Does subfertility explain the risk of poor perinatal outcome after IVF and ovarian hyperstimulation?

Preterm birth in singleton pregnancies conceived by in vitro fertilization or intracytoplasmic sperm injection: an overview of systematic reviews

BACKGROUND

The rate of preterm birth of singletons conceived through in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) is increased, being as high as 15% to 16% across Europe and the United States. However, the underlying etiology, phenotype, and mechanisms initiating preterm birth (PTB) are poorly understood.

OBJECTIVE

To quantify the PTB risk and examine supposed etiology in IVF/ICSI singleton pregnancies compared to naturally conceived.

STUDY DESIGN

Overview of reviews including all available systematic reviews with meta-analysis comparing PTB risk in IVF/ICSI and naturally conceived singletons. A comprehensive search of PubMed/MEDLINE, Embase, Scopus, and Cochrane Library databases was performed up to December 31, 2023. Information available on etiology, phenotype, initiation of PTB, and relevant moderators was retrieved and employed for subgroup analyses. Random-effects meta-analysis models were used for pooling effect measures. Estimates were presented as odds ratios (ORs) with 95% confidence intervals (CIs). The extent of overlap in the original studies was measured using the corrected covered area assessment. The quality of the included reviews was evaluated with the AMSTAR 2 tool. The Grading of Recommendations Assessment, Development and Evaluation approach was applied to rate evidence certainty. The protocol was registered on PROspective Register of Systematic Reviews (CRD42023411418).

RESULTS

Twelve meta-analyses (16,522,917 pregnancies; ˃433,330 IVF/ICSI) were included. IVF/ICSI singletons showed a significantly higher PTB risk compared to natural conception (PTB ˂37 weeks: OR: 1.72, 95% CI: 1.57-1.89; PTB<32 weeks: OR: 2.19, 95% CI: 1.82-2.64). Influential analysis reinforced the strength of this association. Subgroup analyses investigating supposed etiology revealed a comparable risk magnitude for spontaneous PTB (OR: 1.79, 95% CI: 1.56-2.04) and a greater risk for iatrogenic PTB (OR: 2.28, 95% CI: 1.72-3.02). PTB risk was consistent in the subgroup of conventional IVF (OR: 1.95, 95% CI: 1.76-2.15) and higher in the subgroup of fresh only (OR: 1.79, 95% CI: 1.55-2.07) vs frozen-thawed embryo transfers (OR: 1.39, 95% CI: 1.34-1.43). There was minimal study overlap (13%). The certainty of the evidence was graded as low to very low.

CONCLUSION

Singletons conceived through IVF/ICSI have a 2-fold increased risk of PTB compared to natural conception, despite the low certainty of the evidence. There is paucity of available data on PTB etiology, phenotype, or initiation. The greater risk increase is observed in fresh embryo transfers and involves iatrogenic PTB and PTB ˂32 weeks, likely attributable to placental etiology. Future studies should collect data on PTB etiology, phenotype, and initiation. IVF/ICSI pregnancies should undertake specialistic care with early screening for placental disorders, cervical length, and growth abnormalities, allowing appropriate timely follow-up, preventive measures, and therapeutic interventions strategies.

Children born after assisted reproduction more commonly carry a mitochondrial genotype associating with low birthweight

Children conceived through assisted reproductive technologies (ART) have an elevated risk of lower birthweight, yet the underlying cause remains unclear. Our study explores mitochondrial DNA (mtDNA) variants as contributors to birthweight differences by impacting mitochondrial function during prenatal development. We deep-sequenced the mtDNA of 451 ART and spontaneously conceived (SC) individuals, 157 mother-child pairs and 113 individual oocytes from either natural menstrual cycles or after ovarian stimulation (OS) and find that ART individuals carried a different mtDNA genotype than SC individuals, with more de novo non-synonymous variants. These variants, along with rRNA variants, correlate with lower birthweight percentiles, independent of conception mode. Their higher occurrence in ART individuals stems from de novo mutagenesis associated with maternal aging and OS-induced oocyte cohort size. Future research will establish the long-term health consequences of these changes and how these findings will impact the clinical practice and patient counselling in the future.

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.

In-Hospital Complications in Pregnancies Conceived by Assisted Reproductive Technology

Background Assisted reproductive technology (ART) has emerged as a common treatment option for infertility, a problem that affects an estimated 48 million couples worldwide. Advancing maternal age with increasing prepregnancy cardiovascular risk factors, such as chronic hypertension, obesity, and diabetes, has raised concerns about pregnancy complications associated with ART. However, in-hospital complications following pregnancies conceived by ART are poorly described. Methods and Results To assess the patient characteristics, obstetric outcomes, vascular complications and temporal trends of pregnancies conceived by ART, we analyzed hospital deliveries conceived with or without ART between January 1, 2008, and December 31, 2016, from the United States National Inpatient Sample database. We included 106 248 deliveries conceived with ART and 34 167 246 deliveries conceived without ART. Women who conceived with ART were older (35 versus 28 years; P<0.0001) and had more comorbidities. ART-conceived pregnancies were independently associated with vascular complications (acute kidney injury: adjusted odds ratio [aOR], 2.52; 95% CI 1.99-3.19; and arrhythmia: aOR, 1.65; 95% CI, 1.46-1.86), and adverse obstetric outcomes (placental abruption: aOR, 1.57; 95% CI, 1.41-1.74; cesarean delivery: aOR, 1.38; 95% CI, 1.33-1.43; and preterm birth: aOR, 1.26; 95% CI, 1.20-1.32), including in subgroups without cardiovascular disease risk factors or without multifetal pregnancies. Higher hospital charges ($18 705 versus $11 983; P<0.0001) were incurred compared with women who conceived without ART. Conclusions Pregnancies conceived by ART have higher risks of adverse obstetric outcomes and vascular complications compared with spontaneous conception. Clinicians should have detailed discussions on the associated complications of ART in women during prepregnancy counseling.

Cerebral palsy in children born after assisted reproductive technology: a meta-analysis

BACKGROUND

Several studies have assessed the association between cerebral palsy (CP) and assisted reproductive technology (ART), but the results remain controversial. We conducted a meta-analysis to evaluate the risk of CP after ART compared with natural conceptions and to examine CP risk separately in ART singletons, multiples and preterm births.

METHODS

Web-based databases (PubMed, Embase, the Cochrane Library, and Web of Science) were searched until November 22, 2020. Studies which compare CP rates after ART with natural conceptions were included. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. Effect estimates were extracted and combined using the fixed-effects or random-effects model depending on the heterogeneity test.

RESULTS

There were nine studies included in the meta-analysis. The included studies were of moderate or high quality. A significantly higher risk of CP [odds ratio (OR) = 2.17, 95% confidence interval (CI) 1.72-2.74] was found in ART children (n = 89,214) compared with naturally conceived children (n = 4,160,745). The significantly higher risk decreased when data were restricted to singletons (OR = 1.36, 95% CI 1.16-1.59) and disappeared when data were restricted to multiples (OR = 1.05, 95% CI 0.86-1.29) or preterm births (OR = 1.53, 95% CI 0.66-3.56). Subgroup and sensitivity analyses indicated that the overall results were robust.

CONCLUSIONS

The risk of CP is increased more than two-fold after ART. This increased risk is largely due to increased rates of multiple birth and preterm delivery in ART children.

Obstetric and perinatal outcomes of in vitro fertilization and natural pregnancies in the same mother

OBJECTIVE

To compare obstetric and perinatal outcomes between pregnancies conceived using in vitro fertilization (IVF) and natural pregnancies of the same women.

DESIGN

This was a case-control study of deliveries between November 2008 and January 2020 in which each IVF pregnancy was matched to a natural pregnancy of the same woman (1:1 ratio).

SETTING

University hospital.

PATIENT(S)

We included women with consecutive live singleton deliveries (>24 weeks of gestation) at the Edith Wolfson Medical Center. We excluded IVF pregnancies attained using egg donation.

INTERVENTION(S)

In vitro fertilization-attained pregnancies (as compared with natural ones).

MAIN OUTCOME MEASURE(S)

Primary outcome: preterm birth (PTB).

SECONDARY OUTCOMES

small for gestational age (SGA) neonates and pregnancy-induced hypertension (PIH; gestational hypertension or pre-eclampsia).

RESULT(S)

A total of 544 IVF pregnancies were matched to 544 natural pregnancies, each in the same woman. In 292 women (53.7%), the natural pregnancy preceded the IVF pregnancy. Maternal age was significantly higher in IVF deliveries. Gestational age at delivery and the rates of PTB, PIH, instrumental delivery, cesarean delivery, and SGA neonates were comparable between IVF and natural pregnancies. Birth weight was slightly lower in IVF pregnancies. On multivariate analysis, IVF was not independently associated with PTB, SGA, or PIH after adjustment for confounders.

CONCLUSION(S)

When compared in a cohort of the same women, natural and IVF-attained pregnancies did not differ with regard to obstetric and perinatal outcomes.

Cognitive and behavioural outcome of children born after IVF at age 9 years

STUDY QUESTION

Do ovarian stimulation (OS) and the in vitro laboratory procedures affect offsprings' cognitive and behavioural outcome at 9 years?

SUMMARY ANSWER

OS and the in vitro laboratory procedures or the combination of both were not associated with cognitive and behavioural outcome at age 9 years.

WHAT IS KNOWN ALREADY

ART is not associated with an adverse short-term developmental outcome of the offspring, but limited knowledge is available on the offspring's long-term neurodevelopmental condition.

STUDY DESIGN, SIZE, DURATION

A 9-year longitudinal, assessor-blinded, prospective follow-up study of 169 out of 215 singletons (79%) born between March 2005 and December 2006 was performed.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Singletons born following IVF or ICSI with OS (n = 57), born after modified natural cycle IVF/ICSI (MNC-IVF/ICSI; n = 46) and born after natural conception to subfertile couples (Sub-NC; n = 66), were assessed at 9 years. This study design, with two ART groups and a subfertile reference group, allows for disentangling the effects of OS and ART procedures on developmental outcome. Cognitive outcome was evaluated with the Wechsler abbreviated scale of intelligence and the NEPSY-II. Behaviour was assessed with the child behaviour checklist (CBCL) and teacher report form (TRF). Univariable analyses and multiple linear regression models were used.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no significant difference in intelligence quotient (IQ) scores between ART groups (mean IQ (95% CI): OS 114.8 (83.2-142.6); MNC 114.0 (90.2-140.8); Sub-NC 115.4 (87.9-141.2), P = 0.746). Multivariable analyses did not reveal a statistically significant association between ART group and total, verbal and performance IQ. CBCL and TRF scores did not differ significantly between ART groups (P = 0.090 and 0.507, respectively). Multivariable analyses did not demonstrate a statistically significant association between ART group and CBCL and TRF total, or internalising and externalising T-scores. No significant correlations between time to pregnancy (TTP)-a proxy for the severity of parental subfertility-and outcome measures were found (Spearman rho between -0.050 and 0.049, NS), which was confirmed with multivariable analyses.

LIMITATIONS, REASONS FOR CAUTION

The attrition rate of 21% may be considered as a limitation of the study; however, after a follow-up period of 9 years, this rate is generally considered acceptable, and there were no significant differences in background characteristics between children with and without follow-up, making an attrition-related selection bias less likely. Another limitation of the study is the relatively small sample size, which could contribute to selection bias, hamper generalizability to the ART population and lead to false negative findings as a result of underpowering. An a priori power analysis on total IQ indicated that the OS-IVF/ICSI and Sub-NC groups should contain 64 children, confirming that our study including 57 and 66 children, respectively, was slightly underpowered.

WIDER IMPLICATIONS OF THE FINDINGS

Our study indicated that OS and the in vitro laboratory procedures or the combination of both and TTP were not associated with cognitive and behavioural outcome at 9 years. These are reassuring results for both parents and clinicians involved in ART.

STUDY FUNDING/COMPETING INTEREST(S)

The study was financially supported by the University Medical Center Groningen (UMCG), two graduate schools of the UMCG (BCN and SHARE) and the Cornelia Stichting. The sponsors of the study had no role in study design, data collection, data analysis, data interpretation or writing of the report. The authors have no conflicts of interest to declare.

Comparison of perinatal outcomes between spontaneous vs. commissioned cycles in gestational carriers for single and same-sex male intended parents

PURPOSE

To determine whether gestational carrier (GC) in vitro fertilization (IVF) cycles (commissioned cycles) for same-sex or single male intended parents have an increased incidence of adverse perinatal outcomes compared with spontaneous cycles in the same GCs.

DESIGN

GC singleton pregnancies were identified from a database of 895 commissioned cycles from a large fertility center. Of these, 78 commissioned cycles met inclusion and exclusion criteria and were compared with 71 spontaneous cycles by the same GCs. The primary outcome was the composite score for adverse perinatal outcomes. Secondary outcomes included mode of delivery, birthweight, and gestational age. Chi-square test of association and Mann-Whitney U tests were used to compare categorical and continuous variables between the cohorts, respectively. Logistic and linear regressions controlling for GC age were constructed to determine the influence of GC cycle type on adverse perinatal outcomes.

RESULTS

Commissioned cycles were significantly associated with adverse perinatal outcomes (25.6% vs. 9.9%; p = 0.02) and lower average gestational age (38.7 ± 1.5 vs. 39.4 ± 0.9; p < 0.001) compared with spontaneous cycles. Commissioned cycle increased the likelihood of adverse perinatal outcomes (OR 3.3; p = 0.03) and was a significant independent predictor of a lower average gestational age (β = 0.897; p < 0.001). There were no significant differences in the incidence of vaginal deliveries or cesarean sections between commissioned and spontaneous cycles.

CONCLUSIONS

Commissioned cycles confer a greater incidence of composite perinatal complications and were independently associated with a lower average gestational age when compared with spontaneous pregnancies carried by the same GC despite a confirmed healthy uterine environment, sperm samples, and donor oocytes.

Risk of gestational diabetes mellitus following assisted reproductive technology: systematic review and meta-analysis of 59 cohort studies

OBJECTIVE

The use of assisted reproductive technology (ART) has been associated with an increased risk of gestational diabetes mellitus (GDM) in previous studies, but its risk has not been consistent. Therefore, we aimed to estimate the risk of GDM in women who conceived with ART via a systematic review and meta-analysis of cohort studies.

METHODS

ISI Web of Knowledge, Medline/PubMed, Scopus, and Embase databases were searched to identify studies that evaluated the risk of GDM through May 2017 using the relevant keywords. Two reviewers independently performed the screening, data extraction, and quality assessment. Meta-analysis was performed with a random effects model.

RESULTS

The search yielded 957 records relating to GDM and use of ART, from which 59 eligible cohorts were selected for meta-analysis (n = 96,785). There was evidence of substantial heterogeneity among these studies (χ₍₅₈₎² = 3072.34, p < .001; I²=98.1%). The pooled estimate of GDM risk using the random effects model was 9.00% (95% CI: 7.90-10.20). Visual inspection of the funnel plot indicated the presence of low publication bias, but Egger's test did not reveal publication bias.

CONCLUSIONS

The findings revealed that the risk of GDM was very high among women who conceived with ART treatment. GDM screening, management, and improved care are vital in ART pregnancy.

Maternal and environmental risk factors for neonatal AKI and its long-term consequences

Acute kidney injury (AKI) is a common and life-threatening complication in critically ill neonates. Gestational risk factors for AKI include premature birth, intrauterine growth restriction and low birthweight, which are associated with poor nephron development and are often the consequence of pre-gestational and gestational factors, such as poor nutritional status. Our understanding of how to best optimize renal development and prevent AKI is in its infancy; however, the identification of pre-gestational and gestational factors that increase the risk of adverse neonatal outcomes and the implementation of interventions, such as improving nutritional status early in pregnancy, have the potential to optimize fetal growth and reduce the risk of preterm birth, thereby improving kidney health. The overall risk of AKI among critically ill and premature neonates is exacerbated postnatally as these infants are often exposed to dehydration, septic shock and potentially nephrotoxic medications. Strategies to improve outcomes - for example, through careful evaluation of nephrotoxic drugs - may reduce the incidence of AKI and its consequences among this population. Management strategies and updated technology that will support neonates with AKI are greatly needed. Extremely premature infants and those who survive an episode of AKI should be screened for chronic kidney disease until early adulthood. Here, we provide an overview of our current understanding of neonatal AKI, focusing on its relationship to preterm birth and growth restriction. We describe factors that prevent optimal nephrogenesis during pregnancy and provide a framework for future explorations designed to maximize outcomes in this vulnerable population.

Ovarian response to stimulation and suboptimal endometrial development are associated with adverse perinatal outcomes in intracytoplasmic sperm injection cycles

Objective:

To study which factors affect perinatal outcomes in intracytoplasmic sperm injection (ICSI) cycles.

Methods:

Data was obtained from 402 live births born to 307 patients undergoing ICSI cycles in a private university-affiliated IVF center between Jan/2014 and Dec/2015. The influences of the cycles' characteristics on the number of gestational weeks to livebirth (GW), baby birth weight (BW), and baby birth length (BL) were evaluated by linear regression models, adjusted for maternal age and body mass index, number of transferred embryos, number of gestational sacs, and number of born infants. In a subsequent analysis, GW, BW and baby sex were utilized for cycle classification into the groups Appropriate for gestational age (AGA n=256) and Small for gestational age (SGA n=146), which were compared by general linear models adjusted for the same confounder variables.

Results:

The number of follicles (β=-0.069 p=0.018) and retrieved oocytes (β=-0.087 p=0.049) were negatively correlated with BL. The endometrial thickness was positively correlated with GW (β=0.198 p=0.003) and BW (β=28.351 p=0.044). When each baby was classified into AGA and SGA groups, it was observed that SGA babies were derived from cycles with higher estradiol levels at hCG day (SGA: 3897.01±550.35 vs. AGA: 2324.78±101.86 p=0.006) and higher number of retrieved oocytes (SGA: 16.70±1.78 vs. AGA: 12.92±0.42 p=0.042). The endometrial thickness was significantly lower in the SGA group (SGA: 10.2±0.23 vs. AGA: 11.68±0.17 vs. p=0.029).

Conclusion:

Higher ovarian response to stimulation and suboptimal endometrial development are associated with adverse perinatal outcomes in ICSI cycles.

Assisted reproductive technology and the risk of pregnancy-related complications and adverse pregnancy outcomes in singleton pregnancies: a meta-analysis of cohort studies

OBJECTIVE

To determine whether there are any increases in pregnancy-related complications and adverse pregnancy outcomes in singleton pregnancies after assisted reproductive technology (ART) compared with those conceived naturally.

DESIGN

Meta-analysis.

SETTING

University-affiliated teaching hospital.

PATIENT(S)

Singleton pregnancies conceived with ART and naturally.

INTERVENTION(S)

PubMed, Google Scholar, Cochrane Libraries and Chinese database were searched through March 2015 to identify studies that met pre-stated inclusion criteria. Either a fixed- or a random-effects model was used to calculate the overall combined risk estimates. Subgroup analysis was performed to explore potential heterogeneity moderators.

MAIN OUTCOME MEASURE(S)

Pregnancy-related complications and adverse pregnancy outcomes.

RESULT(S)

Fifty cohort studies comprising 161,370 ART and 2,280,241 spontaneously conceived singleton pregnancies were identified. The ART singleton pregnancies had a significantly increased risk of pregnancy-induced hypertension (relative risk [RR] 1.30, 95% confidence interval [CI] 1.04-1.62; I(2) = 79%), gestational diabetes mellitus (RR 1.31, 95% CI 1.13-1.53; I(2) = 6%), placenta previa (RR 3.71, 95% CI 2.67-5.16; I(2) = 72%), placental abruption (RR 1.83, 95% CI 1.49-2.24; I(2) = 22%), antepartum hemorrhage (RR 2.11, 95% CI 1.86-2.38; I(2) = 47%), postpartum hemorrhage (RR 1.29, 95% CI 1.06-1.57; I(2) = 65%), polyhydramnios (RR 1.74, 95% CI 1.24-2.45; I(2) = 0%), oligohydramnios (RR 2.14, 95% CI 1.53-3.01; I(2) = 0%), cesarean sections (RR 1.58, 95% CI 1.48-1.70; I(2) = 92%), preterm birth (RR 1.71, 95% CI 1.59-1.83; I(2)=80%), very preterm birth (RR 2.12, 95% CI 1.73-2.59; I(2) = 90%), low birth weight (RR 1.61, 95% CI 1.49-1.75; I(2) = 80%), very low birth weight (RR 2.12, 95% CI 1.84-2.43; I(2) = 67%), small for gestational age (RR 1.35, 95% CI 1.20-1.52; I(2) = 82%), perinatal mortality (RR 1.64, 95% CI 1.41-1.90; I(2)=45%), and congenital malformation (RR 1.37, 95% CI 1.29-1.45; I(2)=41%). Relevant heterogeneity moderators have been identified by subgroup analysis. Sensitivity analysis yielded consistent results. No evidence of publication bias was observed.

CONCLUSION(S)

The ART singleton pregnancies are associated with higher risks of adverse obstetric outcomes. Obstetricians should manage these pregnancies as high risk.

Comparison of different stimulation protocols used in in vitro fertilization: a review

Infertility is one of the major medical problems in the western world caused by genetic or epigenetic factors, or both, which has led to continuous research and advancements in the field of assisted reproductive technology (ART). Many stimulation protocols are available for controlled ovarian hyperstimulation (COH) in in vitro fertilization (IVF). This review compares the agonist long protocol, antagonist protocol and minimal stimulation protocol. Gonadotropin-releasing hormone (GnRH) antagonist and minimal stimulation protocol has shorter duration of treatment and less gonadotropin use. GnRH agonist long protocol is better in folliculogenesis and pregnancy rate, which is the imperative goal of COH. Despite its costly and lengthy approach, GnRH agonist long protocol has delivered satisfactory results in most women. On the other hand, patients with poor ovarian reserve may have greater advantage when considering minimal stimulation protocol. Evidently, it is crucial to have a larger scale studies with more focused comparisons, which take into account the differences in patients' response criteria and additional confounding variables (age, BMI, previous IVF outcomes etc.), in order to reach to a more definite conclusions.

Fertility treatments and adverse perinatal outcomes in a population-based sampling of births in Florida, Maryland, and Utah: a cross-sectional study

OBJECTIVE

To investigate perinatal outcomes associated with fertility treatments, including assisted reproductive technology (ART), intrauterine insemination with ovulation stimulation (IUI), and ovulation stimulation alone (OS).

DESIGN

Population-representative cross-sectional survey of women with live births, 2004-2008.

SETTING

Florida, Maryland, and Utah, USA.

SAMPLE

21 803 women, weighted to represent 1 022 597 women.

METHODS

Survey and birth certificate data were analysed with logistic regression models adjusted for age, education, race, income, and parity, using separate models for singletons and all births. We used two referent groups: (1) women who never used fertility treatment and (2) subfertile women conceiving without treatment.

MAIN OUTCOME MEASURES

Preterm birth (<37 weeks), very preterm birth (<34 weeks), low birthweight (<2500 g), and very low birthweight (<1500 g).

RESULTS

Referent group 1: In singletons, ART was associated with preterm birth (OR 3.28; 95% CI 1.74, 6.20) and low birthweight (OR 2.91; 95% CI 1.99, 4.26). OS was also associated with low birthweight (OR 1.62; 95% CI 1.19, 2.19). Including all births, treatment was associated with preterm birth and low birthweight: ART (OR 6.21; 95% CI 4.21, 9.16 and OR 6.51; 95% CI 4.85, 8.73); IUI (OR 2.10; 95% CI 1.24, 3.56 and OR 2.41; 95% CI 1.54, 3.76); OS (OR 1.40; 95% CI 1.01, 1.94 and OR 2.10; 95% CI 1.60, 2.75), respectively. Referent group 2: ART was associated with both outcomes in all births, but not singletons.

CONCLUSIONS

Preterm birth and low birthweight associated with fertility treatments are largely attributable to multiple gestation, but are also related to underlying subfertility.

TWEETABLE ABSTRACT

Preterm birth is associated with subfertility, and with fertility treatments through multiple gestation.

Methodology for establishing a population-based birth cohort focusing on couple fertility and children's development, the Upstate KIDS Study

BACKGROUND

Critical data gaps remain regarding infertility treatment and child development. We assessed the utility of a birth certificate registry for developing a population cohort aimed at answering such questions.

METHODS

We utilised the Upstate New York livebirth registry (n = 201,063) to select births conceived with (n = 4024) infertility treatment or exposed infants, who were then frequency-matched by residence to a random sample of infants conceived without (n = 14,455) treatment or unexposed infants, 2008-10. Mothers were recruited at 2-4 months postpartum and queried about their reproductive histories, including infertility treatment for comparison with birth certificate data. Overall, 1297 (32%) mothers of exposed and 3692 of unexposed (26%) infants enrolled.

RESULTS

Twins represented 22% of each infant group. The percentage of infants conceived with/without infertility treatment was similar whether derived from the birth registry or maternal report: 71% none, 16% drugs or intrauterine insemination, and 14% assisted reproductive technologies (ART). Concordant reporting between the two data sources was 93% for no treatment, 88% for ART, and 83% for fertility drugs, but differed by plurality. Exposed infants had slightly (P < 0.01) earlier gestations than unexposed infants (38.3 ± 2.8 and 38.7 ± 2.7 weeks, respectively) based upon birth certificates but not maternal report (38.7 ± 2.7 and 38.7 ± 2.9, respectively). Conversely, mean birthweight was comparable using birth certificates (3157 ± 704 and 3194 ± 679 g, respectively), but differed using maternal report (3167 ± 692 and 3224 ± 661, respectively P < 0.05).

CONCLUSIONS

The birth certificate registry is a suitable sampling framework as measured by concordance with maternally reported infertility treatment. Future efforts should address the impact of factors associated with discordant reporting on research findings.

Maternal, perinatal and long-term outcomes after assisted reproductive techniques (ART): implications for clinical practice

The use of assisted reproductive techniques (ART) is on the rise throughout the world and the number of babies born as a result of ART has reached an estimated total of 5 million since the world's first, Louise Brown, was born in 1978. Data from many prospective and retrospective studies have suggested increased risks of adverse maternal, perinatal and long-term outcomes after ART compared to natural conception. Recent research suggests that underlying maternal factors rather than ART methods themselves play a significant role in causing such outcomes. Couples attempting ART need to be provided with accurate and reliable information on risks of adverse reproductive outcomes and reassured that absolute risks appear small. Clinicians need to remain vigilant about increased risk of pregnancy complications and formulate a plan of care for the woman, from periconception to the puerperium, which aims to prevent or minimise maternal and perinatal morbidity. This review attempts to summarise the available data on reproductive outcomes after ART and provide guidance to the obstetricians and primary care physicians about management of ART pregnancies.

Reproductive outcomes after assisted conception

The last three decades have witnessed a dramatic increase in the use of assisted reproductive technology (ART) so that now, in developed countries, 1.7% to 4.0% of all children are born after ART. Although absolute risks appear small, data from prospective and retrospective studies indicate increased risks of adverse maternal and perinatal outcomes after ART as compared with spontaneous conception. Recent studies suggest that underlying maternal factors and subfertility play an important role in some of these outcomes rather than the ART procedure itself. A significant risk of assisted conception is multiple pregnancies, but even singleton pregnancies achieved by ART are at a higher risk of hypertensive disease, diabetes, prematurity, low birth weight, and perinatal mortality even after adjusting for confounders. Couples undergoing ART procedures should be counseled in advance regarding increased risks of pregnancy complications and higher rates of obstetric interventions. Although conflicting data exist, studies of children born from ART suggest increased rates of congenital malformations, imprinting disorders (Beckwith-Wiedemann syndrome and Angelman syndrome), and marginally increased risk of cancer. However, the current evidence is inadequate, and prospective long-term studies are needed to eliminate the effect of confounders and draw definite conclusions about the long-term outcomes after ART. The absolute risk of imprinting disorders remains small, and routine screening is not recommended at present. The long-term outcomes after ART are difficult to evaluate because of the variability in ART methods and data reporting, and there is a need for standardized methodology for follow-up after ART.

Why do singletons conceived after assisted reproduction technology have adverse perinatal outcome? Systematic review and meta-analysis

BACKGROUND

Assisted reproduction technology (ART) is used worldwide, at increasing rates, and data show that some adverse outcomes occur more frequently than following spontaneous conception (SC). Possible explanatory factors for the well-known adverse perinatal outcome in ART singletons were evaluated.

METHODS

PubMed and Cochrane databases from 1982 to 2012 were searched. Studies using donor or frozen oocytes were excluded, as well as those with no control group or including <100 children. The main outcome measure was preterm birth (PTB defined as delivery <37 weeks of gestation), and a random effects model was used for meta-analyses of PTB. Other outcomes were very PTB, low-birthweight (LBW), very LBW, small for gestational age and perinatal mortality.

RESULTS

The search returned 1255 articles and 65 of these met the inclusion criteria. The following were identified as predictors for PTB in singletons: SC in couples with time to pregnancy (TTP) > 1 year versus SC singletons in couples with TTP ≤ 1 year [adjusted odds ratio (AOR) 1.35, 95% confidence interval (CI) 1.22, 1.50]; IVF/ICSI versus SC singletons from subfertile couples (TTP > 1 year; AOR 1.55, 95% CI 1.30, 1.85); conception after ovulation induction and/or intrauterine insemination versus SC singletons where TTP ≤ 1 year (AOR 1.45, 95% CI 1.21, 1.74); IVF/ICSI singletons versus their non-ART singleton siblings (AOR 1.27, 95% CI 1.08, 1.49). The risk of PTB in singletons with a 'vanishing co-twin' versus from a single gestation was AOR of 1.73 (95% CI 1.54, 1.94) in the narrative data. ICSI versus IVF (AOR 0.80, 95% CI 0.69-0.93), and frozen embryo transfer versus fresh embryo transfer (AOR 0.85, 95% CI 0.76, 0.94) were associated with a lower risk of PTB.

CONCLUSIONS

Subfertility is a major risk factor for adverse perinatal outcome in ART singletons, however, even in the same mother an ART singleton has a poorer outcome than the non-ART sibling; hence, factors related to the hormone stimulation and/or IVF methods per se also may play a part. Further research is required into mechanisms of epigenetic modification in human embryos and the effects of cryopreservation on this, whether milder ovarian stimulation regimens can improve embryo quality and endometrial conditions, and whether longer culture times for embryos has a negative influence on the perinatal outcome.

Trends and correlates of good perinatal outcomes in assisted reproductive technology

OBJECTIVE

To estimate trends in good perinatal outcomes (singleton live births at term with birthweight more than 2,500 g) among live births after assisted reproductive technology in the United States from 2000 to 2008, and associated factors among singletons in 2008.

METHODS

Using retrospective cohort data from the National Assisted Reproductive Technology Surveillance System from 2000 to 2008, we calculated relative change and χ tests for trend in the proportion of good perinatal outcomes among assisted reproductive technology live births (n=444,909) and liveborn singletons (n=222,500). We conducted univariable analyses followed by multiple logistic regression to estimate the effects of various characteristics on the outcome among singletons born in 2008 after fresh, nondonor assisted reproductive technology cycles (n=20,780).

RESULTS

The proportion of good perinatal outcomes among all liveborn neonates increased from 38.6% in 2000 to 42.5% in 2008, whereas it declined marginally among singletons from 83.6% to 83.4%. One previous birth, transfer of fewer than three embryos, and the presence of fewer than three fetal hearts on 6-week ultrasound examination were associated with good perinatal outcome among singletons. Non-Hispanic black race, tubal factor infertility, uterine factor infertility, ovulatory disorder, and 5-day embryo culture were associated with reduced odds for a good outcome. The strongest association was the presence of one fetal heart compared with more than two (adjusted odds ratio 2.43, 95% confidence interval 1.73-3.42).

CONCLUSION

From 2000 to 2008, good perinatal outcomes increased among assisted reproductive technology live births. Among singleton live births, odds for good outcome were greatest with the presence of a single fetal heart and lowest in women of non-Hispanic black race.

LEVEL OF EVIDENCE

II.

Markers of transmembrane and energy exchange in cells of terminal placental villi in spontaneous and induced pregnancy

We performed a comparative morphological study of the placentas in spontaneous and induced pregnancy. Immunohistochemical analysis revealed pronounced decrease in the expression of markers of transmembrane (α-SNAP 23, annexin 3) and energy (ferritin light chain, ATP5J) in placental terminal villi.

Comparison of the pregnancy outcomes of subfertile women after infertility treatment and in naturally conceived pregnancies

BACKGROUND

Adverse obstetric outcomes in pregnancies achieved through assisted reproductive technology (ART) could either be due to the technology or to the underlying subfertility or to both. To address this issue, we compared the pregnancy outcomes of singletons conceived naturally after a long time to pregnancy (TTP) with those of ART pregnancies.

METHODS

We analysed an existing birth database. Altogether 428 ART pregnancies were compared with 928 spontaneously conceived pregnancies with TTP of 2 years or more, during the period 1989-2007 at Kuopio University Hospital, Finland. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for pregnancy outcomes.

RESULTS

Between treated and untreated subfertile women no significant differences were found in the rates of Caesarean sections (OR 1.21, 95% CI 0.89-1.64), preterm births (OR 1.28, 95% CI 0.81-2.03), small for gestational age (SGA) birthweight (OR 0.95, 95% CI 0.65-1.39), need of neonatal intensive care (OR 1.28, 95% CI 0.88-1.88) or low Apgar scores (OR 1.19, 95% CI 0.47-3.04). However, compared with pregnancies of women with TTP 0-6 months, ART pregnancies had significantly increased risks of preterm or very preterm birth, low birthweight and need of neonatal intensive care.

CONCLUSIONS

The risks of preterm birth, SGA, need for neonatal intensive care and low Apgar scores were not significantly different between subfertile women who conceived spontaneously and those who conceived through ART indicating that maternal factors relating to subfertility and not only infertility treatment are associated with adverse pregnancy outcomes.

The birth certificate as an efficient means of identifying children conceived with the help of infertility treatment

Recent work suggests that infertility treatment is associated with adverse child health outcomes. In exploring various methods of assembling a cohort of children conceived by infertility treatment, the authors conducted a validation study of the assisted reproductive technology and infertility drug use check boxes on the Massachusetts birth certificate. Using 2001 and 2002 data, the authors conducted telephone interviews with 399 women whose child's birth certificate had at least one of the boxes checked along with 185 women who were over age 42 years or who delivered twins or higher order multiples to compare the check box information with maternal report. Among the 579 women with available information, the birth certificate was fully concordant with respect to infertility treatment status for 271 (47%) women, partially concordant for 248 (43%) women, and discordant for 60 (10%) women. Agreement between the birth certificate and maternal report was good for singletons (weighted kappa = 0.66) but was found to be very poor among twins and higher order multiples (weighted kappa = 0.05). The authors concluded that birth certificates are an efficient means of locating children conceived with the help of infertility treatment but that they are not appropriate for identifying type of treatment.

Birth outcomes of intended pregnancies among women who used assisted reproductive technology, ovulation stimulation, or no treatment

OBJECTIVE

To study birth outcomes among live born infants conceived by women who used infertility treatment.

DESIGN

Population-based surveillance of women who recently delivered a live infant.

SETTING

The birth outcomes among infants whose mothers used assisted reproductive technology (ART) or ovulation stimulation medications alone were compared with the outcomes of infants conceived without treatment.

PATIENT(S)

Stratified random sample of women who were attempting conception and gave birth to a live infant in six US states (n = 16,748).

INTERVENTION(S)

Assisted reproductive technology and ovulation stimulation.

MAIN OUTCOME MEASURE(S)

Adjusted odds ratios for perinatal outcomes.

RESULT(S)

The prevalence of infertility treatment use overall among women attempting conception was 10.9% (5.4% ART procedures, 5.5% ovulation stimulation medications). Singletons of mothers who received ART procedures were more likely to be born with low birthweight, preterm, and small for gestational age (SGA) than singleton infants conceived without treatment. Singleton infants of mothers who used ovulation stimulation medications alone were more likely to be SGA than singleton infants conceived without treatment. No differences were found between ART and no treatment twin infants.

CONCLUSION(S)

Among singleton infants, ART is associated with decreased fetal growth, decreased gestational length, and SGA; ovulation stimulation alone is associated with SGA.

High-response intrauterine insemination cycles converted to low-cost in vitro fertilization

Background:

There is a trend to cancel intrauterine insemination (IUI) in women with a high response. The aim of this study was to evaluate the efficacy of low-cost in vitro fertilization (IVF) in high-response IUI cycles in comparison with conventional IVF.

Methods and materials:

A total of 46 women were included in the study. Group A (study group) included 23 women with hyper-response to IUI cycles who were converted to IVF. They received oral letrozole 2.5 mg twice daily from days 3–7 of the menstrual cycle, along with 75 International Units (IU) of recombinant follicle-stimulating hormone on days 3 and 8. Group B (control group) underwent conventional IVF, and received downregulation with a gonadotrophin-releasing hormone agonist followed by stimulation with recombinant follicle-stimulating hormone 150–300 IU/day. Ovulation was triggered by 10,000 IU of human chorionic gonadotrophin, followed by IVF and embryo transfer. The primary outcome measure analyzed was pregnancy rates in both groups.

Results:

The study group received a significantly lower (P = 0.001) total dose of follicle-stimulating hormone and had significantly (P = 0.002) decreased levels of terminal estradiol. Although the pregnancy rate (30.43% in the study group versus 39.13% in the conventional group) per stimulated cycle was higher in the conventional IVF group, the miscarriage rate (study group 4.34% versus conventional group 13.04%) was also higher, and hence the take-home baby rate (study group 26.08% versus conventional group 30.43%) was more or less similar in both the groups.

Conclusion:

IVF can be offered to women having a high response to IUI cycles with good pregnancy rates and at low cost compared with use of a conventional protocol, and therefore can be considered more patient-friendly in selected cases.

In vitro fertilization and adverse childhood outcomes: what we know, where we are going, and how we will get there. A glimpse into what lies behind and beckons ahead

The majority of perinatal morbidity after in vitro fertilization (IVF) is due to multiple pregnancy; however, even singleton infants are at an increased risk for adverse outcomes. We have summarized data that evaluates adverse outcomes in IVF infants and recent attempts to delineate the underlying causes of this risk. We submit that practitioners of reproductive medicine should remain at the forefront of this investigation.

Assisted reproduction for the validation of gestational age assessment methods

Despite major achievements in medicine, preterm birth (PTB) remains a leading cause of infant morbidity and mortality, worldwide. Research efforts have been devoted towards a better understanding of the multifactorial aetiology of PTB and its subtypes, with the purpose of prevention and control. The availability of valid and reliable gestational age data is a prerequisite for PTB classification. Pregnancies conceived through assisted reproduction treatments provide an opportunity for the exact determination of gestational age using date of delivery and dates of fertilization or implantation. The purpose of this review article is to evaluate the current evidence for or against the various methods that can be applied to measure gestational age, namely the first day of the last menstrual period, ultrasound before 20 weeks of gestation and post-natal assessments, and to propose the use of assisted reproduction treatments populations for further validation of these methods.

Effect of the method of conception and embryo transfer procedure on mid-gestation placenta and fetal development in an IVF mouse model

BACKGROUND

Abnormal placentation is a potential mechanism to explain the increased incidence of low birthweight observed after IVF. This study evaluates, in a mouse model, whether the method of conception and embryo transfer affect placentation and fetal development.

METHODS

IVF blastocysts (CF1 x B6D2F1/J) were cultured in Whitten's medium (IVF(WM), n = 55) or K modified simplex optimized medium with amino acids (IVF(KAA), n = 56). Embryos were transferred to the uteri of pseudo-pregnant recipients. Two control groups were created: unmanipulated embryos produced by natural mating (in vivo group, n = 64) and embryos produced by natural mating that were flushed from uterus and immediately transferred to pseudo-pregnant recipients (flushed blastocysts, FB group, n = 57). At gestation age 12.5 days, implantation sites were collected and fixed; fetuses and placentas were weighed and their developmental stage (DS) evaluated. Placental areas and vascular volume fractions were calculated; parametric statistics were applied as appropriate.

RESULTS

IVF fetuses showed a modest but significant delay in development compared with FB mice (P < 0.05). In addition, IVF conceptuses were consistently smaller than FB (P < 0.05). Importantly, these differences persisted when analyzing fetuses of similar DS. The placenta/fetus ratio was larger in the IVF group (IVF(WM) 0.95; IVF(KAA) = 0.90) than the FB group (0.72) (P < 0.05 for all comparisons). Gross morphology of the placenta and ratio labyrinth/fetal area were equivalent in the IVF and FB groups, as were percentage of fetal blood vessels, maternal blood spaces and trophoblastic components.

CONCLUSIONS

In vitro embryo culture affects fetal and placental development; this could explain the lower birthweight in IVF offspring.

The impact of ovarian stimulation for IVF on the developing embryo

The use of assisted reproductive technologies (ART) has been increasing over the past three decades, and, in developed countries, ART account for 1-3% of annual births. In an attempt to compensate for inefficiencies in IVF procedures, patients undergo ovarian stimulation using high doses of exogenous gonadotrophins to allow retrieval of multiple oocytes in a single cycle. Although ovarian stimulation has an important role in ART, it may also have detrimental effects on oogenesis, embryo quality, endometrial receptivity and perinatal outcomes. In this review, we consider the evidence for these effects and address possible underlying mechanisms. We conclude that such mechanisms are still poorly understood, and further knowledge is needed in order to increase the safety of ovarian stimulation and to reduce potential effects on embryo development and implantation, which will ultimately be translated into increased pregnancy rates and healthy offspring.

A comprehensive assessment of outcomes in pregnancies conceived by in vitro fertilization/intracytoplasmic sperm injection

OBJECTIVE

To assess the association between in vitro fertilization (IVF) with or without intracytoplasmic sperm injection (ICSI) and adverse birth outcomes.

STUDY DESIGN

Retrospective cohort study involved IVF/ICSI patients who were treated in the Ottawa Fertility Centre from 1996 to 2005 with a viable pregnancy (>20 weeks of gestation) and mothers who conceived naturally.

RESULTS

Eleven of the 1044 infants conceived with IVF/ICSI (1.1%) and 7 of the 1910 naturally conceived infants (0.4%) had congenital heart defects (P<0.01). Five of the 138 infants (3.6%) born to mothers with a body mass index>30 and conceived by IVF/ICSI had congenital heart defects, compared with none in the 240 infants born to mothers with a body mass index>30 and conceived naturally (P<0.01).

CONCLUSION

Infants conceived with use of IVF/ICSI have three times as high a risk of a congenital heart defect as naturally conceived infants.

The Groningen ART cohort study: ovarian hyperstimulation and the in vitro procedure do not affect neurological outcome in infancy

BACKGROUND

Due to the growing number of children born following assisted reproduction technology, even subtle changes in the children's health and development are of importance to society at large. The aim of the present study was to evaluate the specific effects of ovarian hyperstimulation and the in vitro procedure on neurological outcome in 4-18-month-old children.

METHODS

In this prospective assessor-blinded cohort study, we included singletons born following controlled ovarian hyperstimulation in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) (COH-IVF; n = 68) or modified natural cycle-IVF/ICSI (MNC-IVF; n = 57) or naturally conceived singletons of subfertile couples (NC; n = 90). Children were assessed with standardized, age-specific and sensitive neurological assessments (TINE and Hempel assessment) at 4, 10 and 18 months. Neurological examination resulted in a neurological optimality score (NOS), a fluency score and a clinical neurological classification. Fluency of movements is easily affected by neurological dysfunction and is therefore a sensitive measure for minimal changes in neuromotor development.

RESULTS

The NOS and the fluency score were similar in COH-IVF, MNC-IVF and NC children. None of the children showed major neurological dysfunction and rates of minor neurological dysfunction at the three ages were not different between the three conception groups.

CONCLUSIONS

We found no effects of ovarian hyperstimulation or the in vitro procedure itself on neurological outcome in children aged 4-18 months. The findings of our study are reassuring, nevertheless it should be kept in mind that subtle neurodevelopmental disorders may emerge when children grow older. Continuation of follow-up in older and larger groups of children is therefore still needed.

Twins born following assisted reproductive technology: perinatal outcome and admission to hospital

BACKGROUND

Compared with spontaneously conceived (SC) singletons, adverse perinatal outcome, neonatal intensive care unit (NICU) admission and hospital admission in infancy are more common in those born following Assisted Reproductive Technology (ART). Similar comparisons for twins have shown conflicting results.

METHODS

We investigated perinatal outcome and hospital admission during the first 3 years of life for all twin children born in Western Australia between 1994 and 2000 [700 ART, 4097 SC].

RESULTS

ART twins had a greater risk of adverse perinatal outcome including preterm birth, low birthweight and death compared with SC twins of unlike-sex. In their first year of life, ART twins had a longer birth admission; were 60% more likely to be admitted to a NICU; and had a higher risk of hospital admission. The increased risk of hospital admission continued in the second and third year but was not statistically significant in the third year.

CONCLUSIONS

Couples undertaking ART should be aware that in addition to the known increased perinatal risks associated with a twin birth, ART twins are more likely than SC twins to be admitted to a NICU and hospitalized in the first 3 years of life.

Mild ovarian stimulation for IVF

BACKGROUND

Mild ovarian stimulation for in vitro fertilization (IVF) aims to achieve cost-effective, patient-friendly regimens which optimize the balance between outcomes and risks of treatment.

METHODS

Pubmed and Medline were searched up to end of January 2008 for papers on ovarian stimulation protocols for IVF. Additionally, references to related studies were selected wherever possible.

RESULTS

Studies show that mild interference with the decrease in follicle-stimulating hormone levels in the mid-follicular phase was sufficient to override the selection of a single dominant follicle. Gonadotrophin-releasing hormone antagonists compared with agonists reduce length and dosage of gonadotrophin treatment without a significant reduction in the probability of live birth (OR 0.86, 95% CI 0.72-1.02). Mild ovarian stimulation may be achieved with limited gonadotrophins or with alternatives such as anti-estrogens or aromatase inhibitors. Another option is luteinizing hormone or human chorionic gonadotrophin administration during the late follicular phase. Studies regarding these approaches are discussed individually; small sample size of single studies along with heterogeneity in patient inclusion criteria as well as outcomes analysed does not allow a meta-analysis to be performed. Additionally, the implications of mild ovarian stimulation for embryo quality, endometrial receptivity, cost and the psychological impact of IVF treatment are discussed.

CONCLUSIONS

Evidence in favour of mild ovarian stimulation for IVF is accumulating in recent literature. However, further, sufficiently powered prospective studies applying novel mild treatment regimens are required and structured reporting of the incidence and severity of complications, the number of treatment days, medication used, cost, patient discomfort and number of patient drop-outs in studies on IVF is encouraged.

Ovarian stimulation for IVF has no quantitative association with birthweight: a registry study

BACKGROUND

Singleton children born after IVF are of lower birthweight compared with their naturally conceived peers. It has been hypothesized that ovarian stimulation might be associated with low birthweight in children born after IVF. The aim of the present study was to explore whether or not a dose relationship exists between ovarian stimulation and birthweight in singletons born after ovarian stimulation for IVF.

METHODS

Using a national IVF registry database with a coverage of 65-70%, parental demographic variables, treatment cycle variables and neonatal variables were retrieved from all IVF treatment cycles in women between 25 and 35 years of age in which gonadotrophins were used for ovarian stimulation and a fresh embryo transfer resulting in singleton live birth was performed. Birthweight was standardized as a z-score, adjusting for gestational week at delivery and fetal sex, using data from a large reference population. Multivariate regression analysis was used to investigate the association between the dependent variable z-score and the independent predictor variables maternal age (years), maternal weight (kg), maternal height (cm), maternal body mass index (BMI) (kg/m(2)), duration of infertility (years), number of embryos transferred (n), duration of stimulation (days), consumption of gonadotrophins (ampoules) and number of oocytes retrieved (n).

RESULTS

Data retrieval yielded 32,416 singleton live births after IVF, with a mean (+/-SD) z-score of -0.25 (+/-1.0) and -0.23 (+/-1.0) for male and female neonates, respectively. Regression analysis indicated that maternal weight, maternal height, duration of infertility and the number of embryos transferred were statistically significant determinants of the birthweight of singletons after ovarian stimulation IVF. Parameters of ovarian stimulation (duration of stimulation, consumption of gonadotrophins, number of oocytes retrieved), maternal BMI and maternal age did not significantly predict birthweight.

CONCLUSIONS

Features reflecting ovarian stimulation do not correlate with birthweight. Therefore, ovarian stimulation is unlikely to be a factor affecting birthweight of IVF pregnancies.

Does confined placental mosaicism account for adverse perinatal outcomes in IVF pregnancies?

BACKGROUND

IVF singletons have poorer perinatal outcomes than singletons from spontaneous conceptions. This may be due to the influence of ovarian stimulation on the chromosomal constitution of the embryos which could be translated into localized chromosomal anomalies in the placenta. The aim of this study was to compare the incidence of confined placental mosaicism (CPM) in IVF/ICSI pregnancies and spontaneous conceptions.

METHODS

We conducted a multi-centre retrospective analysis of karyotype results obtained by chorionic villus sampling (CVS), performed due to advanced maternal age (>or=36 years at 18 weeks of gestation), in the Netherlands between 1995 and 2005.

RESULTS

From a total of 322 246 pregnancies, 20 885 CVS results were analysed: 235 in the IVF/ICSI group and 20 650 in the control group. The mean age of women in both groups was 38.4 years (mean difference -0.08, 95% CI -0.35 to 0.18). Data relating to the fetal karyotype were missing in 143 cases in the control group. When taking into account missing data, the incidence of CPM was lower in the IVF-ICSI group than in the control group, 1.3% versus 2.2% (odds ratio 0.59, 95% CI 0.19-1.85), whereas the incidence of fetal chromosomal anomalies was increased 4.3% versus 2.4% (odds ratio 1.81, 95% CI 0.95-3.42). Neither differences were statistically significant.

CONCLUSIONS

The incidence of CPM is not increased in IVF/ICSI pregnancies compared with spontaneous conceptions. CPM probably does not account for the adverse perinatal outcomes following IVF/ICSI.

Infertility, infertility treatment, and fetal growth restriction

OBJECTIVE

To examine the association between infertility, with or without treatment, and fetal growth, as well as perinatal and infant mortality.

METHODS

From the Danish National Birth Cohort (1997-2003), we identified 51,041 singletons born of fertile couples (time to pregnancy 12 months or less), 5,787 born of infertile couples conceiving naturally (time to pregnancy more than 12 months), and 4,317 born after treatment. We defined small for gestational age (SGA) as the lowest 5% of birth weight by sex and gestational age.

RESULTS

Crude estimates suggested an increased risk of perinatal mortality and SGA among infertile couples (treated and untreated), but the odds ratios (ORs) of perinatal mortality among infertile couples were attenuated after adjustment for maternal age and body mass index (1.32, 95% confidence interval [CI] 0.95-1.84 among untreated and 1.26, 95% CI 0.86-1.85 among treated couples). The elevated risk of SGA among infertile couples persisted after adjustment for maternal age, parity, and smoking (OR 1.24, 95% CI 1.10-1.40 among untreated, and OR 1.40, 95% CI 1.23-1.60 among treated). The risk of SGA increased with time to pregnancy, and a longer time to pregnancy was associated with a small reduction in birth weight across the whole distribution.

CONCLUSION

The increased risk of SGA observed among infertile couples with or without infertility treatment suggests that infertility may be a risk factor for intrauterine growth restriction. Treatment per se may have little effect on fetal growth. A small-to-moderate increased risk of perinatal mortality in infertile couples cannot be ruled out due to the small number of cases.

LEVEL OF EVIDENCE

II.

Perinatal outcome, health, growth, and medical care utilization of 5- to 8-year-old intracytoplasmic sperm injection singletons

OBJECTIVE

To evaluate short- and long-term health in intracytoplasmic sperm injection (ICSI) singletons.

DESIGN

Follow-up study.

SETTING

University medical center, assessments between March 2004 and May 2005.

PATIENT(S)

Singletons born between June 1996 and December 1999 after ICSI in the Leiden University Medical Center laboratory were compared with matched singletons born after IVF and natural conception.

INTERVENTION(S)

Mode of conception.

MAIN OUTCOME MEASURE(S)

An examiner blinded to the conception mode of the child assessed congenital malformations and growth. Information on pregnancy, perinatal period, birth defects, general health, and medical consumption was obtained through questionnaires.

RESULT(S)

Outcomes of children conceived by ICSI and IVF (n = 81/81, preterm infants excluded) were comparable or even more positive for ICSI. Perinatal outcomes were poorer after ICSI than natural conception: prematurity: P=.014; low birth weight: odds ratio = 7.4, 95% confidence interval (CI) [0.9; 62.5]; mean birth weight: Delta = 186 g, 95% CI [21; 351]. The ICSI mothers had more pregnancy complications (n = 33 vs. 18) and in-hospital deliveries (prevalence ratio 1.36, 95% CI 1.17; 1.48). No further differences were found between ICSI and natural conception children on congenital malformations, health, growth, and medical consumption (n = 87/85, preterm infants included).

CONCLUSION(S)

No adverse health outcomes were identified in ICSI singletons up to age 5-8 years compared to IVF and natural conception singletons, besides poorer perinatal outcomes after ICSI versus natural conception.