Fetal cardiac function at midgestation and conception by in-vitro fertilization

OBJECTIVE

To assess differences in cardiac morphology and function at midgestation in fetuses conceived by in-vitro fertilization (IVF), using fresh or frozen embryo transfer, compared with those conceived naturally.

METHODS

This was a prospective study of 5801 women with a singleton pregnancy attending for a routine ultrasound examination at 19 + 0 to 23 + 6 weeks' gestation, including 343 that conceived by IVF. Conventional and more advanced echocardiographic modalities, including speckle-tracking analysis, were used to assess fetal cardiac function in the right and left ventricles. The morphology of the fetal heart was assessed by calculating the right and left sphericity index. Placental perfusion and function were assessed by measurement of uterine artery pulsatility index (UtA-PI) and serum placental growth factor (PlGF), respectively.

RESULTS

Fetuses that were conceived by IVF, compared with those conceived spontaneously, had significantly lower right and left ventricular sphericity index, higher left ventricular global longitudinal strain and lower left ventricular ejection fraction. There were no significant differences in any of the cardiac indices within the IVF group between the fresh and frozen embryo transfers. In the IVF group, compared with spontaneously conceived pregnancies, UtA-PI was lower and PlGF was higher, suggesting better placental perfusion and function.

CONCLUSIONS

Our study demonstrates that, in IVF pregnancies, compared with those conceived spontaneously, there is evidence of fetal cardiac remodeling at midgestation, which is not related to the use of fresh or frozen embryo transfer. In the IVF group, compared with naturally conceived pregnancies, fetal heart was globular and left ventricular systolic function was mildly reduced. Whether these cardiac changes are accentuated later in pregnancy and remain in the postnatal period remains to be established. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Expression of Toll-Like Receptors in the Lung Tissue of Mouse Fetuses Generated by in vitro Embryo Culture and Embryo Transfer

Mouse fetuses generated by in vitro embryo culture and embryo transfer exhibit impaired lung development, altered composition of pulmonary epithelial cells associated with downregulation of several genes involved in lung development and toll-like receptor (TLR) signaling pathway. The aims of the present study were to determine the expression of all TLRs and to examine if the expression of TLRs, along with genes involved in TLR signaling pathway, is altered in the lung tissue of mouse fetuses generated through embryo culture and embryo transfer. Two experimental (EGs) and one control (CG) group were included in the study. Embryos cultured at 5% CO2-95% air for 95 h or less than 24 h were transferred to pseudo-pregnant females to obtain fetuses comprising EGin vitro (n = 18) and EGin vivo (n = 18), respectively. Fetuses obtained from naturally ovulating females on day 18 of pregnancy served as the CG (n = 18). Western blot and immunohistochemistry were used to determine the expression of TLR proteins. The expression of transcripts encoding TLRs, and the genes involved in TLR signaling pathway (Lbp, Pik3r1, Pik3cb, Nfkbia, and Fos), was determined using qRT-PCR. While all TLRs were expressed by cells lining the bronchial/bronchiolar epithelium of lung tissues in all groups, some of the TLRs were expressed in a specific pattern. When compared to CG, the expression of transcripts encoding TLR-2, -3, -4, -5, -7, -8, -9, -12, -13, Lbp, Pik3r1, Pik3cb, Nfkbia, and Fos was significantly downregulated in both EGs. It appears that stress imposed on embryos at preimplantation stages of development is associated with downregulation of TLRs, along with some of the genes involved in TLR signaling pathway, in the lung tissue during the perinatal period. It remains to be determined if downregulation of TLRs, along with the genes involved in TLR signaling pathway, has any functional consequences in the adult lung tissue.

Effect of increased gonadotropin dosing on maternal and neonatal outcomes in predicted poor responders undergoing IVF: follow-up of a randomized trial

OBJECTIVE

To evaluate, in women scheduled for IVF with predicted poor ovarian response, the effect of increased dosing of gonadotropin on maternal and neonatal outcomes compared with standard dosing.

STUDY DESIGN

We performed a follow-up study of an open-labelled randomized controlled trial comparing increased (225 or 300 IU/d) versus standard (150 IU/d) dose gonadotrophins on cumulative live birth rates. We randomized 661 women with a predicted poor ovarian response (based on their antral follicle count) scheduled for their first IVF/ICSI cycle. Here, we report on maternal and neonatal outcomes between increased and standard dosing groups.

RESULTS

There was a trend of increased risk of gestational diabetes mellitus in the increased gonadotrophin dose group compared with the standard group in both cumulative live birth pregnancies (14.8% vs. 7.8%, relative risk (RR) 1.90, 95% confidence interval (CI) 0.96-3.74, P = 0.06) and live birth pregnancies in the first transfer (15.2% vs. 7.7%, RR 1.98, 95 %CI 0.93-4.19, P = 0.08), without reaching statistical significance. The occurrence of gestational diabetes mellitus was significantly higher in the increased gonadotrophin dose group (24/149, 16.1% vs. 8/128, 6.3%; risk ratio (RR) 2.58, 95 %CI 1.19 to 5.54, P = 0.02) in singleton pregnancies. In women with first embryo transfer cycle, maternal hypothyroidism occurred also more frequent in the increased gonadotrophin dose group than the standard group (16.0% vs. 6.8%, RR 2.34, 95 %CI:1.07-5.11, P = 0.03).

CONCLUSIONS

In women with predicted poor ovarian response, increased dosing of gonadotropin may result in an increased risk of gestational diabetes mellitus and maternal hypothyroidism.

Chronic poor healing wounds of post cesarean scar diverticulum: Altered angiogenesis and immunobiology

Cesarean section (CS) scar diverticula (CSD) is an important cause impede further fecundity, with rather complicated pathophysiologic mechanisms and unclear etiopathogenesis. In this study, we detect the influences of CSD on the pregnancy outcomes in in-vitro fertilization (IVF) or intra-cytoplasmic sperm injection (ICSI) embryo transfer (ET) cycles, and further explore the mechanisms involved based on histopathology and immunology differences in endometrium between CSD and vaginal birth (VB) women. The CS group had significantly lower CLBR compared to NCS group. Histopathological analysis showed that the higher prevalent of CE is accompanied by excessive fibroblast proliferation at the lower segment of uterus and significantly exaggerated vascular proliferation in situ. Intrauterine inflammatory cytokines including IL-1α, IL-1β, IL-6, IL-8, TNF-α and SDF-1α were also increased in CSD group. The present data suggests impaired fecundity in CSD women undergoing IVF/ICSI treatment. Although the causal relationship is ambiguous, the potential mechanisms may involve persistent inflammatory response in the uterine cavity, active vascular proliferation accompanied with increased fibrosis which are responsible for poor chronic wound healing of CSD.

Dynamics of gametes and embryos in the oviduct: what can in vivo imaging reveal?

In brief

In vivo imaging of gametes and embryos in the oviduct enables new studies of the native processes that lead to fertilization and pregnancy. This review article discusses recent advancements in the in vivo imaging methods and insights which contribute to understanding the oviductal function.

Abstract

Understanding the physiological dynamics of gametes and embryos in the fallopian tube (oviduct) has significant implications for managing reproductive disorders and improving assisted reproductive technologies. Recent advancements in imaging of the mouse oviduct in vivo uncovered fascinating dynamics of gametes and embryos in their native states. These new imaging approaches and observations are bringing exciting momentum to uncover the otherwise-hidden processes orchestrating fertilization and pregnancy. For mechanistic investigations, in vivo imaging in genetic mouse models enables dynamic phenotyping of gene functions in the reproductive process. Here, we review these imaging methods, discuss insights recently revealed by in vivo imaging, and comment on emerging directions, aiming to stimulate new in vivo studies of reproductive dynamics.

Risk factors associated with preterm birth in singletons born after IVF: a national cohort study

RESEARCH QUESTION

What are the risk factors for prematurity other than intrauterine growth restriction in singletons after IVF?

DESIGN

Data were collected from a national registry, based on an observational prospective cohort of 30,737 live births after assisted reproductive technology (fresh embryo transfers: n = 20,932 and frozen embryo transfer [FET] n = 9805) between 2014 and 2015. A population of not-small for gestational age singletons conceived after fresh embryo transfers and FET, and their parents, was selected. Data on a number of variables were collected, including type of infertility, number of oocytes retrieved and vanishing twins.

RESULTS

Preterm birth occurred in 7.7% (n = 1607) of fresh embryo transfers and 6.2% (n = 611) of frozen-thawed embryo transfers (P < 0.0001; adjusted odds ratio [aOR] = 1.34 [1.21-1.49]). Endometriosis and vanishing twin increased the risk of preterm birth after fresh embryo transfer (P < 0.001; aOR 1.32 and 1.78, respectively). Polycystic ovaries or more than 20 oocytes retrieved also increased preterm birth risk (aOR 1.31 and 1.30; P = 0.003 and P = 0.02, respectively); large oocyte cohort (>20) was no longer associated with the risk of prematurity in FET.

CONCLUSION

Endometriosis remains a risk for prematurity even in the absence of intrauterine growth retardation, which suggests a dysimmune effect. Large oocyte cohorts obtained by stimulation, without clinical polycystic ovary syndrome diagnosed before attempts, do not affect FET outcomes, reinforcing the idea of a phenotypic difference in the clinical presentation of polycystic ovary syndrome.

Maternal gestational diabetes in singleton pregnancies conceived by ART may be modified by periconceptional B vitamins

Background

The risk of maternal gestational diabetes mellitus (GDM) may be influenced by pregnancies conceived through assisted reproductive technology (ART). However, the influence of the dosage of B vitamins (folate, vitamin B6 and vitamin B12) on GDM weren't considered. Thus, we hypothesized that periconceptional B vitamins could modify maternal GDM in singleton pregnancies conceived by ART.

Methods

This study is a prospective cohort study using data from 3,252 women with singleton pregnancies and received a 75 g oral glucose tolerance test (OGTT) at 24-28 weeks of gestation. We included an interaction term in the multivariable logistic and linear regression models, respectively, to test our hypothesis.

Results

Women who underwent ART were significantly associated with the incidence of GDM compared with spontaneous pregnancy women. The adjusted odds ratio (aOR) was 1.59, and the 95% confidence interval (CI) was 1.08-2.34. ART pregnancies also elevated OGTT (oral glucose tolerance test) 1-h blood glucose levels and OGTT 2-h blood glucose levels (P < 0.05). A positive association between dietary vitamin B6 (aOR = 1.60, 95% CI: 1.13-2.27), dietary vitamin B12 (aOR = 1.88, 95% CI: 1.34-2.64) and dietary folate (aOR = 1.66, 95% CI: 1.19-2.32) with GDM risk comparing the highest to the lowest quartile (all P _trend < 0.001). The aORs of GDM for inadequate (< 400 μg/day), adequate (400-800 μg/day), and excessive (> 800 μg/day) supplemental folate intake were 1.00, 0.93, and 1.30, respectively (P _trend = 0.033). Since only the supplemental folate illustrates a statistically significant interaction with ART (P for interaction < 0.05), the association between ART and GDM and OGTT blood glucose levels stratifying by supplemental folate were further evaluated. These increased risks of GDM (aOR = 1.62, 95% CI: 1.39-3.39) and the regression coefficients (β) of 1-h blood glucose (β = 0.76, 95% CI: 0.39-1.13) and 2-h blood glucose (β = 0.60, 95% CI: 0.29-0.92) in the multiple linear regression model were significant only in the ART group with excessive supplemental folate (> 800 μg/day).

Conclusion

The risk of GDM is significantly elevated, particularly among those women who conceived ART with the intake of excessive supplemental folate (> 800 μg/day).

Genome-wide assessment of DNA methylation alterations induced by superovulation, sexual immaturity and in vitro follicle growth in mouse blastocysts

BACKGROUND

In their attempt to fulfill the wish of having children, women who suffer from fertility issues often undergo assisted reproductive technologies such as ovarian stimulation, which has been associated with adverse health outcomes and imprinting disorders in children. However, given the crucial role of exogenous hormone stimulation in improving human infertility treatments, a more comprehensive analysis of the potential impacts on DNA methylation in embryos following ovarian stimulation is needed. Here, we provide genome-wide DNA methylation profiles of blastocysts generated after superovulation of prepubertal or adult mice, compared with blastocysts derived from non-stimulated adult mice. Additionally, we assessed the impact of the in vitro growth and maturation of oocytes on methylation in blastocysts.

RESULTS

Neither hormone stimulation nor sexual maturity had an impact on the low global methylation levels characteristic of the blastocyst stage or was associated with extensive DNA methylation alterations. However, we found hormone- and age-associated changes at specific positions but dispersed throughout the genome. In particular, we detected anomalous methylation at a limited number of CpG islands. Additionally, superovulation in adult mice was associated with alterations at the Sgce and Zfp777 imprinted genes. On the other hand, in vitro culture of follicles from the early pre-antral stage was associated with globally reduced methylation and increased variability at imprinted loci in blastocysts.

CONCLUSIONS

Our results indicate a minimal effect of ovarian stimulation of adult and prepubertal mice on the DNA methylation landscape attained at the blastocyst stage, but potentially greater impacts of in vitro growth and maturation of oocytes. These findings have potential significance for the improvement of assisted reproductive techniques, in particular for those related to treatments in prepubertal females, which could be crucial for improving human fertility preservation strategies.

John JC. Does supplementation of oocytes with additional mtDNA influence developmental outcome?

Introducing extra mitochondrial DNA (mtDNA) into oocytes at fertilization can rescue poor quality oocytes. However, supplementation alters DNA methylation and gene expression profiles of preimplantation embryos. To determine if these alterations impacted offspring, we introduced mtDNA from failed-to-mature sister (autologous) or third party (heterologous) oocytes into mature oocytes and transferred zygotes into surrogates. Founders exhibited significantly greater daily weight gain (heterologous) and growth rates (heterologous and autologous) to controls. In weaners, cholesterol, bilirubin (heterologous and autologous), anion gap, and lymphocyte count (autologous) were elevated. In mature pigs, potassium (heterologous) and bicarbonate (autologous) were altered. mtDNA and imprinted gene analyses did not reveal aberrant profiles. Neither group exhibited gross anatomical, morphological, or histopathological differences that would lead to clinically significant lesions. Female founders were fertile and their offspring exhibited modified weight and height gain, biochemical, and hematological profiles. mtDNA supplementation induced minor differences that did not affect health and well-being.

Fetal growth disorders following medically assisted reproduction: due to maternal context or techniques? A national French cohort study

RESEARCH QUESTION

What part do maternal context and medically assisted reproduction (MAR) techniques play in the risk of fetal growth disorders?

DESIGN

This retrospective nationwide cohort study uses data available in the French National Health System database and focuses on the period from 2013 to 2017. Fetal growth disorders were divided into four groups according to the origin of pregnancy: fresh embryo transfer (n = 45,201), frozen embryo transfer (FET, n = 18,845), intrauterine insemination (IUI, n = 20,179) and natural conceptions (n = 3,412,868). Fetal growth disorders were defined from the percentiles of the weight distribution according to gestational age and sex: small and large for gestational age (SGA and LGA) if <10th and >90th percentiles, respectively. Analyses were performed using univariate and multivariate logistic models.

RESULTS

Compared with births following natural conception, multivariate analysis showed that the risk of SGA was higher for births following fresh embryo transfer and IUI (adjusted odds ratio [aOR] 1.26 [1.22-1.29] and 1.08 [1.03-1.12], respectively) and significantly lower following FET (aOR 0.79 [0.75-0.83]). The risk of LGA was higher for births following FET (aOR 1.32 [1.27-1.38]), especially in artificial cycles when compared with ovulatory cycles (aOR 1.25 [1.15-1.36]). In the subgroup of births without any obstetrical or neonatal morbidity, the same increased risk of SGA and LGA were observed following fresh embryo transfer or IUI and FET (aOR 1.23 [1.19-1.27] or 1.06 [1.01-1.11] and aOR 1.36 [1.30-1.43], respectively).

CONCLUSIONS

An effect of MAR techniques on the risks for SGA and LGA is suggested independently from maternal context and obstetrical or neonatal morbidities. Pathophysiological mechanisms remain poorly understood and should be further evaluated, as well as the influence of embryonic stage and freezing techniques.

Offspring physiology following the use of IVM, IVF and ICSI: a systematic review and meta-analysis of animal studies

BACKGROUND

Since the birth of the first baby using IVF technology in 1978, over 10 million children have been conceived via ART. Although most aspects of ARTs were developed in animal models, the introduction of these technologies into clinical practice was performed without comprehensive assessment of their long-term safety. The monitoring of these technologies over time has revealed differences in the physiology of babies produced using ARTs, yet due to the pathology of those presenting for treatment, it is challenging to separate the cause of infertility from the effect of treatments offered. The use of systematic review and meta-analysis to investigate the impacts of the predominant ART interventions used clinically in human populations on animals produced in healthy fertile populations offers an alternative approach to understanding the long-term safety of reproductive technologies.

OBJECTIVE AND RATIONALE

This systematic review and meta-analysis aimed to examine the evidence available from animal studies on physiological outcomes in the offspring conceived after IVF, IVM or ICSI, compared to in vivo fertilization, and to provide an overview on the landscape of research in this area.

SEARCH METHODS

PubMed, Embase and Commonwealth Agricultural Bureaux (CAB) Abstracts were searched for relevant studies published until 27 August 2021. Search terms relating to assisted reproductive technology, postnatal outcomes and mammalian animal models were used. Studies that compared postnatal outcomes between in vitro-conceived (IVF, ICSI or IVM) and in vivo-conceived mammalian animal models were included. In vivo conception included mating, artificial insemination, or either of these followed by embryo transfer to a recipient animal with or without in vitro culture. Outcomes included birth weight, gestation length, cardiovascular, metabolic and behavioural characteristics and lifespan.

OUTCOMES

A total of 61 studies in five different species (bovine, equine, murine, ovine and non-human primate) met the inclusion criteria. The bovine model was the most frequently used in IVM studies (32/40), while the murine model was mostly used in IVF (17/20) and ICSI (6/8) investigations. Despite considerable heterogeneity, these studies suggest that the use of IVF or maturation results in offspring with higher birthweights and a longer length of gestation, with most of this evidence coming from studies in cattle. These techniques may also impair glucose and lipid metabolism in male mice. The findings on cardiovascular outcomes and behaviour outcomes were inconsistent across studies.

WIDER IMPLICATIONS

Conception via in vitro or in vivo means appears to have an influence on measurable outcomes of offspring physiology, manifesting differently across the species studied. Importantly, it can be noted that these measurable differences are noticeable in healthy, fertile animal populations. Thus, common ART interventions may have long-term consequences for those conceived through these techniques, regardless of the pathology underpinning diagnosed infertility. However, due to heterogeneous methods, results and measured outcomes, highlighted in this review, it is difficult to draw firm conclusions. Optimizing animal and human studies that investigate the safety of new reproductive technologies will provide insight into safeguarding the introduction of novel interventions into the clinical setting. Cautiously prescribing the use of ARTs clinically may also be considered to reduce the chance of promoting adverse outcomes in children conceived before long-term safety is confidently documented.

Serum anti-Müllerian hormone levels are associated with perinatal outcomes in women undergoing IVF/ICSI: A multicenter retrospective cohort study

INTRODUCTION

Anti-Müllerian hormone (AMH) level has long been considered as a serum biomarker of ovarian reserve clinically, while emerging data suggest that serum AMH level may also predict pregnancy outcomes. However, whether pregestational serum AMH levels are related to perinatal outcomes among women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles is unknown.

OBJECTIVE

To explore the association between different AMH levels and perinatal outcomes in women with live births in IVF/ICSI.

METHODS

This multicenter retrospective cohort study was conducted among three different provinces in China, from January 2014 to October 2019. A total of 13,763 IVF/ICSI cycles with 5657 live-delivery pregnant women and 6797 newborns were recruited. Participants were categorized into three groups according to the <25th (low), 25 to 75th (average), and >75th (high) percentile of serum AMH concentration. Perinatal outcomes were compared among groups. Subgroup analyses were conducted based on the number of live births.

RESULTS

Among women with singleton deliveries, low and high AMH levels increased the risk of intrahepatic cholestasis of pregnancy (ICP) (aOR1 = 6.02, 95%CI: 2.10-17.22; aOR2 = 3.65, 95%CI:1.32-10.08) and decreased the risk of macrosomia (aOR1 = 0.65, 95%CI:0.48-0.89; aOR2 = 0.72, 95%CI:0.57-0.96), while low AMH reduced the risk of large for gestational age (LGA, aOR=0.74, 95%CI:0.59-0.93) and premature rupture of membrane (PROM, aOR=0.50, 95%CI:0.31-0.79)compared with the average AMH group. In women with multiple deliveries, high AMH levels increased the risks of gestational diabetes mellitus (GDM, aOR=2.40, 95%CI:1.48-3.91) and pregnancy-induced hypertension (PIH, aOR=2.26, 95%CI:1.20-4.22) compared with the average AMH group, while low AMH levels increased the risk of ICP (aOR=14.83, 95%CI:1.92-54.30). However, there was no evidence of differences in preterm birth, congenital anomaly, and other perinatal outcomes among the three groups in both singleton and multiple deliveries.

CONCLUSIONS

Abnormal AMH levels increased the risk of ICP regardless of the number of live births for women undergoing IVF/ICSI, while high AMH levels increased the risks of GDM and PIH in multiple deliveries. However, serum AMH levels were not associated with adverse neonatal outcomes in IVF/ICSI. The underlying mechanism warrants further investigation.

School-age outcomes among IVF-conceived children: A population-wide cohort study

BACKGROUND

In vitro fertilisation (IVF) is a common mode of conception. Understanding the long-term implications for these children is important. The aim of this study was to determine the causal effect of IVF conception on primary school-age childhood developmental and educational outcomes, compared with outcomes following spontaneous conception.

METHODS AND FINDINGS

Causal inference methods were used to analyse observational data in a way that emulates a target randomised clinical trial. The study cohort comprised statewide linked maternal and childhood administrative data. Participants included singleton infants conceived spontaneously or via IVF, born in Victoria, Australia between 2005 and 2014 and who had school-age developmental and educational outcomes assessed. The exposure examined was conception via IVF, with spontaneous conception the control condition. Two outcome measures were assessed. The first, childhood developmental vulnerability at school entry (age 4 to 6), was assessed using the Australian Early Developmental Census (AEDC) (n = 173,200) and defined as scoring <10th percentile in ≥2/5 developmental domains (physical health and wellbeing, social competence, emotional maturity, language and cognitive skills, communication skills, and general knowledge). The second, educational outcome at age 7 to 9, was assessed using National Assessment Program-Literacy and Numeracy (NAPLAN) data (n = 342,311) and defined by overall z-score across 5 domains (grammar and punctuation, reading, writing, spelling, and numeracy). Inverse probability weighting with regression adjustment was used to estimate population average causal effects. The study included 412,713 children across the 2 outcome cohorts. Linked records were available for 4,697 IVF-conceived cases and 168,503 controls for AEDC, and 8,976 cases and 333,335 controls for NAPLAN. There was no causal effect of IVF-conception on the risk of developmental vulnerability at school-entry compared with spontaneously conceived children (AEDC metrics), with an adjusted risk difference of -0.3% (95% CI -3.7% to 3.1%) and an adjusted risk ratio of 0.97 (95% CI 0.77 to 1.25). At age 7 to 9 years, there was no causal effect of IVF-conception on the NAPLAN overall z-score, with an adjusted mean difference of 0.030 (95% CI -0.018 to 0.077) between IVF- and spontaneously conceived children. The models were adjusted for sex at birth, age at assessment, language background other than English, socioeconomic status, maternal age, parity, and education. Study limitations included the use of observational data, the potential for unmeasured confounding, the presence of missing data, and the necessary restriction of the cohort to children attending school.

CONCLUSIONS

In this analysis, under the given causal assumptions, the school-age developmental and educational outcomes for children conceived by IVF are equivalent to those of spontaneously conceived children. These findings provide important reassurance for current and prospective parents and for clinicians.

General health in a cohort of children conceived after assisted reproductive technology in the United Kingdom: a population-based record-linkage study

BACKGROUND

Assisted reproductive technology use is increasing annually; however, data on long-term child health outcomes including hospital admissions are limited.

OBJECTIVE

This study aimed to examine the potential effects of assisted reproductive technology on any and cause-specific hospital admissions unrelated to perinatal diagnoses.

STUDY DESIGN

This was a population-based record-linkage study that included a previously established cohort of children born after assisted reproductive technology in the United Kingdom between 1997 and 2009 (n=63,877), their naturally conceived siblings (n=11,343), and matched naturally conceived population controls (n=127,544) linked to their postnatal health outcomes up to March 31, 2016 to provide robust risk estimates of the potential effects of assisted reproductive technology on any and cause-specific hospital admissions unrelated to perinatal diagnoses. In addition, comparison of hospital admissions by type of treatment was made. Cox regression was used to estimate the risk of hospital admission, and negative binomial regression was used to compare the number of hospital admissions per year.

RESULTS

This study had 1.6 million person-years of follow-up (mean, 12.9 years; range, 0-19 years), and the mean age at the time of first hospital admission was 6.5 years (range, 0-19 years). Singletons born after assisted reproductive technology had increased risk of any hospital admission compared with naturally conceived population controls (hazard ratio, 1.08; 95% confidence interval, 1.05-1.10) but not naturally conceived siblings (hazard ratio, 1.01; 95% confidence interval, 0.94-1.09). We observed increased risk of diagnoses related to neoplasms and diseases of the respiratory, musculoskeletal, digestive, and genitourinary systems, and lower risk of injury, poisoning, and consequences of external causes compared with naturally conceived population controls. Children born after intracytoplasmic sperm injection had a lower risk of hospital admission compared with those born after in vitro fertilization, although no such differences were observed between children born after fresh embryo transfers and those born after frozen embryo transfers.

CONCLUSION

Children born after assisted reproductive technology had greater numbers of hospital admissions compared with naturally conceived population controls. Attenuation of these differences in relation to their naturally conceived siblings suggested that this could be partially attributed to the influence of parental subfertility on child health, increased parental concerns, and an actual increase in morbidity in children born after assisted conception.

Assisted reproductive technology and neonatal intensive care unit: A retrospective observational study from a single center

BACKGROUND

An increasing number of infants are being conceived using assisted reproductive technology (ART). The effects of infertility treatments (IFTs) on infant outcomes have been extensively debated; however, a consensus has not yet been reached. In the present study, we investigated the impact of IFTs on neonatal intensive care unit (NICU) managements using data collected at a single large NICU center.

METHODS

We retrospectively investigated patients admitted to the University of Tokyo Hospital NICU during three different time periods (2010, 2015, and 2020). We included 131, 201, and 323 infants, respectively, and compared a number of factors among groups classified by the mode of conception: spontaneous pregnancy (SP), non-ART (conceived with assisted ovulation or artificial insemination), and ART. We also compared the mode of conception among inborn singletons.

RESULTS

The rate of admission of ART infants significantly increased from 2010 (9.1%) to 2015 (22.9%) and 2020 (25.7%) (p values of <0.05 and <0.01, respectively). When compared among inborn singletons, ART infants were more often admitted to NICU (p < 0.01). Congenital anomalies and surgical interventions were significantly more frequent in the SP group than in the ART group (p < 0.01). No significant differences were observed in neonatal outcomes among ART infants from 2010 to 2015/2020.

CONCLUSIONS

The rate of ART infants admitted to the NICU has significantly increased, with ART pregnancies now accounting for 25% of admissions to the perinatal medical center. ART procedure may be a risk factor for NICU admission. Neonatal intensive care is becoming increasingly indispensable for ART pregnancies.

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.

Obstetric and Perinatal Outcomes of Singleton Births Following Single- vs Double-Embryo Transfer in Sweden

Importance

Pregnancies resulting from assisted reproductive technology are associated with an increased risk of adverse perinatal outcomes compared with those following natural conception. Previous studies have shown an association of pregnancies resulting from transfer of multiple embryos with these negative findings.

Objective

To determine the risk for adverse outcomes in singletons conceived through assisted reproduction using double-embryo transfer (DET) vs single-embryo transfer (SET).

Design, Setting, and Participants

This cohort study used data from women who achieved singleton deliveries after SET or DET in Sweden between 2007 and 2017 as recorded in the National Quality Registry for Assisted Reproduction. All embryo transfers, at cleavage or blastocyst stage, replaced in fresh or frozen treatment cycles were included. Data on obstetric and neonatal outcomes were retrieved by linkage to the National Medical Birth Register. Naturally conceived singletons were included as a reference group. Data were analyzed between September 2021 and August 2022.

Exposures

Double-embryo transfer leading to singleton birth.

Main Outcomes and Measures

Relative risk ratios or odds ratios (ORs) and absolute risk differences (ARDs) in percentage points with 95% CIs were calculated for obstetric and perinatal outcomes in singleton births conceived using DET vs SET.

Results

Among 1 115 863 singleton births, 30 713 singletons were born after SET and 5123 after DET. A higher risk of neonatal death was found in singletons after DET vs SET (OR, 2.67 [95% CI, 1.28-5.55]; ARD, 0.2 percentage points [95% CI, 0.0-0.4 percentage points]). In frozen embryo transfers, DET was associated with a higher risk of low birth weight (OR, 1.64 [95% CI, 1.19-2.25]; ARD, 2.0 percentage points [95% CI, 0.5-3.5 percentage points]). Among blastocyst transfers, DET was associated with very preterm birth (relative risk ratio, 2.64 [95% CI, 1.50-4.63]; ARD, 1.8 percentage points [95% CI, 0.3-3.4 percentage points]) and low birth weight (OR, 1.83 [95% CI, 1.29-2.60]; ARD, 3.2 percentage points [95% CI, 0.9-5.5 percentage points]).

Conclusions and Relevance

These results indicate a higher risk of adverse outcomes following DET, even when the result is a singleton birth, vs singletons born after SET. Adverse outcomes were mainly observed in singletons following DET using frozen embryos and blastocysts.

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.

Perinatal outcomes of 221,709 singleton and twin pregnancies after the use of donor versus partner sperm

OBJECTIVE

To study the association of donor sperm on perinatal outcomes of livebirths conceived via in vitro fertilization (IVF) when compared with partner sperm.

DESIGN

Retrospective cohort study SETTING: National Human Fertilisation and Embryology Authority assisted reproductive technology registry PATIENTS: All live born singletons and twins conceived through IVF with or without intracytoplasmic sperm injection in the United Kingdom between 1991 and 2016 INTERVENTION(S): Donor sperm compared to partner sperm MAIN OUTCOME MEASURE(S): Perinatal outcomes were assessed. The primary outcomes were preterm and very preterm birth; low, very low, high, and very high birthweight; Secondary outcomes were congenital anomaly and health baby. These were assessed for singletons and twins separately.

RESULTS

For singleton livebirths, compared to partner sperm, those conceived with donor sperm were at reduced odds of very preterm (odds ratio [OR], 0.76; 95% confidence interval [CI], 0.63-0.91; adjusted OR [aOR], 0.80; 95% CI, 0.66-0.96), and preterm (OR, 0.90; 95% CI, 0.83-0.98; aOR, 0.93; 95% CI, 0.85-1.01) birth. For birthweight outcomes, donor sperm showed a reduced odds of low (OR, 0.83; 95% CI, 0.76-0.91; aOR, 0.86; 95% CI, 0.78-0.94) and an increased odds of high (OR, 1.15; 95% CI, 1.07-1.23; aOR, 1.09; 95% CI, 1.01-1.17) birthweight. There was no confirmed difference in the odds ratios of very low (OR, 0.88; 95% CI, 0.74-1.06; aOR, 0.94; 95% CI, 0.78-1.13) or very high (OR, 1.21; 95% CI, 1.04-1.40; aOR, 1.15; 95% CI, 0.98-1.34) birthweight. Liveborn twins conceived with donor sperm, compared to partner sperm, were at reduced odds of very low (OR, 0.76; 95% CI, 0.66-0.88; aOR, 0.83; 95% CI, 0.72-0.96) and low (OR, 0.87; 95% CI, 0.81-0.93; aOR, 0.91; 95% CI, 0.85-0.98) birthweight. There was a suggestion of a reduced odds of very preterm (OR, 0.81; 95% CI, 0.70-0.95; aOR, 0.86; 95% CI, 0.74-1.01) and preterm (OR, 0.93; 95% CI, 0.86-1.01; aOR, 0.96; 95% CI, 0.88-1.04) birth. There was considerable uncertainty around the ORs for high (OR, 0.73; 95% CI, 0.31-1.72; aOR, 0.72; 95% CI, 0.29-1.80) and very high (OR, 1.02; 95% CI, 0.39-2.67; aOR, 1.34; 95% CI, 0.50-3.60) birthweight.

CONCLUSION

Although unmeasured confounding remains a possibility, as paternal age, body mass index, and smoking status were unavailable for analysis, women, couples, service providers can be reassured that IVF livebirths conceived with donor sperm have no greater chance of adverse outcomes when compared to partner sperm.

Assisted Reproductive Technology and Natural Law: How Seven Years as an Embryologist Revealed IVF's Disordered Approach to Patient Care

This article is a case study illuminating the experience of a cradle Catholic who pursued a career in the field of Assisted Reproductive Technology (ART) as a laboratory director and embryologist. Twenty years after leaving the field, the observations leading to the crisis of conscience are further amplified by the reports of social, legal, ethical, and medical consequences of the technology. These consequences are explored in detail and can serve as a mini-review of the published scientific literature describing the obstetrical complications, peri-natal outcomes, and the long-term health effects on the offspring. This paper provides the documented evidence that can be used by the religious and medical community for shepherding the flock. The disordered approach to patient care is evidenced by five serious consequences resulting from the use of the technology. These include multiple pregnancy and selective reduction, abandoned and discarded embryos, adverse health effects to the women and children, legal and ethical problems, and human experimentation. An explanation for the adverse consequences can be found by exploring and applying the principles of Natural Law. Natural Law, as embraced by the Catholic Church, can be used as a starting point for conversion of heart for many who struggle with the immorality of ART. Deterring use of the technology coupled with increased motivation by scientist and health professionals to pursue restorative approaches within a moral framework offer our best solution to the treatment of infertility. Natural Law and the consequences of violating it provide evidence that science and medicine should not be practiced in a vacuum void of ethical and moral boundaries grounded in divine Wisdom.

Should we adopt a prognosis-based approach to unexplained infertility?

The treatment of unexplained infertility is a contentious topic that continues to attract a great deal of interest amongst clinicians, patients and policy makers. The inability to identify an underlying pathology makes it difficult to devise effective treatments for this condition. Couples with unexplained infertility can conceive on their own and any proposed intervention needs to offer a better chance of having a baby. Over the years, several prognostic and prediction models based on routinely collected clinical data have been developed, but these are not widely used by clinicians and patients. In this opinion paper, we propose a prognosis-based approach such that a decision to access treatment is based on the estimated chances of natural and treatment-related conception, which, in the same couple, can change over time. This approach avoids treating all couples as a homogeneous group and minimizes unnecessary treatment whilst ensuring access to those who need it early.

Effects of assisted reproductive technology on severe maternal morbidity risk in both singleton and multiple births in Korea: A nationwide population-based cohort study

BACKGROUND

Whether infertility treatment predicts severe maternal morbidity in both singleton and twin pregnancies is controversial. We conducted this nationwide population-based cohort study to compare pregnancies conceived through assisted reproductive technology treatments, such as intrauterine insemination or in vitro fertilization, with unassisted pregnancies.

METHODS

This study included 269,930 women who experienced childbirth in 2018, using data of the National Health Insurance Service National Delivery Cohort in Korea. The primary outcome was assessed using a severe maternal morbidity algorithm developed by the Centers for Disease Control and Prevention in the United States. A modified Poisson regression was used to estimate the adjusted risk ratio of severe maternal morbidity.

RESULTS

Severe maternal morbidity occurred in 6,333 (2.3%) of 280,612 deliveries investigated. The risk of severe maternal morbidity was approximately 1.5-fold higher among women who received in vitro fertilization (risk ratio: 1.51, 95% confidence interval: 1.36-1.68) than among fertile women. However, no significant association between intrauterine insemination and maternal morbidity was identified. Via subgroup analysis, in vitro fertilization increased the risk of severe maternal morbidity by 1.6- and 1.3-fold in singleton and multiple births, respectively (singleton: risk ratio: 1.62, 95% confidence interval: 1.43-1.83; multiple birth: risk ratio: 1.31, 95% confidence interval: 1.07-1.60).

CONCLUSIONS

This study suggested that in vitro fertilization was associated with the risk of severe maternal morbidity in both singleton and multiple births. Further research should identify patient- and treatment-specific factors that may mitigate or prevent adverse maternal health risks.

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.

Clomifene and Assisted Reproductive Technology in Humans Are Associated with Sex-Specific Offspring Epigenetic Alterations in Imprinted Control Regions

Children conceived with assisted reproductive technology (ART) have an increased risk of adverse outcomes, including congenital malformations and imprinted gene disorders. In a retrospective North Carolina-based-birth-cohort, we examined the effect of ovulation drugs and ART on CpG methylation in differentially methylated CpGs in known imprint control regions (ICRs). Nine ICRs containing 48 CpGs were assessed for methylation status by pyrosequencing in mixed leukocytes from cord blood. After restricting to non-smoking, college-educated participants who agreed to follow-up, ART-exposed (n = 27), clomifene-only-exposed (n = 22), and non-exposed (n = 516) groups were defined. Associations of clomifene and ART with ICR CpG methylation were assessed with linear regression and stratifying by offspring sex. In males, ART was associated with hypomethylation of the PEG3 ICR [β(95% CI) = -1.46 (-2.81, -0.12)] and hypermethylation of the MEG3 ICR [3.71 (0.01, 7.40)]; clomifene-only was associated with hypomethylation of the NNAT ICR [-5.25 (-10.12, -0.38)]. In female offspring, ART was associated with hypomethylation of the IGF2 ICR [-3.67 (-6.79, -0.55)]. Aberrant methylation of these ICRs has been associated with cardiovascular disease and metabolic and behavioral outcomes in children. The results suggest that the increased risk of adverse outcomes in offspring conceived through ART may be due in part to altered methylation of ICRs. Larger studies utilizing epigenome-wide interrogation are warranted.

The changing impact of assisted reproductive techniques on preterm birth during the period 2007-2020 in Lombardy, Northern Italy

OBJECTIVE

To assess the impact of Assisted Reproductive Techniques (ART) on the risk of preterm birth (PTB).

STUDY DESIGN

This retrospective population-based study used healthcare utilization databases of the Lombardy Region to select all the deliveries occurred between 2007 and 2020. Log-binomial regression models were fitted to estimate prevalence ratio (PR) and the corresponding 95% confidence interval (CI) of PTB among deliveries after ART. Estimates were adjusted for maternal sociodemographic features. Furthermore, the population attributable fraction was computed. All the analyses were performed for calendar period and were repeated excluding multiple births.

RESULTS

In our cohort, an increasing trend in the number of ART emerged, with an overall rate of 25.8 per 1,000 deliveries (N = 28,742). ART was positively related to PTB (aPR = 2.83, 95 % CI: 2.76-2.91) with a downward trend. Over the period study, multiple births after ART decreased (from 20.4 % to 8.4 %) and were constantly burdened by a higher number of PTB. Excluding multiple births, the association was substantially lower (aPR = 1.72, 95 % CI: 1.65-1.79) and did not describe any trend. Moreover, stratifying for type of pregnancy, the association was observed only among singletons. Finally, the proportion of PTB considered attributable to ART increased from about 2-3 % to 6 % till the 2016, then decreased.

CONCLUSION

The investigation suggested that ART was related to PTB; this association may be partly justified by the high rate of multiple births among women who conceived non spontaneously. However, excluding multiple births, ART remained associated with PTB.

The effect of interpregnancy interval on preterm birth and low birth weight in singleton pregnancies conceived without assistance or by infertility treatments

OBJECTIVE

To determine the association of interpregnancy interval on perinatal outcomes and whether this was influenced by mode of conception.

DESIGN

Retrospective cohort.

SETTING

Centers for Disease Control and Prevention's natality national database.

PATIENT(S)

Patients who had an index singleton live birth with a preceding live birth. Index pregnancies from 2016 to 2019 were conceived with in vitro fertilization (IVF) (n = 32,829) or ovulation induction/intrauterine insemination (OI/IUI) (n = 23,016) or without assistance (n = 7,564,042).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary outcomes evaluated were preterm birth (<37 weeks) and low birth weight (<2,500 g). Multivariable logistic regression was performed to evaluate the association of interpregnancy intervals with perinatal outcomes stratified by mode of conception. Adjusted odds ratios and 95% confidence intervals (CIs) were presented.

RESULT(S)

Compared with the interpregnancy interval reference group of 12 to <18 months, a <12 month interpregnancy interval was associated with an increase in preterm birth (<37 weeks) for pregnancies conceived with OI/IUI or without assistance (aOR, 1.42; 95% CI, 1.16-1.74, and aOR, 1.14; 95% CI, 1.13-1.15, respectively), whereas IVF was not associated with an increase (aOR, 0.90; 95% CI, 0.77-1.04). A <12 month interpregnancy interval was associated with an increase in low birth weight for pregnancies conceived with IVF or OI/IUI or without assistance (aOR, 1.34; 95% CI, 1.09-1.64; aOR, 1.33; 95% CI, 1.01-1.76; and aOR, 1.26; 95% CI, 1.24-1.27, respectively).

CONCLUSION(S)

An interpregnancy interval of at least 12 months reduces adverse perinatal outcomes for pregnancies conceived with and without infertility treatment.

Is telephone follow-up reliable in maternal and neonatal outcomes surveys in in vitro fertilization?

BACKGROUND

 Many studies that collect maternal and neonatal outcomes rely on patient self-report phone calls. It is unclear how reliable or accurate these phone call reports are.

OBJECTIVE

To evaluate the reliability of telephone calls in information collection in IVF.

STUDY DESIGN

The women were interviewed seven days after delivery by a nurse via telephone. The maternal and neonatal outcomes were recorded based on a self-report from one of the spouses. Meanwhile, the standardized electronic hospitalized discharge records were extracted from the hospital medical database. For each case, maternal and neonatal information obtained from telephone interviews and extracted from medical files were compared.

RESULTS

Agreement was classified as "almost perfect, K = 0.81-1.00" for preterm birth, cesarean delivery, low birth weight baby, and macrosomia. The strength of agreement was classified as "moderate, K = 0.41-0.60" for some antepartum complications: gestational diabetes (K = 0.569); pregnancy-induced hypertension (K = 0.588); intrahepatic cholestasis of pregnancy (K = 0.597) and oligohydramnios (K = 0.432). The strength of agreement between telephone interviews and hospitalized discharge records can be classified as "slight (K = 0-0.20)" for some complications: thyroid diseases (K = 0.137), anemia (K = 0.047), postpartum hemorrhage (K = 0.016), and Fetal distress (K = 0.106).

CONCLUSION

Some variables (preterm birth, cesarean delivery, birth weight) information collected by telephone follow-up were reliable. However, other complications (thyroid diseases, anemia, postpartum hemorrhage, and fetal distress) collected via self-report was non-reliable. Compared with complications during labor, antepartum complications have higher agreement between different follow-up methods. IVF records and hospitalized discharge records should be matched and collected simultaneously when discussing maternal and neonatal outcomes of IVF.

Microsurgical Management of Male Infertility: Compelling Evidence That Collaboration with Qualified Male Reproductive Urologists Enhances Assisted Reproductive Technology (ART) Outcomes

A male factor plays a significant role in a couple's reproductive success. Today, advances in reproductive technology, such as intracytoplasmic sperm injection (ICSI), have allowed it to be possible for just a single sperm to fertilize an egg, thus, overcoming many of the traditional barriers to male fertility, such as a low sperm count, impaired motility, and abnormal morphology. Given these advances in reproductive technology, it has been questioned whether a reproductive urologist is needed for the evaluation and treatment of infertile and subfertile men. In this review, we aim to provide compelling evidence that collaboration between reproductive endocrinologists and reproductive urologists is essential for optimizing a couple's fertility outcomes, as well as for improving the health of infertile men and providing cost-effective care.

Investigating of the effects of trophectoderm morphology on obstetrics outcome in 5th day blastocyst transfer in patients with in vitro fertilization

Objective:

Trophectoderm (TE) cells are the first differentiating cells in embryo development and have epithelial features. TE cells, which associate with implantation of the blastocyst into the uterine endometrium, contribute to the formation of the placenta. Inner cells mass (ICM) together with TE cells are used for determining embryo quality. The aim of this study was to investigate the role of TE and ICM cells on pregnancy outcome in 5^th day blastocyst transferred in-vitro-fertilization (IVF) pregnancy.

Material and Methods:

This was a retrospective study using data from all patients who applied for blastocyst transfer IVF between January 2015 and March 2019 at the Reproductive Endocrinology and Infertility Center of Akdeniz University Faculty of Medicine, Department of Obstetrics and Gynecology. ALPHA İstanbul consensus evaluation system was used for grading of the blastocyst. The embryo quality, expansion, ICM and TE morphology of the 5^th day transferred blastocyst was assessed, together with abortion rate, live birth rate, pregnancy complications, and pregnancy outcomes.

Results:

There was a significantly increased risk of preeclampsia (PE) (7.8% vs 1.1%; p=0.041), preterm delivery (PD) (36% vs 17.7%; p=0.037), and antenatal bleeding rates (13.6% vs 5%; p=0.021) in TE-C compared to the TE-A + TE-B blastocysts. Furthermore, a higher rate of obstetric complications was observed in ICM-C compared to ICM-A and B (p=0.003). There was a significant correlation between TE morphology and implantation success, ongoing pregnancy rate, and abortion incidence.

Conclusion:

These results suggest that TE cell morphology is related to implantation success and pregnancy outcomes, especially in terms of the risk of abortion, PE, PD, and antenatal bleeding. It may be advisable to counsel women concerning possible poor obstetric outcome due to poor ICM quality. Future prospective and controlled studies are needed to clarify this association.

Greater estimated fetal weight and birth weight in IVF/ICSI pregnancy after frozen-thawed vs fresh blastocyst transfer: prospective cohort study with novel unified modeling methodology

OBJECTIVE

To compare, using a unified approach, standardized estimated fetal weight (EFW) trajectories from the second trimester to birth and birth-weight (BW) measurements in in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) pregnancies obtained after frozen-thawed vs fresh blastocyst transfer (BT).

METHODS

This was a secondary analysis of a prospective longitudinal cohort study performed at the Fetal Medicine and Obstetric Departments of San Raffaele Hospital in Milan, Italy, from January 2016 to December 2020. Eligible for inclusion were singleton viable gestations conceived by autologous IVF/ICSI conception after fresh or frozen-thawed BT that underwent standard fetal biometry assessment at 19-41 weeks and had BW measurements available. All ultrasound assessments were performed by operators blinded to the employment of cryopreservation. Patients with twin gestation, significant pregestational disease, miscarriage, major fetal abnormalities and use of other types of medically assisted reproduction techniques were excluded. EFW and BW Z-scores and their trajectories were analyzed using general linear models (GLM) and logistic regression with a unified modeling methodology based on the Fetal Medicine Foundation fetal and neonatal population weight charts, adjusting for major confounders. Differences between prenatal EFW and postnatal BW centiles in the two groups were assessed and compared using contingency tables, χ² test and conversion of prenatal to postnatal centiles.

RESULTS

A total of 631 IVF/ICSI pregnancies were considered, comprising 263 conceived following fresh BT and 368 after frozen-thawed BT. A total of 1795 EFW observations were available (n = 715 in fresh BT group and n = 1080 in frozen-thawed BT group; median of three observations per patient). EFW and BW < 10^th centile were significantly more frequent in the fresh than in the frozen-thawed BT group (P = 0.003 and P < 0.001, respectively). EFW and BW > 90^th centile were significantly more frequent in the frozen-thawed vs fresh BT group (P = 0.034 and P = 0.002, respectively). GLM showed significantly decreasing EFW Z-scores with advancing gestational age (GA) in both groups. The effect of GA was assumed to be equal in the two study groups, as no significant interaction effect was found. Smoothed mean EFW Z-scores from 19 weeks of gestation to term and smoothed mean BW Z-scores were both significantly higher in the frozen-thawed compared with the fresh BT group (EFW Z-score, 0.70 ± 1.29 vs 0.28 ± 1.43; P < 0.001; BW Z-score, 0.04 ± 1.08 vs -0.31 ± 1.28; P < 0.001). Mean smoothed EFW Z-score values in the frozen-thawed vs fresh BT groups were 1.01 ± 0.12 vs 0.60 ± 0.08 at 19-27 weeks, 0.36 ± 0.07 vs -0.06 ± 0.04 at 28-35 weeks and -0.66 ± 0.01 vs -0.88 ± 0.02 at 36-41 weeks. Mean smoothed BW Z-score values in the frozen-thawed vs fresh BT groups were -0.80 ± 0.14 vs -1.20 ± 0.10 at 28-35 weeks and 0.22 ± 0.16 vs -0.24 ± 0.14 at 36-41 weeks. Assessment of EFW and BW concordance showed a significantly greater rate of postnatal confirmation of prenatally predicted small-for-gestational age (SGA) < 10^th centile in the fresh compared with the frozen-thawed BT group (P < 0.001), whereas the rate of postnatal confirmation of large-for-gestational age (LGA) > 90^th centile was significantly higher in the frozen-thawed vs the fresh BT group (P < 0.001). Logistic regression analysis showed that the smoothed rate of EFW < 3^rd centile was about 6-fold higher in the fresh vs frozen-thawed BT group (P < 0.001), whereas the smoothed rates of EFW 90^th -97^th centile and > 97^th centile were nearly double in the frozen-thawed compared with the fresh BT group (P < 0.05 and P < 0.001, respectively).

CONCLUSIONS

Robust novel unified prenatal-postnatal modeling in IVF/ICSI pregnancies after frozen-thawed or fresh BT from 19 weeks of gestation to birth showed non-divergent growth trajectories, with higher EFW and BW Z-scores in the frozen-thawed vs fresh BT group. The mean EFW Z-scores in both IVF/ICSI groups were greater than those expected for natural conceptions, being highest in the midtrimester and decreasing with advancing gestation in both groups, becoming negative after 32 weeks in the fresh and after 35 weeks in the frozen-thawed BT group. Mean BW Z-scores were negative in both groups, with lower values in preterm fetuses, and increased with advancing gestation, becoming positive at term in the frozen-thawed BT group. IVF/ICSI conceptions from frozen-thawed as compared to fresh BT presented increased rate of LGA and reduced rate of SGA both prenatally and postnatally. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Systemic vascular resistance may influence the outcome of in vitro fertilization

Introduction: The number of pregnancies obtained through in vitro fertilization (IVF) techniques are increasing, and only few studies have investigated hemodynamic variations in women undergoing IVF techniques. The aim of this study was to evaluate the hemodynamic parameters in women undergoing IVF, to assess a possible correlation between hemodynamics and embryo implantation.Methods: 45 normotensive non-obese women, age ≤ 43 years, with idiopathic or tubal infertility, referred to the Reproductive Physiopathology and Andrology Unit, Sandro Pertini Hospital, Rome, during the period 2020/2021, underwent IVF techniques. All women were evaluated with Ultra Sonic Cardiac Output Monitor (USCOM) to detect hemodynamic parameters at two different stages: at the mid-luteal phase, before the beginning of IVF, and at the day of embryo transfer (dET). All demographics and hormonal parameters in both groups were comparable. The hemodynamic parameters were compared between women with a positive β-HCG test vs. those testing negative.Results: 11 out of 45 (24,5%) women obtained positive β-HCG test. All demographics and hormonal parameters were comparable in both groups. Women with a positive β-HCG test showed statistically lower systemic vascular resistance (SVR) at mid-luteal phase (868.61 ± 100.1 vs. 1009 ± 168.4) and dET (818,9 ± 104.5 vs 1038.52 ± 150.82 dynes × s/cm⁵).Conclusions: Hemodynamic assessment can identify a more favorable pre-pregnancy cardiovascular adaptation. Embryo implantation might be positively influenced by the hemodynamic parameters, e.g. lower SVR, before the beginning of IVF techniques, and during the window of implantation.

Pregnancy complications and placental histology following embryo transfer with a thinner endometrium

STUDY QUESTION

Are deliveries following IVF with a thinner endometrium associated with adverse perinatal outcomes and placental findings?

SUMMARY ANSWER

Live births following IVF with a thinner endometrium are associated with an increased rate of placental-mediated obstetric complications and lower birthweight, while the placentas are notable for gross anatomical and histological malperfusion lesions.

WHAT IS KNOWN ALREADY

Past studies have noted a higher rate of adverse outcomes on deliveries following IVF with a thinner endometrium, mainly placental-associated complications. However, no study to date has investigated placental histopathology in such cases.

STUDY DESIGN, SIZE, DURATION

This was a retrospective cohort study of 1057 deliveries following IVF, between 2009 and 2017. All placentas were sent to pathology irrelevant of pregnancy complication status, per protocol at our institution.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Live singleton births from a tertiary university hospital after IVF were compared between patients for whom embryo transfer was performed with an endometrium <9 mm (thinner endometrium group) and patients with an endometrium ≥9 mm (control group). Placental pathologic findings were categorized according to the Amsterdam Placental Workshop Group Consensus. Outcomes were placental findings, including anatomic, inflammatory, vascular malperfusion and villous maturation lesions, as well as obstetric and perinatal outcomes. Continuous and categorical variables were compared as appropriate, and multivariate regression and linear analyses were employed to control for confounders.

MAIN RESULTS AND THE ROLE OF CHANCE

A total 292 cases in the thinner endometrium group, and 765 in the control group were compared. Maternal demographics were non-significant between the groups, except for main fertility indication was more commonly diminished reserve in patients with a thinner endometrium and less commonly male factor, P = 0.003. Higher rates of fresh transfers were noted in the control group, while the thinner endometrium group was notable for higher rates of blastocyte transfers. After adjustment for confounders, deliveries in the thinner endometrium group were associated with an overall higher rate of main placental-mediated complications, 22.9% versus 15.2%, P = 0.003, and significantly lower birthweight, β -100.76 g (-184.4-(-17.0)). Placentas in the thinner endometrium group were notable for reduced thickness and a higher rate of bilobated placentas. Placental histology in the thinner endometrium group demonstrated a higher rate of maternal malperfusion lesions.

LIMITATIONS, REASONS FOR CAUTION

The study was limited by its retrospective design and lack of data regarding prior uterine surgery. In addition, sample size was limited for detection of differences in outcomes of rarer occurrence and for analysis as per a stricter definition of thin endometrium.

WIDER IMPLICATIONS OF THE FINDINGS

Excess obstetric risks should be taken into consideration while planning an embryo transfer with a thinner endometrium. Further studies are needed to assess the yield of cycle cancellation and the effect of potential preventive measures such as Micropirin treatment.

STUDY FUNDING/COMPETING INTEREST(S)

No funding was used and the authors report no conflicting interests.

TRIAL REGISTRATION NUMBER

N/A.

The Consequences of Assisted Reproduction Technologies on the Offspring Health Throughout Life: A Placental Contribution

The use of assisted reproductive technologies (ART) worldwide has led to the conception and birth of over eight million babies since being implemented in 1978. ART use is currently on the rise, given growing infertility and the increase in conception age among men and women in industrialized countries. Though obstetric and perinatal outcomes have improved over the years, pregnancies achieved by ART still bear increased risks for the mother and the unborn child. Moreover, given that the first generation of ART offspring is now only reaching their forties, the long-term effects of ART are currently unknown. This is important, as there is a wealth of data showing that life-long health can be predetermined by poor conditions during intrauterine development, including irregularities in the structure and functioning of the placenta. In the current review, we aim to summarize the latest available findings examining the effects of ART on the cardiometabolic, cognitive/neurodevelopmental, and behavioral outcomes in the perinatal period, childhood and adolescence/adulthood; and to examine placental intrinsic factors that may contribute to the developmental outcomes of ART offspring. Altogether, the latest knowledge about life outcomes beyond adolescence for those conceived by ART appears to suggest a better long-term outcome than previously predicted. There are also changes in placenta structure and functional capacity with ART. However, more work in this area is critically required, since the potential consequences of ART may still emerge as the offspring gets older. In addition, knowledge of the placenta may help to foresee and mitigate any adverse outcomes in the offspring.

Maternal and perinatal outcomes in women ≥40 years undergoing induction of labor compared with women <35 years: Results from 4027 mothers

AIM

Cesarean section is known to be increased with advanced maternal age in women undergoing induction of labor (IOL), but there is less information regarding other possible adverse maternal and fetal outcomes.

METHODS

Retrospective cohort study of singleton, nulliparous, at-term women undergoing IOL between January 2007 and September 2020. Outcomes studied were: cesarean section, failed induction rate, fetal distress, post-partum hemorrhage, post-partum hysterectomy, and need of transfusion. Neonatal variables analyzed were: Apgar score, umbilical cord pH, need of admission to neonatal intensive care unit, and mortality.

RESULTS

A total of 4027 women met the inclusion criteria; 1968 (48.9%) of mothers were <35 years, 1283 (31.9%) were 35-39 years, 658 (16.3%) were 40-44 years, and 118 (2.9%) were ≥45 years. Results showed a significantly increased incidence of c-section in women ≥35 years, with an OR 1.79 (95% CI 1.50-2.14) for women 40-44 years and OR 3.95 (95% CI 2.66-5.98) for women ≥45 years. The main indication for cesarean delivery was failed IOL, and this risk was also significantly increased in women ≥40 years. These differences remained significant after adjustment for confounding factors. No other adverse maternal or fetal outcomes showed an association with age.

CONCLUSION

Maternal age ≥40 years was associated with an increased risk of c-section after IOL at term compared with younger women, mainly because of failed induction, but no association with other adverse maternal or neonatal outcomes were found in our population. Risks and benefits of IOL in older women should be individually evaluated and adequately discussed with mothers.

Embryo cryopreservation leads to sex-specific DNA methylation perturbations in both human and mouse placentas

In vitro fertilization (IVF) is associated with DNA methylation abnormalities and a higher incidence of adverse pregnancy outcomes. However, which exposure(s), among the many IVF interventions, contributes to these outcomes remains unknown. Frozen embryo transfer (ET) is increasingly utilized as an alternative to fresh ET, but reports suggest a higher incidence of pre-eclampsia and large for gestational age infants. This study examines DNA methylation in human placentas using the 850K Infinium MethylationEPIC BeadChip array obtained after 65 programmed frozen ET cycles, 82 fresh ET cycles and 45 unassisted conceptions. Nine patients provided placentas following frozen and fresh ET from consecutive pregnancies for a paired subgroup analysis. In parallel, eight mouse placentas from fresh and frozen ET were analyzed using the Infinium Mouse Methylation BeadChip array. Human and mouse placentas were significantly hypermethylated after frozen ET compared with fresh. Paired analysis showed similar trends. Sex-specific analysis revealed that these changes were driven by male placentas in humans and mice. Frozen and fresh ET placentas were significantly different from controls, with frozen samples hypermethylated compared with controls driven by males and fresh samples being hypomethylated compared with controls, driven by females. Sexually dimorphic epigenetic changes could indicate differential susceptibility to IVF-associated perturbations, which highlights the importance of sex-specific evaluation of adverse outcomes. Similarities between changes in mice and humans underscore the suitability of the mouse model in evaluating how IVF impacts the epigenetic landscape, which is valuable given limited access to human tissue and the ability to isolate specific interventions in mice.

Perinatal outcome of babies born after using a simplified IVF culture system versus ICSI with sibling oocytes: a prospective cohort study

RESEARCH QUESTION

Is there a difference in perinatal outcome in the same patient cohort for babies conceived following randomization of sibling oocytes allocated to a simplified IVF culture system (SCS) or intracytoplasmic sperm injection (ICSI) followed by conventional culturing?

DESIGN

The study compared the perinatal outcomes of 367 babies born from 1 January 2013 until 31 December 2020 after using split SCS and ICSI insemination of sibling oocytes in a selected group of normo-responsive women, excluding cases of severe male infertility. Primary outcome measures were preterm birth (PTB; <37 weeks' gestation), low birthweight (LBW; <2.5 kg) and small for gestational age (SGA) as a primary outcome parameter while secondary outcome measures included mean birthweight, mean gestational age, extreme prematurity (<32 weeks), very low birthweight (<1.5 kg), perinatal mortality, multiple pregnancy and Caesarean section rate.

RESULTS

A total of 105 and 103 singleton babies were born after fresh embryo transfer (FRET) and 71 and 50 singletons after frozen embryo transfer (FET) in the SCS and ICSI groups, respectively. For babies born after FRET, the LBW rate was 2.9% (3/105) for SCS and 7.8% (8/103) for ICSI (P = 0.10). LBW occurred in 4.2% (3/71) and 0% (0/50) of babies born after the transfer of cryopreserved-thawed SCS and ICSI embryos, respectively (P = 0.14). The rate of PTB was 3.8% and 6.8% for SCS and ICSI in FRET cycles (P = 0.33), and 8.5% and 6.0% for SCS and ICSI in FET cycles (P = 0.62). One congenital malformation was found in the SCS FET group.

CONCLUSION

There was no difference in perinatal outcome for singleton and twin babies born after SCS and ICSI.

The low fetal fraction at the first trimester is associated with adverse pregnancy outcomes in IVF singleton pregnancies with single embryo transfer from frozen cycles

PURPOSE

To study the associations between fetal fraction at the first trimester and subsequent adverse pregnancy outcomes (APOs) in IVF singleton pregnancies with single embryo transfer from frozen cycles.

METHODS

This is a single-center retrospective cohort study on IVF singleton pregnancies with single embryo transfer from frozen cycles. A total of 8457 women were collected between March 2015 and September 2018 from the Center for Reproductive Medicine, Shandong University, China. Participants underwent cell-free DNA (cfDNA) sequencing at 11-13 weeks' gestation. Multivariable logistic regressions were performed with the risk of APOs based on various predictor variables.

RESULTS

A total of 8457 women were included in the analysis of which 1563 (18.48%) women developed one or more APOs. The hypertensive disorders of pregnancy (HDP) (N = 515), gestational diabetes mellitus (GDM) (N = 684), preterm birth (PTB) (N = 567), and low birth weight (LBW) (N = 306) groups had lower fetal fraction compared with the no pregnancy complication (NPC) group (all p values < 0.05). Based on the multivariable logistic regression results, the optimal cutoff values of fetal fraction were 9.30%, 12.54%, 9.10%, 12.65%, and 13.83% for at least one APO, HDP, GDM, PTB, and LBW, respectively. After adjustment for potential maternal confounders, women in the low fetal fraction (LFF) group had a higher risk for the APOs compared with high fetal fraction (HFF) group.

CONCLUSIONS

The fetal fraction in HDP, GDM, PTB, and LBW groups were lower than NPC group in IVF singleton pregnancies with single embryo transfer from frozen cycles in China.

Why does mode of conception affect early breastfeeding outcomes? A retrospective cohort study

Introduction

It is uncertain whether Assisted Reproductive Technology (ART) is associated with an increased risk of poor breastfeeding outcomes and what could be possible mechanisms. This study aimed to examine the effect of mode of conception on breastfeeding outcomes during the first two months postpartum and identify the potential mediating pathways for this relationship.

Methods

A retrospective cohort study was conducted in a sample of 3,565 women with live births. Participants were classified by mode of conception as follows: fertile women who conceived naturally (fertile women; n = 2,857), women with infertility who conceived naturally (sub-fertile women; n = 483), and women with infertility who conceived through ART (women with infertility; n = 310). The infant-feeding patterns were assessed with four-time points before two months postpartum. Binary and multinomial logistic regression and causal mediation analyses were performed.

Results

The rates of breastfeeding initiation and discontinuation across modes of conception were similar. However, infertile and sub-fertile women had 37% (95% CI 1.02, 1.83) and 56% (95% CI 1.06, 2.27) increased risks of introducing formula before the first week postpartum, respectively, and 35% (95% CI 1.01, 1.82) and 52% (95% CI 1.04, 2.24) higher risks of exclusive breastfeeding for less than one week, respectively, compared to fertile women. The relationships were mainly mediated through multiple gestation and admission to neonatal/pediatric intensive care units (NICU/PICU; proportions of mediation were over 50%). The effects of mode of conception on breastfeeding outcomes became not significant in cases of singleton birth.

Conclusions

Sub-fertile women and women with infertility intended to breastfeed but experienced higher perinatal risks in the early postpartum period. Multiple gestation and admission to NICU/PICU forced them to introduce formula earlier than preferred, thus leading to a shorter duration of exclusive breastfeeding. Single embryo transfer policy and breastfeeding support in NICU/PICU could help those women achieve positive early breastfeeding outcomes.

Transfer of thawed frozen embryo versus fresh embryo to improve the healthy baby rate in women undergoing IVF: the E-Freeze RCT

BACKGROUND

Freezing all embryos, followed by thawing and transferring them into the uterine cavity at a later stage (freeze-all), instead of fresh-embryo transfer may lead to improved pregnancy rates and fewer complications during in vitro fertilisation and pregnancies resulting from it.

OBJECTIVE

We aimed to evaluate if a policy of freeze-all results in a higher healthy baby rate than the current policy of transferring fresh embryos.

DESIGN

This was a pragmatic, multicentre, two-arm, parallel-group, non-blinded, randomised controlled trial.

SETTING

Eighteen in vitro fertilisation clinics across the UK participated from February 2016 to April 2019.

PARTICIPANTS

Couples undergoing their first, second or third cycle of in vitro fertilisation treatment in which the female partner was aged < 42 years.

INTERVENTIONS

If at least three good-quality embryos were present on day 3 of embryo development, couples were randomly allocated to either freeze-all (intervention) or fresh-embryo transfer (control).

OUTCOMES

The primary outcome was a healthy baby, defined as a live, singleton baby born at term, with an appropriate weight for their gestation. Secondary outcomes included ovarian hyperstimulation, live birth and clinical pregnancy rates, complications of pregnancy and childbirth, health economic outcome, and State-Trait Anxiety Inventory scores.

RESULTS

A total of 1578 couples were consented and 619 couples were randomised. Most non-randomisations were because of the non-availability of at least three good-quality embryos (n = 476). Of the couples randomised, 117 (19%) did not adhere to the allocated intervention. The rate of non-adherence was higher in the freeze-all arm, with the leading reason being patient choice. The intention-to-treat analysis showed a healthy baby rate of 20.3% in the freeze-all arm and 24.4% in the fresh-embryo transfer arm (risk ratio 0.84, 95% confidence interval 0.62 to 1.15). Similar results were obtained using complier-average causal effect analysis (risk ratio 0.77, 95% confidence interval 0.44 to 1.10), per-protocol analysis (risk ratio 0.87, 95% confidence interval 0.59 to 1.26) and as-treated analysis (risk ratio 0.91, 95% confidence interval 0.64 to 1.29). The risk of ovarian hyperstimulation was 3.6% in the freeze-all arm and 8.1% in the fresh-embryo transfer arm (risk ratio 0.44, 99% confidence interval 0.15 to 1.30). There were no statistically significant differences between the freeze-all and the fresh-embryo transfer arms in the live birth rates (28.3% vs. 34.3%; risk ratio 0.83, 99% confidence interval 0.65 to 1.06) and clinical pregnancy rates (33.9% vs. 40.1%; risk ratio 0.85, 99% confidence interval 0.65 to 1.11). There was no statistically significant difference in anxiety scores for male participants (mean difference 0.1, 99% confidence interval -2.4 to 2.6) and female participants (mean difference 0.0, 99% confidence interval -2.2 to 2.2) between the arms. The economic analysis showed that freeze-all had a low probability of being cost-effective in terms of the incremental cost per healthy baby and incremental cost per live birth.

LIMITATIONS

We were unable to reach the original planned sample size of 1086 and the rate of non-adherence to the allocated intervention was much higher than expected.

CONCLUSION

When efficacy, safety and costs are considered, freeze-all is not better than fresh-embryo transfer.

TRIAL REGISTRATION

This trial is registered as ISRCTN61225414.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 25. See the NIHR Journals Library website for further project information.

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.