The study population included 191,059 primiparous women: 183,819 conceived without ART, 7,240 conceived using ART. After controlling for age, body mass index, pre-gestational diabetes, and smoking status, singleton pregnancies conceived by ART had significantly higher odds of gestational diabetes (OR 1.18, 95 % confidence interval [CI] 1.10-1.26) and hypertensive disorders of pregnancy (OR 1.39, 95 % CI 1.29-1.51). There were also significantly increased odds of preterm birth (OR 1.35, 95 % CI 1.25-1.46), low birth weight (OR 1.35, 95 % CI 1.23-1.49), and neonatal intensive care unit admission (OR 1.21, 95 % CI 1.11-1.32). There was not a statistically significant difference in the odds of stillbirth (OR 1.06, 95 % CI 0.72-1.57) or 5-minute Apgar score < 7 (OR 1.10, 95 % CI 0.97-1.26).

CONCLUSION

There is an increased odds of developing several adverse maternal or neonatal outcomes in primiparous singleton pregnancies conceived by ART including gestational diabetes, hypertensive disorders of pregnancy, preterm birth, low birth weight, and increased incidence of neonatal intensive care unit admissions.

Genetics in reproductive endocrinology and infertility

Tremendous advances in genetics have transformed the field of reproductive endocrinology and infertility over the last few decades. One of the most prominent advances is preimplantation genetic testing (PGT), which allows for the screening of embryos obtained during in vitro fertilization before transfer. Moreover, PGT can be performed for aneuploidy screening, detection of monogenic disorders, or exclusion of structural rearrangements. Refinement of biopsy techniques, such as obtaining samples at the blastocyst rather than the cleavage stage, has helped optimize results from PGT, and technological advances, including next-generation sequencing, have made PGT more efficient and accurate. The continued evolution of the approach to PGT has the potential to further enhance the accuracy of results, expand the application to other conditions, and increase access by reducing cost and improving efficiency.

Progesterone levels during ovarian stimulation in segmented ART cycles inversely correlate with normalized birthweight of neonates conceived through subsequent frozen-thawed embryo transfer

PURPOSE

To evaluate the association between serum progesterone (P) at the day of ovulation trigger and neonatal birthweight in singletons born after frozen-thawed embryo transfer in segmented ART cycles.

METHODS

A retrospective multicenter cohort study involving data from patients who achieved uncomplicated pregnancy and term delivery of ART-conceived singleton babies following a segmented GnRH antagonist cycle. The main outcome was birthweight's z-score of the neonate. Univariate and multivariate linear logistic regression analyses were made to investigate the relation of z-score with variables inherent to the patient and to the ovarian stimulation. The variable P per oocyte was created by dividing the value of progesterone at ovulation trigger by the number of oocytes retrieved at oocyte retrieval.

RESULTS

A total of 368 patients were included in the analysis. At univariate linear regression, the birthweight z-score of the neonate appeared to be inversely related to both P levels at the ovulation trigger (- 0.101, p = 0.015) and P levels per oocyte at trigger (- 1.417, p = 0.001), while it was directly related to the height of the mother (0.026, p = 0.002) and to the number of previous live births (0.291, p = 0.016). In multivariate analysis, both serum P (- 0.1; p = 0.015) and P per oocyte (- 1.347, p = 0.002) maintained the significant inverse association with birthweight z-score after adjusting for height and parity.

CONCLUSIONS

Serum progesterone level on the day of ovulation trigger inversely correlates with normalized birthweight of neonates in segmented GnRH antagonist ART cycles.

Long-Term Effects of ART on the Health of the Offspring

Assisted reproductive technologies (ART) significantly increase the chance of successful pregnancy and live birth in infertile couples. The different procedures for ART, including in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), intrauterine insemination (IUI), and gamete intrafallopian tube transfer (GIFT), are widely used to overcome infertility-related problems. In spite of its inarguable usefulness, concerns about the health consequences of ART-conceived babies have been raised. There are reports about the association of ART with birth defects and health complications, e.g., malignancies, high blood pressure, generalized vascular functional disorders, asthma and metabolic disorders in later life. It has been suggested that hormonal treatment of the mother, and the artificial environment during the manipulation of gametes and embryos may cause genomic and epigenetic alterations and subsequent complications in the health status of ART-conceived babies. In the current study, we aimed to review the possible long-term consequences of different ART procedures on the subsequent health status of ART-conceived offspring, considering the confounding factors that might account for/contribute to the long-term consequences.

The risk factors of procedure-related complications after amniocentesis in twin pregnancies: a retrospective analysis

BACKGROUND

There is an increasing demand for prenatal diagnostic testing in twin pregnancies, however, anecdotally there is a higher incidence of procedure-related complications after amniocentesis than that in singleton pregnancies. There is a paucity of data regarding risk factors of amniocentesis in twin pregnancies.

METHODS

Women with twin pregnancies who underwent amniocentesis between January 2016 and December 2020 were enrolled in this retrospective study. Procedure-related complications including spontaneous miscarriage, intrauterine fetal death, spontaneous preterm delivery, preterm premature rupture of membranes, and placental abruption in one or both fetuses after amniocentesis were assessed. Meanwhile, potential risk factors related to amniocentesis including chorionicity, gestational age, conception, number of needle insertions, parity, history of miscarriage, indications, and pregnancy-related complications (pregnancy-induced hypertension and gestational diabetes) were also recorded.

RESULTS

A total of 811 women with twin pregnancies underwent amniocentesis were included, with a procedure-related complications rate of 3.83%. Risk factors associated with increased risk of procedure-related complications after amniocentesis in twin pregnancies were chorionicity (adjusted odds ratio [aOR]: 4.06), gestational age at the procedure (aOR: 2.76), and numbers of needle insertions (aOR: 3.26). In the monochorionic twin pregnancy, hemorrhage during this pregnancy (aOR: 12.01), polyhydramnios (aOR: 5.03), and numbers of needle insertions (aOR: 3.15) were risk factors after amniocentesis. In the dichorionic twin pregnancy, gestational age at the procedure (OR:4.47) affected the risk of procedure-related complications after amniocentesis. In the subgroup of gestational age at the procedure ≤ 24+ 0 weeks, risk factors associated with increased risk of procedure-related complications after amniocentesis in twin pregnancies were chorionicity (aOR: 5.14), and numbers of needle insertions (aOR: 3.76).

CONCLUSION

The procedure-related complications rate is 3.83% in our institution during the study period. The present study has emphasized the significance of certain risk factors for adverse outcome and will be useful in counseling patients with twin pregnancies.

Assisted reproductive technology (ART) and epigenetic modifications in the placenta

Assisted reproductive technology (ART) has become common amongst couples with infertility issues. ART is known to be successful, but epidemiological data indicates that ART is associated with placental disorders. Additionally, reports show increased risks of short- and long-term complications in children born to mothers undergoing ART. However, the mechanisms responsible for these events are obscure. The placenta is considered as a key organ for programming of diseases and ART procedures are suggested to alter the placental function and intrauterine growth trajectories. Epigenetic changes in maternal and foetal tissues are suggested to be the underlying mechanisms for these outcomes. Epigenetic regulation is known to evolve following fertilisation and before implantation and subsequently across gestation. During these critical periods of epigenetic 'programming', DNA methylation and chromatin remodelling influence the placental structure and function by regulating the expression of various genes. ART treatment coinciding with epigenetic 'programming' events during gametogenesis and early embryo development may alter the programming phases leading to long-term consequences. Thus, disruptions in placental development observed in ART pregnancies could be associated with altered epigenetic regulation of vital genes in the placenta. The review summarises available literature on the influence of ART procedures on epigenetic changes in the placenta.

Plastic used in in vitro fertilization procedures induces massive placental gene expression alterations

BACKGROUND

The exposure to plastic derivatives during human life is deleterious. Infants conceived using ART (IVF or ICSI) have twice as many risks of major birth defects compared to naturally conceived infants. Could plastic ware used during ART trigger defects in the fetal development?

METHODS

Three groups of blastocysts were transferred to pseudopregnant mice. One was obtained after IVF and embryo development in plastic ware, the second in glass ware. The third, was obtained in vivo by natural mating. On day 16.5 of pregnancy, females were sacrificed and fetal organs collected for gene expression analysis. Fetal sex was determined by RT-PCR. RNA was extracted from a pool of five placental or brain samples coming from at least two litters from the same group and analyzed by hybridisation onto the mouse Affymetrix 430.2.0 GeneChips, confirmed by RT-qPCR for 22 genes.

FINDINGS

This study highlights a major impact of plastic ware on placental gene expression (1121 significantly deregulated genes), while glassware was much closer to in vivo offspring (only 200 significantly deregulated genes). Gene Ontology indicated that the modified placental genes were mostly involved in stress, inflammation and detoxification. A sex specific analysis revealed in addition a more drastic effect on female than male placentas. In the brains, whatever the comparison, less than 50 genes were found deregulated.

INTERPRETATION

Embryos incubated in plastic ware resulted in pregnancy with massive alterations of placental gene expression profile in concerted biological functions. There were no obvious effects on the brains. Besides other effects, this suggests that plastic ware in ART could be a cause of the increased level of pregnancy disorders observed recurrently in ART pregnancies.

FUNDING

This study was funded by two grants from the Agence de la Biomedecine in 2017 and 2019.

Placental perfusion using intravoxel incoherent motion MRI combined with Doppler findings in differentiating between very low birth weight infants and small for gestational age infants

INTRODUCTION

Abnormalities in placental morphology and function can lead to small for gestational age infants (SGA) and very low birth weight infants (VLBWI). In this study, we explored the value of intravoxel incoherent motion (IVIM) histogram parameters, MRI morphological parameters, and Doppler findings of the placenta in differentiating between VLBWI and SGA.

METHODS

Thirty-three pregnant women who were diagnosed with SGA and met the inclusion criteria were enrolled in this retrospective study and divided into two groups: 22 with non-VLBWI and 11 with VLBWI. The IVIM histogram parameters (perfusion fraction (f), true diffusion coefficient (D), and pseudo-diffusion coefficient (D*)), MRI morphological parameters, and Doppler findings were compared between groups. The diagnostic efficiency was compared by receiver operating characteristic (ROC) curve analysis.

RESULTS

The D_mean, D_90th, D*_90th, f_max, and placental area of the VLBWI group were significantly lower than those of the non-VLBWI group (p < 0.05). The values of umbilical artery pulsatility index, resistance index (RI), and peak systolic velocity/end-diastolic velocity were significantly higher in the VLBWI group than in the non-VLBWI group (p < 0.05). D_90th, placental area, and umbilical artery RI had the highest areas under the curve (AUCs) of the ROC curves, at 0.787, 0.785, and 0.762, respectively. A combined predictive model (D_90th, placental area, and umbilical artery RI) improved the performance in differentiating between VLBWI and SGA compared with the single model (AUC = 0.942).

DISCUSSION

IVIM histogram (D_90th) and MRI morphological (placental area) parameters and a Doppler finding (umbilical artery RI) may be sensitive indicators for differentiating between VLBWI and SGA.

Infertility and treatments used have minimal effects on first-trimester placental DNA methylation and gene expression

OBJECTIVE

To determine whether deoxyribonucleic acid (DNA) methylation alterations exist in the first-trimester human placenta between conceptions using fertility treatments and those that do not and, if so, whether they are the result of underlying infertility or fertility treatments. We also assessed whether significant alterations led to changes in gene expression.

DESIGN

We compared DNA methylation of the first-trimester placenta from singleton pregnancies that resulted in live births from unassisted, in vitro fertilization (IVF), and non-IVF fertility treatment (NIFT) conceptions using the Infinium MethylationEPIC BeadChip array. Significant CpG sites were compared with corresponding ribonucleic acid sequencing analysis in similar cohorts to determine whether methylation alterations lead to differences in gene expression.

SETTING

Academic medical center.

PATIENT(S)

A total of 138 singleton pregnancies undergoing chorionic villus sampling resulting in a live birth were recruited for methylation analysis (56 unassisted, 38 NIFT, and 44 IVF conceptions). Ribonucleic acid-sequencing data consisted of 141 subjects (74 unassisted, 33 NIFT, and 34 IVF conceptions) of which 116 overlapped with the methylation cohort.

INTERVENTION(S)

In vitro fertilization-conceived pregnancy or pregnancy conceived via NIFT, such as ovulation induction and intrauterine insemination.

MAIN OUTCOME MEASURE(S)

Significant methylation changes at CpG sites after adjustment for multiple comparisons. The secondary outcome was gene expression changes of significant CpG sites.

RESULT(S)

Of the 741,145 probes analyzed in the placenta, few were significant at Bonferroni <0.05: 185 CpG sites (0.025%) significant in pregnancies conceived with the fertility treatments (NIFT + IVF) vs. unassisted conceptions; 28 in NIFT vs. unassisted; 195 in IVF vs. unassisted; and only 13 (0.0018%) in IVF vs. NIFT conceptions. Of all significant CpG sites combined, 10% (35) were located in genes with suggestive gene expression changes, but none were significant after adjustment for multiple comparisons (ribonucleic acid sequencing false discovery rate <0.05). None of the 13 differentially methylated probes in the IVF vs. NIFT placenta were located in genes with suggestive IVF vs. NIFT gene expression differences.

CONCLUSION(S)

Underlying infertility is the most significant contributor to the minimal differences in first-trimester placental methylation, and not the specific fertility treatment used, such as IVF.

Association of maternity formula supplementation during pregnancy with small for gestational age birth in Chinese newborns

OBJECTIVES

This study aimed to explore the association between maternity formula supplementation and small for gestational age (SGA) status in Chinese newborns.

METHODS

Data were from a population-based cross-sectional survey conducted in Shaanxi, Northwest China between August and December 2013. A total of 27 780 women pregnant with singletons and 356 with twins were included in this survey. Information on use of maternity formulas fortified with vitamins, folic acid, pantothenic acid, calcium, iron, zinc, and docosahexaenoic acid (DHA) was collected. SGA was defined as birthweight <10th percentile of fetal growth. Generalized linear models and estimating equation models were used to estimate crude odds ratios (ORs) or adjusted ORs with 95% confidence intervals (CIs) for SGA.

RESULTS

The rate of maternity formula supplementation during the entire pregnancy was 13.0% in the overall population. There was no significant association between maternal formula supplementation during pregnancy and the risk of total SGA birth (OR: 1.00; 95% CI, 0.90-1.11; P = 0.950). However, maternity formula supplementation during pregnancy was related to a lower risk of SGA for twins (OR: 0.49; 95% CI, 0.31-0.80; P = 0.004), twin A (OR: 0.50; 95% CI, 0.25-0.98; P = 0.045), and twin B (OR: 0.48; 95% CI, 0.25-0.95; P = 0.034). Furthermore, maternity formula supplementation during the first trimester was inversely associated with the risk of SGA birth of twins (OR: 0.32; 95% CI, 0.15-0.65; P = 0.002).

CONCLUSIONS

No significant association was observed between maternity formula supplementation and total SGA birth. However, women supplemented with maternal formula during pregnancy, especially during the first trimester, may have a reduced risk of SGA birth of twins.

Trends and characteristics of multiple births in Baoan Shenzhen: A retrospective study over a decade

Background

Shenzhen has the largest and youngest foreign population among all cities in China. The reproductive health of pregnant women from different backgrounds is a social issue that deserves attention. In the past decade, China has liberalized its population policies to stimulate population growth, and the proportion of multiple births has continued to increase.

Method

This retrospective cohort included 526,654 newborns born in Baoan, Shenzhen, from January 1, 2009, to December 31, 2019, including 515,016 singletons and 11,638 twins or triplets. Univariate regression models were used to analyze the effects of maternal sociodemographic characteristics, physiological characteristics, medical history, antenatal care and other factors associated with single vs. multiple births and to elucidate the changing trends of different factors affecting multiple births in the past 11 years. Additionally, fetal development in multiple births was analyzed by generalized linear mixed models.

Results

The rates of pregnancy complications, preterm birth, and advanced-age pregnancy were significantly higher in the multiple birth mothers than in single birth mothers, and more multiple pregnancies were achieved through assisted reproductive technologies. The rates of adverse outcomes such as stillbirth, malformation, hypoxia, and ultralow body weight in multiple fetuses were significantly higher than that in singleton fetuses. The trend analysis from 2009 to 2019 showed that the socioeconomic status and health level of mothers with multiple births improved over time, and the risk during pregnancy generally decreased. Simultaneously, the development indicators of multiple fetuses have improved year by year, and the proportion of adverse outcomes has also decreased significantly. A low pre-natal care utilization rate was shown to be detrimental to the development of multiple fetuses. Independent risk factors for hypoxia and very low birth weight were also identified. The differences in secular trends between two birth groups were further revealed by time series models.

Conclusion

This study presented a comprehensive survey of multiple pregnancies in the area with the largest population inflow in China. This study identified the factors that affect the health of multiple birth mothers and their fetuses, particularly suggesting that preterm birth rates and the use of assisted reproduction remain high. The findings provide a basis for the formulation of individualized pre-natal care, assisted reproductive guidance and healthcare policies for multiple births.

The longer-term effects of IVF on offspring from childhood to adolescence

It is well established that there are increased pregnancy-related complications for a woman who conceives through assisted reproductive treatment (ART). Furthermore, it is known that the risk to the child born is greater, believed to be related to prematurity and growth restriction. Studies have also reported epigenetic changes in the DNA of offspring conceived through ART. In addition, it is believed that they have a greater risk of congenital malformations, although some of these risks may relate to underlying infertility, rather than the ART treatment per se. As a result, it may be expected that there is a greater risk to the longer-term health of the child who is born from ART; however, evidence about the long-term health of children conceived through ART is reassuring. Even though, it is recognised that many of the studies in this field come with limitations. Low numbers of participants is one of the major limitations, which makes subgroup analyses for diverse types of ART, or diverse types of infertility, not feasible. Furthermore, studies are often limited by short follow-up periods because of the difficulty and costs involved in longitudinal study designs. In addition, the rapid changes over time in ART limit the generalisability and significance of long-term findings. Well-designed studies investigating the long-term health outcomes of ART-conceived offspring and the potential influences of various aspects of the ART procedure, as well as studies of the potential underlying epigenetic mechanisms, are imperative. Furthermore, conclusions from childhood hospitalisation data from the United Kingdom, the long-term follow-up and quality of life study from researchers in Melbourne, and the data published from the Western Australian Growing Up Healthy Study will go a long way to help reassure current and prospective parents who may require ART to conceive.

Effects of External Radiation Exposure on Perinatal Outcomes in Pregnant Women After the Fukushima Daiichi Nuclear Power Plant Accident: the Fukushima Health Management Survey

BACKGROUND

This study aimed to investigate the effects of maternal exposure to external radiation on perinatal outcomes among women who experienced the Fukushima Daiichi Nuclear Disaster (FDND) using the Fukushima Health Management Survey (FHMS).

METHODS

Data from the Pregnancy and Birth Survey and Basic Survey in the FHMS were combined to analyze external maternal radiation exposure following the FDND, and the relationship between radiation dose and perinatal outcomes was analyzed using binomial logistic regression analysis. Missing dose data were supplemented using multiple imputation.

RESULTS

A total of 6,875 individuals responded to the survey. Congenital anomalies occurred in 2.9% of patients, low birth weight (LBW) in 7.6%, small for gestation age (SGA; <10th percentile) in 8.9%, and preterm birth in 4.1%. The median maternal external radiation dose was 0.5 mSv (maximum, 5.2 mSv). Doses were classified as follows: <1 mSv (reference), 1 to <2 mSv, and ≥2 mSv. For congenital anomalies, the crude odds ratio for 1 to <2 mSv was 0.81 (95% confidence interval [CI], 0.56-1.17) (no participants with congenital anomaly were exposed to ≥2 mSv). At 1 to <2 mSv and ≥2 mSv, the respective adjusted odds ratios were 0.91 (95% CI, 0.71-1.18) and 1.21 (95% CI, 0.53-2.79) for LBW, 1.14 (95% CI, 0.92-1.42) and 0.84 (95% CI, 0.30-2.37) for SGA, and 0.91 (95% CI, 0.65-1.29) and 1.05 (95% CI, 0.22-4.87) for preterm birth.

CONCLUSION

External radiation dose due to the FDND was not associated with congenital anomalies, LBW, SGA, or preterm birth.

Mental health and behavioural problems in adolescents conceived after ART

STUDY QUESTION

Does mental health and behaviour differ between those conceived with and those conceived without ART?

SUMMARY ANSWER

Our study observed less externalizing behaviour (delinquent/aggressive), and more parent-reported internalizing behaviour, as well as more (clinical) depression at age 14 years, in adolescents conceived after ART compared to their non-ART counterparts.

WHAT IS KNOWN ALREADY

Health outcomes of ART-conceived offspring may differ from those conceived without ART, and previous studies have reported differences in behaviour and mental health, particularly in childhood.

STUDY DESIGN, SIZE, DURATION

The Growing Up Healthy Study (GUHS) is a prospective cohort study, investigating the long-term health of offspring conceived after ART (aged 14, 17 and 20 years), in the two operational fertility clinics in Western Australia 1991-2001 (n = 303). Their long-term health outcomes were compared to those of offspring conceived without ART from the Raine Study Generation 2 (Gen2) born 1989-1991 (n = 2868). Both cohorts are representative of the local adolescent population.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Mental health parameters and behaviour were assessed at ages 14 and 17 years, through the parent completed 'Child Behaviour Checklist' (CBCL; ART versus non-ART: age 14 years: N = 150 versus N = 1781, age 17 years: N = 160 versus N = 1351), and the adolescent completed equivalent 'Youth Self-Report' (YSR; age 14 years: by N = 151 versus N = 1557, age 17 years: N = 161 and N = 1232). Both tools generate a T-score (standardized for age and sex) for internalizing (withdrawn, somatic complaints, anxious/depressed), externalizing (delinquent/aggressive behaviour) and total behaviour. Adolescents also completed the 'Beck Depression Inventory for Youth' (BDI-Y; age 14 years: N = 151 versus N = 1563, age 17 years: N = 161 versus N = 1219). Higher scores indicate poorer mental health and behaviour on all the above tools. Parent-reported doctor-diagnosed conditions (anxiety, behavioural problems, attention problems and depression) were also univariately compared between the cohorts. In addition, univariate comparisons were conducted between the GUHS adolescents and Gen2 adolescents born to subfertile parents (time to pregnancy >12 months), as well as between offspring born to subfertile versus fertile parents within the Gen2 cohort. A subgroup analysis excluding offspring born preterm (<37 weeks' gestation) or at low birthweight (<2500 g) was also performed. Generalized estimating equations that account for correlated familial data were adjusted for the following covariates: non-singleton, primiparity, primary caregiver smoking, family financial problems, socio-economic status and both maternal and paternal ages at conception.

MAIN RESULTS AND THE ROLE OF CHANCE

At both 14 and 17 years of age, ART versus non-ART-conceived adolescents reported lower mean T-scores for externalizing problems (age 14 years: 49 versus 51, P = 0.045, age 17 years: 49 versus 52, P < 0.001). A similar effect was reported by parents, although not significant (age 14 years: P = 0.293, age 17 years: P = 0.148). Fewer ART-conceived adolescents reported a T-score above the clinical cut-off for externalizing behaviour (≥60; age 14 years: 7.3% versus 16.3%, P = 0.003, age 17 years: 8.1% versus 19.7%, P < 0.001). At both ages, no differences in internalizing behaviour were reported by adolescents (age 14 years: P = 0.218, age 17 years: P = 0.717); however, higher mean scores were reported by parents of the ART-conceived adolescents than by parents of the non-ART conceived adolescents (age 14 years: 51 versus 48, P = 0.027, age 17 years: 50 versus 46, P < 0.001). No differences in internalizing behaviour above the clinical cut-off (T-score ≥ 60) were observed. At age 17 years, parents who conceived through ART reported higher total behaviour scores than those parents who conceived without ART (48 versus 45, P = 0.002). At age 14 years, ART versus non-ART-conceived adolescents reported significantly higher mean scores on the BDI-Y (9 versus 6, P = 0.005); a higher percentage of adolescents with a score indicating clinical depression (≥17; 12.6% versus 8.5%, aOR 2.37 (1.18-4.77), P = 0.016), as well as more moderate/severe depression (≥21; 9.3% versus 4.0%, P = 0.009). At age 17 years, no differences were reported on the BDI-Y. There was also a higher percentage of parent-reported doctor-diagnosed anxiety in the ART cohort (age 14 years: 8.6% versus 3.5%, P = 0.002, at age 17 years: 12.0% versus 4.5%, P < 0.001). Removing adolescents born preterm or at low birthweight did not alter the above results. Comparing outcomes between GUHS adolescents and Gen2 adolescents born to subfertile parents, as well as between those born to subfertile versus fertile parents within Gen2, did not alter results for CBCL and YSR outcomes. Those born to subfertile parents showed higher rates of clinical depression than those born to fertile parents at age 14 years (13.7% versus 6.9%, P = 0.035).

LIMITATIONS, REASONS FOR CAUTION

The main limitation of the study is the time difference between the GUHS and Gen2 assessments. Even though we have adjusted for covariates, additional socio-economic and lifestyle factors affecting behaviour and mental well-being could have changed. We were unable to differentiate between different types of ART (e.g. IVF versus ICSI), owing to the low number of ICSI cycles at the time of study. Fertility sub-analyses need to be replicated in larger cohorts to increase power, potentially using siblingship designs. Lastly, selection bias may be present.

WIDER IMPLICATIONS OF THE FINDINGS

The reported lower prevalence of externalizing behaviour (delinquent/aggressive), and higher prevalence of internalizing behaviour, as well as more (clinical) depression at age 14 years, in ART versus non-ART-conceived adolescents, is in line with some previous studies, mostly conducted in childhood. It is reassuring that differences in the rates of depression were not observed at age 17 years, however, these findings require replication. As the use of ART is common, and mental health disorders are increasing, knowledge about a potential association is important for parents and healthcare providers alike.

STUDY FUNDING/COMPETING INTEREST(S)

This project was funded by an NHMRC Grant (Hart et al., ID 1042269). R.J.H. is the Medical Director of Fertility Specialists of Western Australia and a shareholder in Western IVF. He has received educational sponsorship from MSD, Merck-Serono and Ferring Pharmaceuticals. P.B. is the Scientific Director of Concept Fertility Centre, Subiaco, Western Australia. J.L.Y. is the Medical Director of PIVET Medical Centre, Perth, Western Australia.

TRIAL REGISTRATION NUMBER

N/A.

E2 level > 2950 pg/ml on hCG trigger day is an independent predictor for birthweight loss of full-term singletons born after fresh embryo transfers in non-PCOS patients

BACKGROUND

Previous studies have demonstrated that the supraphysiological E2 level is negatively correlated with birthweight. However, the cut-off value of E2 level that significantly affects birthweight is unknown, and there is no definite conclusion regarding this level. Our study aimed to explore the threshold of the effect of E2 levels on birthweight.

DESIGN

A retrospective cohort study of 1846 samples was performed. All patients ≤42-years-old underwent autologous IVF cycles between August 1st, 2016 and April 30th, 2020. We categorized our data into four groups according to the E2 level: Group 1: ≤2000 pg/mL; Group 2: 2001-3000 pg/mL; Group 3: 3001-4000 pg/mL; and Group 4: > 4000 pg/mL.

RESULTS

The results of the multivariate regression analyses showed that when the E2 level was 3001-4000 pg/mL (adjusted β: - 89.64, 95% [CI]: - 180.29 to - 6.01; P = 0.0336) and greater than 4000 pg/mL (adjusted β: - 138.10, 95% [CI]: - 272.87 to - 10.33; P = 0.0181), weight loss was significant. Furthermore, the odds of full-term SGA were 1.40 times higher with E2 levels of 3001-4000 pg/mL (adjusted OR: 1.40, 95% [CI]: 1.090 to 3.18; P = 0.0256) and 2.55 times higher with E2 > 4000 pg/mL (adjusted OR: 2.55, 95% [CI]: 1.84 to 3.86; P = 0.0063) compared to the reference group. It can also be seen from the adjusted curves and the threshold effects that when the E2 level > 2950 pg/mL and > 3121 pg/mL, the incidence of SGA increased and the birthweight decreased, respectively.

CONCLUSIONS

Our data suggest that E2 levels > 2950 pg/mL is an independent predictor for greater odds of full-term SGA singletons born after fresh embryo transfer.

Disrupted methylation patterns at birth persist in early childhood: a prospective cohort analysis

BACKGROUND

Alterations in the epigenome are a risk factor in multiple disease states. We have demonstrated in the past that disruption of the epigenome during early pregnancy or periconception, as demonstrated by altered methylation, may be associated with both assisted reproductive technology and undesirable clinical outcomes at birth, such as low birth weight. We have previously defined this altered methylation, calculated based on statistical upper and lower limits of outlier CpGs compared to the population, as an 'outlier methylation phenotype' (OMP). Our aim in this study was to determine whether children thus identified as possessing an OMP at birth by DNA methylation in cord blood persist as outliers in early childhood based on salivary DNA methylation.

RESULTS

A total of 31 children were included in the analysis. Among 24 children for whom both cord blood DNA and salivary DNA were available, DNA methylation patterns, analyzed using the Illumina Infinium MethylationEPIC BeadChip (850 K), between cord blood at birth and saliva in childhood at age 6-12 years remain stable (R2 range 0.89-0.97). At birth, three out of 28 children demonstrated an OMP in multiple cord blood datasets and hierarchical clustering. Overall DNA methylation among all three OMP children identified as outliers at birth was remarkably stable (individual R2 0.908, 0.92, 0.915), even when only outlier CpG sites were considered (R2 0.694, 0.738, 0.828).

CONCLUSIONS

DNA methylation signatures in cord blood remain stable over time as demonstrated by a strong correlation with epigenetic salivary signatures in childhood. Future work is planned to identify whether a clinical phenotype is associated with OMP and, if so, could undesirable clinical outcomes in childhood and adulthood be predicted at birth.

Altered Expression of Pulmonary Epithelial Cell Markers in Fetal and Adult Mice Generated by in vitro Embryo Culture and Embryo Transfer

Lung development is impaired in mice generated through transfer of in vitro-derived blastocysts. The main objective of the current study was to determine if the composition of epithelial cells in the fetal and adult lung tissue is altered in mice generated through transfer of in vitro-derived blastocysts. The study comprised two experimental (EGs) and two control (CGs) groups. Fetuses (18.5 d.p.c.) and adult mice (8 weeks old) of the EGs (EGfetus, n = 18; EGadult, n = 15) were produced by the transfer of day 5 F2 blastocysts to pseudo-pregnant females. F2 fetuses and adult mice derived from naturally ovulating females served as the CGs (CGfetus, n = 18; CGadult, n = 15). The expression of Tuba-1a (a marker of ciliated cells), Foxj-1 (a marker of motile ciliated cells), Uch-L1 (a marker of neuroendocrine cells), Cldn-10 (a marker of club cells), Aqp-5 (a marker of type I alveolar cells), and Sp-C (a marker of type II alveolar cells) was determined using Western blot, immunohistochemistry/immunofluorescence, and quantitative RT-PCR analyses. Weight of fetuses as well as adult mice is decreased in mice comprising the EGs. Impaired lung development observed in EGfetus was associated with altered expression of Tuba-1a, Foxj-1, Cldn-10, Uch-L1, Sp-C, and Aqp-5. Morphology of the adult lung tissue was similar between the groups except for a significant increase in the thickness of the epithelia in EGadult. The expression of Cldn-10 and Sp-C was also altered in EGadult. It remains to be determined whether altered expression of these genes has any long-term impact on epithelial cell functions in the adult lung tissue.

Clinical implications of first-trimester ultrasound dating in singleton pregnancies obtained through in vitro fertilization

Background

In pregnancies obtained by in-vitro fertilization (IVF) the exact day of conception is known. For that reason, IVF pregnancies are currently dated according to the day of oocytes retrieval and consequent embryo transfer. The aim of the present study is to determine whether the knowledge of the exact day of conception in IVF pregnancies is a sufficient argument against dating these pregnancies by first trimester ultrasound measurement of the crown-rump length (CRL), as it is recommended in natural conceptions.

Methods

A retrospective study was performed, including all women with singleton pregnancies conceived by IVF who underwent the first-trimester ultrasound scan for the screening of aneuploidies between January 2014 and June 2019. For each pregnancy GA was determined using two alternative methods: one based on the date of embryo transfer (GA_IVF), and one based on ultrasound measurement of CRL (GA_US). GA were compared to search for any discrepancy. The impact of pregnancy dating on obstetric outcome was evaluated.

Results

Overall, 249 women were included. Comparing GA_US and GA_IVF, a median difference of 1 [0 – 2] days emerged (p<0.001), with GA_US being in advance compared to GA_IVF. This discrepancy persisted when subgroups were analyzed comparing different IVF procedures (conventional IVF versus ICSI, cleavage versus blastocyst transfer, frozen versus fresh transfer). No impact of the dating method on obstetric outcomes was observed, being no differences in the rate of preterm birth or abnormal fetal growth.

Conclusions

In IVF pregnancies GA_US and GA_IVF are not overlapping, since GA_US is mildly greater than GA_IVF. This could be due to an anticipated ovulation and fertilization in IVF pregnancy, rather than an accelerated embryo development. For that reason, it would be appropriate to date IVF pregnancies according to GA_US, despite a known date of conception, to re-align IVF pregnancies to natural ones.

Maternal Folic Acid Supplementation, Dietary Folate Intake, and Low Birth Weight: A Birth Cohort Study

Objectives

To investigate the independent and collective effects of maternal folic acid supplementation or dietary folate intake on the risk of low birth weight (LBW), and to further comprehensively examine the joint associations of folic acid supplementation and dietary folate intake with LBW by various clinical subtypes.

Design

Participants were recruited from Gansu Provincial Maternity and Child Care Hospital. A standardized and structured questionnaire was distributed to collect demographic factors, reproductive and medical history, occupational and residential history, physical activity, and diet. Data on pregnancy-related complications and birth outcomes were extracted from medical records. Unconditional logistic regression models were used to estimate the odds ratio (OR) and 95% confidence interval (95% CI) for single and joint associations of folic acid supplementation and dietary folate intake with LBW.

Setting

A birth cohort data analysis using the 2010–2012 Gansu Provincial Maternity and Child Care Hospital in Lanzhou, China.

Participants

In total, 9,231 pregnant women and their children were enrolled in the study.

Results

Compared with non-users, folic acid supplementation was associated with a reduced risk of LBW (OR: 0.80, 95% CI: 0.66–0.97), and the reduced risk was mainly seen for term-LBW (OR: 0.59, 95% CI: 0.41–0.85), and multiparous-LBW (OR: 0.72, 95% CI: 0.54–0.94). There were no significant associations between dietary folate intake and LBW, and there was no interaction between folic acid supplement and dietary folate intake on LBW.

Conclusions

Our study results indicated that folic acid supplementation was associated with a reduced risk of LBW, and there was no interaction between folic acid supplements and dietary folate intake on LBW.

Analysis of the risk of complications during pregnancy in pregnant women with assisted reproductive technology: a retrospective study using registry linkage from 2013 to 2018 in Shanghai, China

Background

To evaluate the differences in pregnancy outcomes between assisted reproductive technology (ART) patients and natural pregnant women in Shanghai, China in the past 6 years objectively. And to assess the feasibility of the research method of registry-database linkage in mainland China.

Methods

This retrospective study was conducted using registry-database linkage. A total of 8102 pregnancies with ART and 8096 parturients with spontaneous conception (SC) from 10 reproductive centers and 111 hospitals composed our retrospective study. The primary outcomes were the rates of obstetric complications (pregnancy-induced hypertention [PIH], gestational diabetes mellitus [GDM], placenta previa, mode of delivery, preterm birth [PTB], low birth weight [LBW], and macrosomia). The prenatal outcomes were compared between ART and SC parturients, frozen-thawed embryo transfer (FET) and fresh embryo transfer, and in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). We calculated odds ratios (ORs) and 95% confidence intervals (CIs).

Results

The final matching rate of the target population was 92% by using registry linkage. ART resulted in a higher rate of multiple birth, PTB, LBW, cesarean section, placenta previa and GDM compared with SC in the singleton cohort. In ART patients, pregnant women with FET had a significantly higher risk of PIH than those with fresh embryo transfer (14.1% Vs 9.3%, AOR1.528, 95% CI 1.303–1.793), but there was no difference between IVF and ICSI. FET is also related to the severity of PIH.

Conclusions

ART increased the rate of complications during pregnancy, the risk and severity of PIH in patients with FET was higher than that in patients with fresh embryo transfer. The registry-database linkage study is an objective and feasible research method in mainland China.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04846-1.

Infertility in Men: Advances towards a Comprehensive and Integrative Strategy for Precision Theranostics

Male infertility is an increasing and serious medical concern, though the mechanism remains poorly understood. Impaired male reproductive function affects approximately half of infertile couples worldwide. Multiple factors related to the environment, genetics, age, and comorbidities have been associated with impaired sperm function. Present-day clinicians rely primarily on standard semen analysis to diagnose male reproductive potential and develop treatment strategies. To address sperm quality assessment bias and enhance analysis accuracy, the World Health Organization (WHO) has recommended standardized sperm testing; however, conventional diagnostic and therapeutic options for male infertility, including physical examination and semen standard analysis, remain ineffective in relieving the associated social burden. Instead, assisted reproductive techniques are becoming the primary therapeutic approach. In the post-genomic era, multiomics technologies that deeply interrogate the genome, transcriptome, proteome, and/or the epigenome, even at single-cell level, besides the breakthroughs in robotic surgery, stem cell therapy, and big data, offer promises towards solving semen quality deterioration and male factor infertility. This review highlights the complex etiology of male infertility, especially the roles of lifestyle and environmental factors, and discusses advanced technologies/methodologies used in characterizing its pathophysiology. A comprehensive combination of these innovative approaches in a global and multi-centric setting and fulfilling the suitable ethical consent could ensure optimal reproductive and developmental outcomes. These combinatorial approaches should allow for the development of diagnostic markers, molecular stratification classes, and personalized treatment strategies. Since lifestyle choices and environmental factors influence male fertility, their integration in any comprehensive approach is required for safe, proactive, cost-effective, and noninvasive precision male infertility theranostics that are affordable, accessible, and facilitate couples realizing their procreation dream.

Sex differences in the intergenerational inheritance of metabolic traits

Strong evidence suggests that early-life exposures to suboptimal environmental factors, including those in utero, influence our long-term metabolic health. This has been termed developmental programming. Mounting evidence suggests that the growth and metabolism of male and female fetuses differ. Therefore, sexual dimorphism in response to pre-conception or early-life exposures could contribute to known sex differences in susceptibility to poor metabolic health in adulthood. However, until recently, many studies, especially those in animal models, focused on a single sex, or, often in the case of studies performed during intrauterine development, did not report the sex of the animal at all. In this review, we (a) summarize the evidence that male and females respond differently to a suboptimal pre-conceptional or in utero environment, (b) explore the potential biological mechanisms that underlie these differences and (c) review the consequences of these differences for long-term metabolic health, including that of subsequent generations.

Maternal and Neonatal Outcomes After Assisted Reproductive Technology: A Retrospective Cohort Study in China

Background

With the progress of assisted reproductive technology (ART) and the increasing number of ART pregnancy, its safety has become the focus of attention. The present study aimed to explore the associations of ART pregnancy with maternal and neonatal outcomes, as compared with naturally pregnancy.

Methods

This retrospective cohort study included all pregnant women who delivered at Women’s Hospital of Nanjing Medical University in 2011–2020. We compared maternal characteristics and pregnancy outcomes between group of ART pregnancy and group of naturally pregnancy using Logistic regression adjusted for confounders.

Results

A total of 13,604 ART pregnancies and 198,002 naturally pregnancies were included. The proportion of ART pregnancies has increased every year for the past 10 years, peaking in 2020 (9.0%). Multivariable logistic regression analysis showed that the risks of gestational diabetes, preeclampsia, moderate or severe anemia, liver-related diseases, thyroid-related diseases, preterm birth, placenta previa, postpartum hemorrhage, and cesarean section were significantly increased in ART pregnancy. For neonatal outcomes, women conceived by ART were more likely to have twins or multiples, and the risk of stillbirth or abnormal development was also significantly increased. When restriction to singletons, these risks were reduced. And the effects of ART on the risk of premature rupture of membrane, cord entanglement, intrapartum fever, cesarean section, and stillbirth or abnormal development were more pronounced in singletons pregnancies compared with that in pregnancies of twins or multiples.

Conclusion

Women conceived by ART were at increased risks of several adverse pregnancy outcomes compared with women conceived naturally. Multiple pregnancies could partly explain this phenomenon. For ART pregnancy, prenatal and intrapartum monitoring should be strengthened, and neonatal outcomes should be closely observed.

Epigenetic Risks of Medically Assisted Reproduction

Since the birth of Louise Joy Brown, the first baby conceived via in vitro fertilization, more than 9 million children have been born worldwide using assisted reproductive technologies (ART). In vivo fertilization takes place in the maternal oviduct, where the unique physiological conditions guarantee the healthy development of the embryo. During early embryogenesis, a major wave of epigenetic reprogramming takes place that is crucial for the correct development of the embryo. Epigenetic reprogramming is susceptible to environmental changes and non-physiological conditions such as those applied during in vitro culture, including shift in pH and temperature, oxygen tension, controlled ovarian stimulation, intracytoplasmic sperm injection, as well as preimplantation embryo manipulations for genetic testing. In the last decade, concerns were raised of a possible link between ART and increased incidence of imprinting disorders, as well as epigenetic alterations in the germ cells of infertile parents that are transmitted to the offspring following ART. The aim of this review was to present evidence from the literature regarding epigenetic errors linked to assisted reproduction treatments and their consequences on the conceived children. Furthermore, we provide an overview of disease risk associated with epigenetic or imprinting alterations in children born via ART.

Fertility treatments and the risk of preterm birth among women with subfertility: a linked-data retrospective cohort study

Background

In vitro fertilization (IVF) births contribute to a considerable proportion of preterm birth (PTB) each year. However, there is no formal surveillance of adverse perinatal outcomes for less invasive fertility treatments. The study objective was to describe associations between fertility treatment (in vitro fertilization, intrauterine insemination, usually with ovulation drugs (IUI), or ovulation drugs alone) and preterm birth, compared to no treatment in subfertile women.

Methods

The Fertility Experiences Study (FES) is a retrospective cohort study conducted at the University of Utah between April 2010 and September 2012. Women with a history of primary subfertility self-reported treatment data via survey and interviews. Participant data were linked to birth certificates and fetal death records to asses for perinatal outcomes, particularly preterm birth.

Results

A total 487 birth certificates and 3 fetal death records were linked as first births for study participants who completed questionnaires. Among linked births, 19% had a PTB. After adjustment for maternal age, paternal age, maternal education, annual income, religious affiliation, female or male fertility diagnosis, and duration of subfertility, the odds ratios and 95% confidence intervals (CI) for PTB were 2.17 (CI 0.99, 4.75) for births conceived using ovulation drugs, 3.17 (CI 1.4, 7.19) for neonates conceived using IUI and 4.24 (CI 2.05, 8.77) for neonates conceived by IVF, compared to women with subfertility who used no treatment during the month of conception. A reported diagnosis of female factor infertility increased the adjusted odds of having a PTB 2.99 (CI 1.5, 5.97). Duration of pregnancy attempt was not independently associated with PTB. In restricting analyses to singleton gestation, odds ratios were not significant for any type of treatment.

Conclusion

IVF, IUI, and ovulation drugs were all associated with a higher incidence of preterm birth and low birth weight, predominantly related to multiple gestation births.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12978-022-01363-4.

Infertility treatments such as in vitro fertilization are associated with preterm birth, but less is known about how other less invasive treatments contribute to preterm birth. This study compares different types of fertility treatments and rates of preterm birth with women who are also struggling with infertility but did not use fertility treatments at the time of their pregnancy. 490 women were recruited at the University of Utah between 2010 and 2012. Participants were asked to complete a survey and were linked to birth certificate and fetal death certificate data. Women who used in vitro fertilization were 4.24 times more likely to have a preterm birth than those who used no treatment. Use of intrauterine insemination were 3.17 times more likely to have a preterm birth than those who used no treatment at time of conception. Ovulation stimulating drugs were 2.17 times more likely to have a preterm birth. Having female factor infertility was also associated with higher odds of having preterm birth. For those who are having trouble conceiving, trying less invasive treatments to achieve pregnancy might reduce their risk of preterm birth.

Racial/ethnic disparities in infertility treatment utilization in the US, 2011-2019

With delayed child-bearing age, there has been an increase in infertility rates globally and in the United States (US). Unsurprisingly, there has been a concomitant substantial increase in the number of individuals seeking infertility treatments over the last decade. This study aimed to examine the relationship between race/ethnicity and the utilization of different infertility treatments over the previous decade. We conducted this retrospective cohort study using the United States (US) Birth data files 2011-2019. We calculated the rates of infertility treatment and its subtypes over the study period. Descriptive statistics were utilized to examine the sociodemographic and birth characteristics for overall births and those associated with any infertility treatment and each of its subtypes. We calculated the level of association between race/ethnicity and utilization of infertility treatment and the subtypes using adjusted logistic regression models. We found that the rate of infertility treatments for all subtypes considered, had steadily increased by 63.7% within the past decade. In contrast, fertility enhancing drugs or Intrauterine Insemination (IUI) increased by 134%, and in vitro fertilization (IVF), gamete intrafallopian transfer (GIFT), and zygote intrafallopian transfer (ZIFT) treatments increased by 40% over the 9-year study period. Non-Hispanic (NH) Asian women had the highest rate of any infertility treatment with a rate of 25 per 1000 births whereas Hispanic women had the lowest rate of any infertility treatment at 5.8 per 1000 births. When compared with NH-White women, NH-Asian women had a modest 7% lower likelihood (OR = 0.93, 95% CI = 0.92-0.94) of receiving any infertility treatment while NH-Black and Hispanic women had about 70% lower likelihood of receiving any infertility treatment. Our report of increased assisted reproductive technology (ART) utilization rates, and marked racial/ethnic differences in ART utilization highlight the importance of expanding knowledge of inequities that continue to impact marginalized groups, a critical step for informing actionable strategy formulations (i.e., advocacy, policy change, patient education, provider training) to address these inequities.

Association of adverse birth outcomes with in vitro fertilization after controlling infertility factors based on a singleton live birth cohort

Infants conceived with in vitro fertilization (IVF) are exposed to underlying infertility and the IVF process. High risks of adverse birth outcomes (ABOs) were observed among these infants, including preterm birth, low birth weight, macrosomia, being large/small for gestational age (LGA/SGA). It is unclear whether the specific etiology of the rise of ABOs among IVF infants is IVF technology itself or underlying infertility. A total of 9,480 singletons conceived with IVF and 1,952,419 singletons from the general population were obtained in this study. Multivariable logistic regression model was used to assess variations in risk of ABOs according to causes of infertility. Poisson distributions were applied to calculate standardized risk ratios of IVF infants vs. general population after controlling the causes of infertility. Higher risk of preterm birth and low birth weight were observed among parents with polycystic ovary syndrome, endometriosis, uterine and semen abnormalities. Compared to the general population, after excluding the influence of infertility causes, singletons conceived with IVF were at higher risk of macrosomia (SRR = 1.28, 95% CI 1.14-1.44) and LGA (SRR = 1.25, 95% CI 1.15-1.35). The higher risk of ABOs in IVF was driven by both IVF treatments and infertility, which is important for improving IVF treatments and the managing pregnancies and child development.

OUP accepted manuscript

STUDY QUESTION

Are there differences in thyroid function between adolescents and young adults conceived with and without ART?

SUMMARY ANSWER

This study demonstrated no evidence of clinically relevant differences in thyroid function between adolescents and young adults conceived with and without ART.

WHAT IS KNOWN ALREADY

Studies to date have reported an increase in subclinical hypothyroidism in offspring conceived after ART. It has been suggested that the increase in maternal estrogen (E2) after fresh embryo transfers could affect thyroid function of the offspring. Suboptimal thyroid function at a young age can cause irreversible damage to the central nervous system, which makes early detection and correct treatment essential.

STUDY DESIGN, SIZE, DURATION

The Growing Up Healthy Study (GUHS) is a prospective cohort study, which aimed to recruit all adolescents born after conception with ART between 1991 and 2001 in the study area. The included participants (n = 303, aged 13–20 years) completed various health assessments. Depending on the age at enrolment, participants completed thyroid assessments at the 14- or 20-year follow-up. The outcomes of these replicated thyroid assessments were compared to those of participants conceived without ART from the Raine Study Generation 2 (Gen2). The Gen2 participants (n = 2868) were born between 1989 and 1992 and have been recognized to be representative of the local population.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Thyroid function assessments were compared between n = 134 GUHS and n = 1359 Gen2 adolescents at age 14 years and between n = 47 GUHS and n = 914 Gen2 young adults at age 20 years. The following mean thyroid hormone concentrations were compared between the cohorts: thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4) and thyroid peroxidase antibodies (TPOAb). The prevalence of the following thyroid hormone profiles, based on individual thyroid hormone concentrations, was compared: euthyroidism, subclinical and overt hypo- and hyperthyroidism and thyroid autoimmunity. Outcomes were compared between the cohorts, and univariately between fresh embryo transfers (ET) and frozen ET (FET) within the GUHS. The correlation between maternal peak E2 concentrations (pE2) and fT4 was assessed within the GUHS.

MAIN RESULTS AND THE ROLE OF CHANCE

All mean thyroid function outcomes fell within the normal range. At both ages, we report no differences in TSH concentrations. At age 14 years, lower fT3 concentrations (4.80 versus 5.35 pmol/L, P < 0.001) and higher fT4 concentrations (12.76 versus 12.19 pmol/L, P < 0.001) were detected in the GUHS adolescents compared to Gen2 adolescents. At age 20 years, higher fT3 and fT4 concentrations were reported in GUHS adolescents (4.91 versus 4.63 pmol/L, P = 0.012; 13.43 versus 12.45 pmol/L, P < 0.001, respectively) compared to Gen2 participants. No differences in the prevalence of subclinical and overt hypo- and hyperthyroidism or thyroid autoimmunity were demonstrated between the cohorts at age 14 and 20 years. Thyroid function did not differ between ET and FET, and no correlation between pE2 and fT4 was reported.

LIMITATIONS, REASONS FOR CAUTION

The observational nature of the study limits the ability to prove causation. Furthermore, the comparison of ET and FET offspring at age 20 years may be lacking power. We were unable to differentiate between different types of ART (e.g. IVF versus ICSI) owing to the low number of ICSI cycles at the time of study. As ART laboratory and clinic data were collected contemporaneously with the time of treatment, no other data pertaining to the ART cycles were sought retrospectively; hence, some factors could not be accounted for.

WIDER IMPLICATIONS OF THE FINDINGS

This study does not support previous findings of clinically relevant differences in thyroid function when comparing a cohort of adolescents conceived after ART to counterparts conceived without ART. The minor differences detected in fT3 and fT4 were considered not biologically relevant. Although these findings appear reassuring, they warrant reinvestigation in adulthood.

STUDY FUNDING/COMPETING INTERESTS

This project was funded by an NHMRC Grant (Hart et al., ID 1042269). R.J.H. is the Medical Director of Fertility Specialists of Western Australia and a shareholder in Western IVF. He has received educational sponsorship from MSD, Merck-Serono and Ferring Pharmaceuticals. P.B. is the Scientific Director of Concept Fertility Centre, Subiaco, Western Australia. J.L.Y. is the Medical Director and a shareholder of PIVET Medical Centre, Perth, Western Australia.

TRIAL REGISTRATION NUMBER

N/A.

Reproductive Outcome After GnRH Agonist Triggering With Co-Administration of 1500 IU hCG on the Day of Oocyte Retrieval in High Responders: A Long-Term Retrospective Cohort Study

While triggering oocyte maturation with GnRH agonist (GnRHa) seems to be safe and effective in terms of the risk of developing OHSS and the number of metaphase II oocytes, it nevertheless results in luteal phase deficiency. To date, strategies have been developed in order to rescue defective luteal phase of GnRHa triggered cycles. Our study aimed to assess the reproductive outcome of GnRHa triggered cycles combined with modified luteal support (1500 IU hCG at the day of oocyte retrieval) in women with high ovarian response and to compare the outcome with hCG triggered cycles in GnRH antagonist IVF-ICSI procedures. A retrospective cohort database review of the results of GnRH antagonist IVF-ICSI cycles was conducted at a tertiary-care IVF center in Ljubljana, Slovenia. A total of 6126 cycles, performed from January 1, 2014, to December 31, 2020, were included in the final analysis. Final oocyte maturation was performed with either 5000, 6500, or 10,000 IU hCG (women with normal ovarian response) or 0.6 mg GnRHa (buserelin), supplemented with 1500 IU hCG on the day of oocyte retrieval (in women with high ovarian response). In cases of excessive ovarian response and/or high risk of OHSS luteal support was not introduced and all good quality blastocysts were frozen. According to significant differences in patients' age and the number of oocytes in the two groups, matching by age and number of oocytes was performed. No significant differences were observed regarding pregnancy rate per embryo transfer, rate of early pregnancy loss, and livebirth rate per pregnancy between the GnRHa and hCG trigger groups, respectively. A significant difference in the number of developed embryos and blastocysts, as well as the number of frozen blastocysts, was seen in favor of the GnRHa trigger. However, the birth weight in the GnRHa trigger group was significantly lower.

CONCLUSION

The results of our study support the use of GnRHa for final oocyte maturation in GnRH antagonist IVF cycles in women with high ovarian response. Luteal phase rescue was performed by co-administration of 1500 IU hCG on the day of oocyte retrieval and estradiol and progesterone supplementation. In our experience, such an approach results in a comparable reproductive outcome with hCG trigger group.

Infertility treatment and the risk of small for gestational age births: a population-based study in the United States

Objective

To evaluate the association between infertility treatments and small for gestational age (SGA) births.

Design

Cross-sectional study.

Setting

United States, 2015–2019.

Patient(s)

Women (n = 16,836,228) who delivered nonmalformed, singleton live births (24–44 weeks’ gestation).

Intervention(s)

Any infertility treatment, including assisted reproductive technology (ART) and prescribed fertility-enhancing medications.

Main Outcome Measure(s)

Small for gestational age birth, defined as sex-specific birth weight <10% for gestational age. Associations between SGA and infertility treatment were derived from Poisson regression with robust variance. Risk ratios (RR) and 95% confidence intervals (CI) were derived after adjusting for confounders. In a sensitivity analysis, we corrected for nondifferential exposure misclassification and unmeasured confounding biases.

Result(s)

Subsequently, 1.4% (n = 231,177) of pregnancies resulted from infertility treatments (0.8% ART and 0.6% fertility-enhancing medications). Of these, SGA births occurred in 9.4% (n = 21,771) and 11.9% (n = 1,755,925) of pregnancies conceived with infertility treatment and naturally conceived pregnancies, respectively (adjusted RR, 1.07; 95% CI, 1.06, 1.08). However, after correction for misclassification bias and unmeasured confounding, infertility treatment was associated with a 27% reduced risk of SGA (bias-corrected RR, 0.73; 95% CI, 0.53, 0.85). Similar trends were seen for analyses stratified by exposure to ART and fertility-enhancing medications, as well as for SGA <5th and <3rd percentiles.

Conclusion(s)

Exposure to infertility treatment is associated with a reduced risk of SGA births. These findings, which are contrary to some published reports, may reflect changes in the modern practice of infertility care, maternal lifestyle, and compliance with prenatal care within the infertile population. Until these findings are corroborated, the associations must be cautiously interpreted.

Maternal and neonatal outcomes following in vitro fertilization: A cohort study in Romania

Although in recent years the number of pregnancies obtained through in vitro fertilization (IVF) has increased significantly, a higher incidence of complications has been identified in this group. The widespread development and use of IVF has led to an increasing rate of multiple pregnancies and thus their associated complications. However, whether these complications occur due to assisted reproduction or infertility problems remains to be elucidated. In the present study, a comparison was made of IVF pregnancies with spontaneous conception, and the risk of obstetric and neonatal complications was assessed. An ambispective observational cohort study was carried out between January 2017 and October 2021 at Elias University Emergency Hospital, Romania. The exposed cohort included 132 IVF pregnancies and the control cohort included 157 spontaneous pregnancies. The IVF group included 110 pregnancies with fresh embryo-transfer and 22 pregnancies with cryopreserved embryo-transfer. Obstetric, perinatal and neonatal complications were analysed by multivariable logistic analysis. The results showed that, IVF pregnancies had a higher risk of pregnancy-induced hypertension (OR=6.42, 95% CI=1.72-23.92) and placental abnormalities (OR=5.49, 95% CI=1.07-28.17). Neonates obtained through IVF had a higher risk of prematurity (OR=6.52, 95% CI=2.99-14.20), low birth weight (LBW) (OR=17.18, 95% CI=7.06-41.87), small for gestational age (OR=4.10, 95% CI=1.95-8.59) and were more frequently hospitalized in the Neonatal Intensive Care Unit (NICU) (OR=11.91, 95% CI=5.72-24.81). Nulliparous women were associated with an increased risk of NICU admission (OR=0.46, 95% CI=0.25-0.88) and risk of LBW (OR=0.37, 95% CI=0.19-0.75). Maternal age ≥35 years had no influence as a confounding variable. In conclusion, this cohort study showed that IVF pregnancies have a higher risk of obstetric and neonatal complications than pregnancies obtained by spontaneous conception.

A prospective cohort study providing insights for markers of adverse pregnancy outcome in older mothers

Background

Advanced maternal age (≥35 years) is associated with increased rates of adverse pregnancy outcome. Better understanding of underlying pathophysiological processes may improve identification of older mothers who are at greatest risk. This study aimed to investigate changes in oxidative stress and inflammation in older women and identify clinical and biochemical predictors of adverse pregnancy outcome in older women.

Methods

The Manchester Advanced Maternal Age Study (MAMAS) was a multicentre, observational, prospective cohort study of 528 mothers. Participants were divided into three age groups for comparison 20–30 years (n = 154), 35–39 years (n = 222) and ≥ 40 years (n = 152). Demographic and medical data were collected along with maternal blood samples at 28 and 36 weeks’ gestation. Multivariable analysis was conducted to identify variables associated with adverse outcome, defined as one or more of: small for gestational age (< 10th centile), FGR (<5th centile), stillbirth, NICU admission, preterm birth < 37 weeks’ gestation or Apgar score < 7 at 5 min. Biomarkers of inflammation, oxidative stress and placental dysfunction were quantified in maternal serum. Univariate and multivariable logistic regression was used to identify associations with adverse fetal outcome.

Results

Maternal smoking was associated with adverse outcome irrespective of maternal age (Adjusted Odds Ratio (AOR) 4.22, 95% Confidence Interval (95%CI) 1.83, 9.75), whereas multiparity reduced the odds (AOR 0.54, 95% CI 0.33, 0.89). In uncomplicated pregnancies in older women, lower circulating anti-inflammatory IL-10, IL-RA and increased antioxidant capacity (TAC) were seen. In older mothers with adverse outcome, TAC and oxidative stress markers were increased and levels of maternal circulating placental hormones (hPL, PlGF and sFlt-1) were reduced (p < 0.05). However, these biomarkers only had modest predictive accuracy, with the largest area under the receiver operator characteristic (AUROC) of 0.74 for placental growth factor followed by TAC (AUROC = 0.69).

Conclusions

This study identified alterations in circulating inflammatory and oxidative stress markers in older women with adverse outcome providing preliminary evidence of mechanistic links. Further, larger studies are required to determine if these markers can be developed into a predictive model of an individual older woman’s risk of adverse pregnancy outcome, enabling a reduction in stillbirth rates whilst minimising unnecessary intervention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04178-6.

Obstetric and neonatal outcomes of pregnancies resulting from preimplantation genetic testing: a systematic review and meta-analysis

BACKGROUND

Preimplantation genetic testing (PGT) includes methods that allow embryos to be tested for severe inherited diseases or chromosomal abnormalities. In addition to IVF/ICSI and repeated freezing and thawing of the embryos, PGT requires a biopsy to obtain embryonic genetic material for analysis. However, the potential effects of PGT on obstetric and neonatal outcomes are currently uncertain.

OBJECTIVE AND RATIONALE

This study aimed to investigate whether pregnancies conceived after PGT were associated with a higher risk of adverse obstetric and neonatal outcomes compared with spontaneously conceived (SC) pregnancies or pregnancies conceived after IVF/ICSI.

SEARCH METHODS

PubMed, EMBASE, MEDLINE, Web of Science and The Cochrane Library entries from January 1990 to January 2021 were searched. The primary outcomes in this study were low birth weight (LBW) and congenital malformations (CMs), and the secondary outcomes included gestational age, preterm delivery (PTD), very preterm delivery (VPTD), birth weight (BW), very low birth weight (VLBW), neonatal intensive care unit (NICU) admission, hypertensive disorders of pregnancy (HDP), gestational diabetes, placenta previa and preterm premature rupture of membranes (PROM). We further pooled the results of PGT singleton pregnancies. Subgroup analyses included preimplantation genetic diagnosis (PGD), preimplantation genetic screening (PGS), cleavage-stage biopsy combined with fresh embryo transfer (CB-ET) and blastocyst biopsy combined with frozen-thawed embryo transfer (BB-FET).

OUTCOMES

This meta-analysis included 15 studies involving 3682 babies born from PGT pregnancies, 127 719 babies born from IVF/ICSI pregnancies and 915 222 babies born from SC pregnancies. The relative risk (RR) of LBW was higher in PGT pregnancies compared with SC pregnancies (RR = 3.95, 95% confidence interval [CI]: 2.32-6.72), but the risk of CMs was not different between the two groups. The pooled results for the risks of LBW and CMs were similar in PGT and IVF/ICSI pregnancies. The risks of PTD (RR = 3.12, 95% CI: 2.67-3.64) and HDP (RR = 3.12, 95% CI: 2.18-4.47) were significantly higher in PGT pregnancies compared with SC pregnancies. Lower gestational age (mean difference [MD] = -0.76 weeks, 95% CI -1.17 to -0.34) and BW (MD = -163.80 g, 95% CI: -299.35 to -28.24) were also noted for PGT pregnancies compared with SC pregnancies. Nevertheless, compared with IVF/ICSI pregnancies, the risks of VPTD and VLBW in PGT pregnancies were significantly decreased by 41% and 30%, respectively, although the risk of HDP was still significantly increased by 50% in PGT pregnancies compared with IVF/ICSI pregnancies. The combined results of obstetric and neonatal outcomes of PGT and IVF/ICSI singleton pregnancies were consistent with the overall results. Further subgroup analyses indicated that both PGD and PGS pregnancies were associated with a higher risk of PTD and a lower gestational age compared with SC pregnancies.

WIDER IMPLICATIONS

This meta-analysis showed that PGT pregnancies may be associated with increased risks of LBW, PTD and HDP compared with SC pregnancies. The overall obstetric and neonatal outcomes of PGT pregnancies are favourable compared with those of IVF/ICSI pregnancies, although PGT pregnancies were associated with a higher risk of HDP. However, because the number of studies that could be included was limited, more randomised controlled trials and prospective cohort studies are needed to confirm these conclusions.

Asthma and allergies in offspring conceived by ART: a systematic review and meta-analysis

BACKGROUND

Currently, 1 in 25 children born in Australia are conceived through ARTs such as IVF and ICSI. Worldwide over 8 million children have been born after ART. There is evidence that these children are at an increased risk of congenital malformations, preterm birth, low birth weight and neonatal morbidity. However, studies on long-term health outcomes of offspring conceived after ART are lacking. Atopic disorders, such as asthma, atopic dermatitis and various allergies are increasingly common within society, and concerns have been raised that ART increases the risk of atopy amongst offspring.

OBJECTIVE AND RATIONALE

The aim of this study was to systematically summarise and quantify the risk of atopic disorders in offspring conceived with ART compared to those conceived without ART.

SEARCH METHODS

A systematic review was conducted according to the PRISMA guidelines. Several systematic searches were performed in the following international databases: Medline, Embase, Cinahl, PsychINFO, AMED, Global Health and ISI Web of Science. Search terms utilised were all terms pertaining to ART, IVF, ICSI, asthma, atopic dermatitis and allergies. The search period was 1978-2021. Included observational studies stated a primary outcome of asthma or allergies in offspring conceived after ART, with a comparison group conceived without ART. Individual studies were scored on quality and risk of bias, using the Newcastle-Ottawa scale (NOS).

OUTCOMES

There were 26 studies which met the inclusion criteria; of these, 24 studies investigated asthma in offspring conceived after ART. While 10 studies, including the two largest population-based studies, reported a significantly increased risk of asthma in offspring conceived after ART (adjusted odds ratio (aOR) range: 1.20-2.38), 14 smaller cohort studies found no difference (aOR range 0.70-1.27). In the meta-analysis of the 14 highest-quality studies (NOS ≥ 7), a modest yet significantly increased risk of asthma was demonstrated in offspring conceived after ART [risk ratio (RR) 1.28 (1.08-1.51)]. Although heterogeneity in these 14 studies was high (I2 = 85%), the removal of outliers and high weight studies significantly reduced heterogeneity (I2 = 0% and I2 = 34% respectively) while still demonstrating a significantly increased risk [RR 1.19 (1.10-1.28) and RR 1.31 (1.03-1.65), respectively]. The increased asthma risk was also observed in most subgroup and sensitivity analyses. The allergy rates were not increased in offspring conceived after ART in 9 of 12 studies (aOR range 0.60-1.30). In summary, the findings of this systematic review and meta-analysis suggest a trend towards a significantly increased risk of asthma, but not allergies, in offspring conceived after ART. There was no evidence of publication bias in the asthma studies and minimal evidence of publication bias in the allergy studies (both P > 0.05).

WIDER IMPLICATIONS

Asthma brings considerable burden to the quality of life of individuals and to society. Hence, it is of great importance to untangle potential causal pathways. Although ART use is common, knowledge about its long-term health effects is required to provide evidence-based advice to couples considering ART, and to be vigilant for any potential adverse health effects on offspring conceived after ART.

Examining pre-term birth and cesarean section rates in gestational carrier pregnancies

PURPOSE

This study sought to report on the route and gestational age at delivery of gestational carrier (GC) pregnancies with respect to the GCs' prior obstetric history.

METHODS

A retrospective analysis of all GC pregnancies from one of the largest surrogacy agencies in California between 2008 and 2018 was performed. Available demographic data and obstetric history, including a history of prior cesarean section (CS) and preterm birth (PTB), were collected for each GC and correlated to outcomes of the index GC pregnancy. Primary outcomes for the index GC pregnancies included delivery route and gestational age at delivery.

RESULTS

Eight-hundred-thirty-six GCs were included in our analysis. 319 (38.2%) delivered via CS, and 517 (61.8%) delivered vaginally. 60 (18.8%) of the CS deliveries were due to multifetal gestation. Primary CS rate in singleton GC pregnancies was 38.5%. In women without a history of CS, neither age, BMI, interpregnancy interval, prior parity, nor year of delivery impacted the primary singleton CS rate (all, P > 0.05). Of GCs with a history of a prior CS (n = 350, 41.9%), 218 (62.3%) had a vaginal delivery after CS (VBAC) and 132 (37.7%) had a repeat CS. Women who had successful VBACs were significantly younger than those who had repeat CS (mean 33.7 vs. 35.2 years, P = .003). BMI was lower in patients who had a VBAC compared to those that had a repeat CS (mean BMI 24.6 vs. 25.5, P = 0.074), although this did not reach statistical significance. In GCs with a history of CS, interpregnancy interval, year of delivery, prior parity, and multiple gestation in the index GC pregnancy did not impact mode of delivery. VBAC rates did not change over the study period (P = 0.757). Overall PTB rate was 15.1%. Most PTB in GC pregnancies were in those with a history of PTB, and PTB was more likely in singletons rather than multifetal gestations (76.7% in singletons vs. 30% in multiples) in patients with history of PTB (P < 0.001). Those with no history of PTB and who carried multiples had a low rate of PTB; in fact, in this group, only 1 out of 35 patients had a PTB with multiples.

CONCLUSIONS

Both primary CS and PTB rates in singleton GC pregnancies are higher than national averages. CS rates are independent of age, BMI, and interpregnancy interval. In GCs with a history of a CS, VBAC rates well exceed national averages and are higher in younger GCs with a lower BMI. PTB rates are impacted primarily by the GCs obstetric history. In those GCs without a history of PTB, rates of PTB are low, even in those with a multifetal gestation.

Outcomes of Very Preterm Infants Conceived with Assisted Reproductive Technologies

OBJECTIVE

To compare mortality and early respiratory outcomes of very preterm infants conceived via assisted reproductive technology (ART) vs spontaneously.

STUDY DESIGN

We identified inborn infants (July 2014-July 2019) with gestational age <32 weeks (n = 439); 54 cases were ART conceived. Spontaneously conceived controls (n = 103) were matched by multiple gestation status and gestational age. Primary outcome was 1-year mortality. Secondary outcomes were receipt of respiratory support and supplemental oxygen at 7 and 28 days and 36 weeks of postmenstrual age. We evaluated the association between conception method and outcomes by logistic regression, with adjustment for sociodemographic status.

RESULTS

Women who conceived via ART had increased rates of prepregnancy and gestational diabetes, and no differences in rates of hypertensive disorders. Infant 1-year mortality was not different by mode of conception (ART 11.8% vs spontaneous 7.1%, P = .49). Infants conceived by ART were less likely to receive respiratory support or supplemental oxygen at all time points, but this relationship only reached significance for receipt of oxygen at 28 days (ART 20.8% vs spontaneous 39.0%, P = .03); this remained true after adjustment for race/ethnicity and socioeconomic index.

CONCLUSIONS

When controlling for gestational age and multiple gestation status, very preterm infants conceived following ART had similar outcomes as those conceived spontaneously.

Ovarian stimulation reduces fetal growth by dysregulating uterine natural killer cells in mice

Ovarian stimulation is associated with a higher risk of low birth weight. However, the precise mechanisms by which ovarian stimulation increases the chances of low birth weight remain unclear. In this mouse model study, in vivo developed blastocysts that were not exposed to gonadotropins were transferred into pseudopregnant females that had mated naturally (the control group), pseudopregnant females that had been administered a low dose of ovulation-stimulating hormone (the L-SO group) and pseudopregnant females that had been administered a high dose of ovulation-stimulating hormone (the H-SO group). The embryo implantation rate and fetal weight were significantly lower in the L-SO and H-SO groups than in the control group. The density of Dolichos biflorus agglutinin (DBA)⁺ uterine natural killer (uNK) cells in the decidua basalis was significantly lower in the L-SO and H-SO groups than in the control group. Ovarian stimulation also downregulated a variety of cytokines related to uNK cells that are involved in placental angiogenesis and trophoblast invasion. Collectively, our findings indicate that ovarian stimulation impairs DBA⁺ uNK cell density in the decidua basalis, which may downregulate uNK-related cytokine secretion and influence placental angiogenesis and restrict fetal growth in mice.

Obstetric outcomes in pregnancies resulting from in vitro fertilization are not different in fertile, sterilized women compared to infertile women: A Society for Assisted Reproductive Technology database analysis

OBJECTIVE

To compare obstetric and neonatal outcomes resulting from assisted reproductive technology in couples with a history of female sterilization to couples with other infertility diagnoses.

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

Fresh, nondonor cycles excluding gestational surrogacy from 2004 to 2013 in the United States.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Preterm birth rates and low birth weight rates from in vitro fertilization (IVF) pregnancies in couples with infertility and in couples with prior tubal ligation as their sole indication for IVF.

RESULT(S)

The mean ages of fertile women (N = 8,478) and infertile women (N = 371,488) were 35.3 and 34.6 years, respectively. Of the singletons born to parous women (N = 26,463), the incidence of preterm birth was not significantly different in fertile, sterilized couples compared to infertile couples (13.7% vs. 12.0%). The incidence of low birth weight among term singletons was also not significantly different between fertile couples compared to infertile couples (3.5% vs. 3.2%).

CONCLUSION(S)

Fertile couples have similar preterm birth and low birth weight rates after IVF compared to infertile couples. This suggests that differences in perinatal outcomes may be due to assisted reproductive technology procedures rather than infertility itself.

Alteration of Genomic Imprinting after Assisted Reproductive Technologies and Long-Term Health

Assisted reproductive technologies (ART) are the treatment of choice for some infertile couples and even though these procedures are generally considered safe, children conceived by ART have shown higher reported risks of some perinatal and postnatal complications such as low birth weight, preterm birth, and childhood cancer. In addition, the frequency of some congenital imprinting disorders, like Beckwith-Wiedemann Syndrome and Silver-Russell Syndrome, is higher than expected in the general population after ART. Experimental evidence from animal studies suggests that ART can induce stress in the embryo and influence gene expression and DNA methylation. Human epigenome studies have generally revealed an enrichment of alterations in imprinted regions in children conceived by ART, but no global methylation alterations. ART procedures occur simultaneously with the establishment and maintenance of imprinting during embryonic development, so this may underlie the apparent sensitivity of imprinted regions to ART. The impact in adulthood of imprinting alterations that occurred during early embryonic development is still unclear, but some experimental evidence in mice showed higher risk to obesity and cardiovascular disease after the restriction of some imprinted genes in early embryonic development. This supports the hypothesis that imprinting alterations in early development might induce epigenetic programming of metabolism and affect long-term health. Given the growing use of ART, it is important to determine the impact of ART in genomic imprinting and long-term health.