The risk of birth defects after assisted reproduction

Trends in the incidence of major birth defects after assisted reproductive technologies in Lombardy Region, Northern Italy

PURPOSE

The incidence of birth defects is increased in children born after assisted reproductive technologies (ART). However, changes in ART over time could influence this incidence. To investigate this issue, we present the frequency and trends of birth defects in ART and natural pregnancies in Lombardy, Northern Italy, during the period 2014-2020.

METHODS

This is a population-based study using automated system of healthcare utilization (HCU) databases. ART pregnancies included only those obtained with conventional IVF or ICSI. After identifying the total number of deliveries, the rate of newborns with birth defects was compared between natural and ART pregnancies. A logistic regression model was used to calculate the adjusted odd ratio (OR). Analyses were repeated for every calendar year.

RESULTS

Overall, 508,421 deliveries were identified, of which 14,067 (2.8%) were achieved after IVF-ICSI. A decreasing trend in birth defects over time was highlighted. The adjusted OR dropped from 1.40 (95%CI: 1.03-1.91) in 2014 to 0.92 (95%CI: 0.69-1.22) in 2020. During the study period, a significant reduction in multiple pregnancy and in the ratio of ICSI to conventional IVF was also observed, explaining at least in part the positive trend observed for birth defects.

CONCLUSION

The increased risk of birth defects in children born after IVF-ICSI is not steady over time. A decline of this risk emerged in our region. Policy changes in ART may explain this beneficial effect.

Trends in Dizygotic and Monozygotic Spontaneous Twin Births During the Period 2007-2017 in Lombardy, Northern Italy: A Population-Based Study

In this study, we analyzed the estimated frequency of monozygotic (MZ) and dizygotic (DZ) spontaneous twins in Lombardy during the period 2007-2017. This is a population-based study using the regional healthcare utilization databases of the Lombardy Region. The total number of spontaneous twin deliveries, in separate strata of like and unlike sex, was obtained. Moreover, estimates of DZ and MZ twin births were calculated using Weinberg's method. The standardized rates (SRs), adjusted for maternal age, of DZ and MZ twin births were computed according to calendar period. The twinning rates were calculated among strata of parity and maternal age. Finally, DZ:MZ ratio was calculated. Among the 734,278 spontaneous deliveries, 9176 (12.5 out of 1000 births) couples of twins were identified. In the three periods considered (i.e. 2007-2010, 2011-2014 and 2015-2017), no trend in the SRs of MZ twins was observed, respectively 0.41 (95% CI [0.40, 0.43]), 0.43 (95% CI [0.42, 0.45]) and 0.43 (95% CI[0.42, 0.45]). Differently, a slightly decreasing trend was observed in DZ twins SRs, respectively 0.87 (95% CI [0.84, 0.89]), 0.81 (95% CI [0.79, 0.83]), and 0.78 (95% CI [0.76, 0.80]). As concerns parity and maternal age, the rate of DZ twin births was consistently higher in nulliparae women aged 35 years or more. In our cohort, despite the increase of maternal age, a decline of spontaneous twin births emerged, especially due to the downward trend of DZ twins.

Risk of mayor and minor birth defects in children conceived by assisted reproductive technology (IVF/ICSI): A prospective controlled cohort study

INTRODUCTION

About 0.2-6.1% of newborns in the developed world have been conceived by assisted reproductive techniques (ART). Higher rate of major and minor malformations have been described in this population, but the multiple possible confounders associated make it difficult to establish a direct causal relationship and the specific factors involved.

MATERIAL AND METHODS

To determine the risk of these malformations in our population, a collaborative prospective controlled cohort study was designed. We collected the specific ART-data related to the clinical gestation of women treated in a period of 2 years in the Reproduction Unit from a Spanish public tertiary-level hospital. 231 out of 267 newborns of these gestation (88%) participated in the study and were assessed by a pediatrician with expertise in Clinical Genetics and Dysmorphology at 12-20 and 26-40 months of age. At the same time a controlled group of children naturally conceived (NC) was selected according to the following criteria: the next NC newborn belonging to the same group of maternal and gestational age, and type of gestation (single or multiple). 230 controls were chosen and 208 participated in the study (90%).

RESULTS

Major malformations were presented in 7.8% of the ART-children and 7.2% of the controls, without founding statistically differences between groups. However, differences were found in the risk of some minor malformations such as capillary malformations and pigmentary lesions, higher in the ART-group. A recurrent pattern of craneofacial anomalies was also unexpectedly detected.

CONCLUSIONS

In spite of the high rate of major congenital malformations detected, there were no differences between groups. Thus, our results suggest that ART may affect the normal embryonic development but in a milder way than other confounding factors do. The facial phenotype identified has not previously been described, either the higher risk of capillary malformations and pigmentary lesions. More studies are needed to confirm this association.

Effects of the early phase of the COVID-19 pandemic on natural and ART-mediated birth rates in Lombardy Region, Northern Italy

Research question

What effects did the early phase of the COVID-19 pandemic have on natural and assisted reproductive technology (ART)-mediated birth rates?

Design

Regional registries were consulted with permission from the Health Authorities of Lombardy Region, Northern Italy, an area particularly affected by the early phase of the epidemic. Deliveries occurring in the area between 1 January 2019 and 31 December 2020 from women beneficiaries of the National Health System and resident in Lombardy were identified. Comparisons mainly focused on December 2020, when women who conceived after 8 March (the start of the stringent lockdown imposed by the authorities) were expected to deliver.

Results

When comparing the periods January to November in 2019 and 2020, a 5.1% reduction of monthly general birth rate (from 5732 in 2019 to 5438 in 2020) was observed. The contribution of ART births was similar in 2019 and 2020, being 4.4% and 4.5%, respectively. In December 2020, a notable drop in natural (–17.8%), ART-mediated (–86.6%) and overall (–21.0%) births was observed compared with December 2019. After adjusting for the expected 5.1% reduction, the inferred effect of the COVID-19 crisis corresponded to a 16.7% reduction in birth rate, of which 76% was related to natural (707 births) and 24% to ART (218 births) conceptions.

Conclusions

This is the first study providing population-based evidence on the effects of COVID-19 and its related stringent restrictions on birth rates. The birth rate was dramatically reduced following the critical period, and the closure of ART centres played only a marginal role (24%) in the overall detrimental effect.

[Risk of mayor and minor birth defects in children conceived by assisted reproductive technology (IVF/ICSI): A prospective controlled cohort study]

INTRODUCTION

About 0.2-6.1% of newborns in the developed world have been conceived by assisted reproductive techniques (ART). Higher rate of major and minor malformations have been described in this population, but the multiple possible confounders associated, make it difficult to establish a direct causal relationship, and the specific factors involved.

MATERIAL AND METHODS

To determine the risk of these malformations in our population, a collaborative prospective controlled cohort study was designed. We collected the specific ART-data related to the clinical gestation of women treated in a period of 2 years in the Reproduction Unit from a Spanish public tertiary-level hospital. 231 out of 267 newborns of these gestation (88%) were exhausted assessed by a Clinical Geneticist expertise in Dysmorphology at 12-20 and 26-40 months of age. At the same time a controlled group of children naturally conceived (NC) was selected according to the following criteria: the next NC newborn belonging to the same group of maternal and gestational age, and type of gestation (single or multiple). 230 controls were chosen and 208 participated in the study (90%).

RESULTS

Major malformations were presented in 7.8% of the ART-children and 7.2% of the controls, without founding statistically differences between groups. However, differences were found in the risk of some minor malformations such as capillary malformations and pigmentary lesions, higher in the ART-group. A recurrent pattern of craneofacial anomalies was also unexpectedly detected.

CONCLUSIONS

In spite of the high rate of major congenital malformations detected, there were no differences between groups. Thus, our results suggest that ART may affect the normal embryonic development but in a milder way than other confounding factors do. The facial phenotype identified has not previously, either the higher risk of capillary malformations and pigmentary lesions. More studies are needed to confirm this association.

Trend of medically induced monozygotic twin deliveries according to age, parity, and type of assisted reproductive technique during the period 2007-2017 in Lombardy Region, Northern Italy: a population-based study

Purpose

The risk of monozygotic (MZT) twinning is increased in pregnancies after assisted reproductive technologies (ART). However, determinants remain poorly understood. To shed more light on this issue, we analyzed the estimated frequency of MZT twins from ART in Lombardy, Northern Italy, during the period 2007–2017.

Methods

This is a population-based study using regional healthcare databases of Lombardy Region. After having detected the total number of deliveries of sex-concordant and sex-discordant twins from ART, we calculated MZT rate using Weinberg’s method. Standardized ratios (SRs) and corresponding 95% confidence intervals (CI) of MZT deliveries, adjusted for maternal age, were computed according to calendar period, parity, and type of ART.

Results

On the whole, 19,130 deliveries from ART were identified, of which 3,446 were twins. The estimated rate of MZT births among ART pregnancies was higher but decreased over time (p-value = 0.03); the SRs being 1.33 (95% CI: 1.18–1.51), 0.96 (95% CI: 0.83–1.11), and 0.92 (95% CI: 0.79–1.07) for the periods 2007–2010, 2011–2014, and 2015–2017, respectively. The SRs of MZT among women undergoing first-level techniques, conventional in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI) were 0.47 (95% CI: 0.38–0.57), 1.02 (95% CI: 0.88–1.17), and 1.43 (95% CI: 1.27–1.61) (p-value < 0.0001). The ratio of MZT births was significantly higher in women younger than 35 years (p-value < 0.0001) and slightly higher among nulliparae (p-value < 0.0001).

Conclusion

Despite a reduction of MZT rate from ART over the time, the risk remains higher among ART pregnancies rather than natural ones. Younger women and women undergoing ICSI showed the highest risk of all.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10815-021-02268-0.

The association between in vitro fertilization and intracytoplasmic sperm injection treatment and the risk of congenital heart defects

OBJECTIVE

Assisted reproductive technology (ART), an effective treatment modality for infertility, is associated with a higher prevalence of congenital anomalies such as congenital heart defects (CHDs). The present study aimed to evaluate data linking CHDs in infants to pregnancies resulting from in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI).

METHODS

In this study, we conducted a systematic literature search on CHDs in infants following IVF/ICSI in Google Scholar, Embase, Scopus, MEDLINE, and PubMed databases from inception to February 2020. The search strategy used combinations of search keywords that included assisted reproductive technology/ART, in vitro fertilization/IVF, intracytoplasmic sperm injection/ICSI, birth defect, congenital malformation, and congenital heart defects.

RESULTS

Fifty-six studies fulfilled the inclusion criteria and were selected in the current systematic review, which assessed the association between ART and the risk of CHDs.

CONCLUSION

Children conceived by IVF/ICSI manifested an increased risk of CHDs compared with spontaneously conceived children. Further studies are needed to assess the long-term cardiovascular safety of these techniques, which is important for the counseling of patients before the use of ART.

Birth defects surveillance after assisted reproductive technology in Beijing: a whole of population-based cohort study

OBJECTIVES

To compare the differences in the prevalence of birth defects among offspring conceived by assisted reproductive technology (ART) and conceived spontaneously (non-ART), and assess the contribution of ART to birth defects.

DESIGN

A population-based retrospective cohort study.

SETTING

Beijing.

PARTICIPANTS

Pregnant women whose expected date of childbirth was verified as occurring between October 2014 and September 2015, and were registered on the Beijing Maternal and Child Health Information Network System, were the recorded pregnancy outcomes. 2699 ART offspring and 191 368 non-ART offspring (live births, stillbirths and medical terminations) were included in our study.

INTERVENTIONS

None.

OUTCOME MEASURES

Risk ratios (RR) for birth defects were calculated among ART conceptions and non-ART conceptions with confounding factors by using logistic regression models.

RESULTS

194 067 offspring were included in the present study, and 2699 (1.4%) were conceived using ART. Among all the births, the prevalence of any birth defect in the ART offspring (5.5%) was significantly higher than in the non-ART offspring (3.8%) (crude RR, 1.49, 95% CI 1.26 to 1.76). After adjusting for confounding factors, ART use was still associated with an increased risk of any birth defect (5.4% vs 3.5% in ART and non-ART group, adjusted RR (aRR), 1.43, 95% CI 1.08 to 1.90), especially for chromosomal abnormalities (0.5% vs 0.2% in ART and non-ART group, aRR, 3.11, 95% CI 1.28 to 7.58), in singleton births to mothers <35 years. Circulatory system malformations and musculoskeletal system malformations were observed to have a non-significant increase in offspring conceived by ART. However, the associations between ART and birth defects were not detected in multiple births or mothers ≥35 years.

CONCLUSIONS

This study confirmed a small but significant association between ART and birth defects. However, the risk tends to be non-significant under the conditions of advanced maternal age or multiple pregnancies.

Assessing the cognitive and behavioral development of 3-year-old children born from fathers with severe male infertility

BACKGROUND

Despite the large number of babies born worldwide following intracytoplasmic sperm injection, concerns about the procedure's safety still exist owing to the use of suboptimal spermatozoa. Thus, follow-up of children conceived via intracytoplasmic sperm injection is highly recommended. We propose the use of parent-administered questionnaires to monitor the development of offspring conceived via intracytoplasmic sperm injection.

OBJECTIVE

This study aimed to determine whether male infertility treatment affects offspring development.

STUDY DESIGN

We compared obstetrical and neonatal outcomes and physical and psychological development of toddlers conceived via in vitro fertilization and intracytoplasmic sperm injection. Once newborns reached 3 years of age, participating patients were sent a set of parent-administered questionnaires, including the Ages and Stages Questionnaires; Prescreening Developmental Questionnaire 2; Peabody Developmental Motor Scales, Second Edition; Social Skills Rating System; Parenting Stress Index, Third Edition; and Child Behavior Checklist for Ages 2-3. Child development was measured by the Ages and Stages Questionnaires; Prescreening Developmental Questionnaire 2; and Peabody Developmental Motor Scales, Second Edition, questionnaires, whereas Social Skills Rating System; Parenting Stress Index, Third Edition; and Child Behavior Checklist for Ages 2-3 questionnaires were used to measure child behavior. The child's developmental or behavioral outcome was considered "abnormal" when he or she scored below average in ≥2 questionnaires from the respective category. We also conducted subanalyses to assess the effects of male genomic integrity, DNA fragmentation, chemical exposure, utilization of surgically retrieved spermatozoa, and extended embryo culture to determine the development of a child conceived via intracytoplasmic sperm injection.

RESULTS

A total of 12,306 couples met the inclusion criteria for this study; 1914 of 7433 patients (25.8%) who underwent intracytoplasmic sperm injection and 451 of 4873 patients (9.3%) who underwent in vitro fertilization returned the questionnaires. Our comparison of obstetrical outcomes between the 2 groups did not reveal any significant differences in the mode of delivery distribution, with most mothers having uncomplicated vaginal deliveries. Furthermore, gender distribution, gestational ages, and birthweights were also comparable between children conceived via intracytoplasmic sperm injection and in vitro fertilization. However, children conceived via in vitro fertilization displayed impaired developmental characteristics compared with the intracytoplasmic sperm injection-conceived cohort (adjusted odds ratio, 0.72; 95% confidence interval, 0.5-0.9; P=.0004). There was no difference in child behavior. Furthermore, 3 cases of autism were reported, 1 case from the in vitro fertilization group and 2 from the intracytoplasmic sperm injection group, all conceived from couples with an older male partner. Ages and Stages Questionnaires outcomes were also compared for the offspring conceived via in vitro fertilization and intracytoplasmic sperm injection by gender; however, no significant differences were observed. In addition, 5 separate subanalyses were then conducted exclusively for the intracytoplasmic sperm injection-conceived group. Levels of spermatogenic failure, DNA fragmentation, and chemical exposure did not significantly affect offspring development. Interestingly, although the length of embryo culture did not seem to influence child development, the abnormal behavior rate was significantly higher in children from the day 3 embryo transfer cohort (adjusted odds ratio, 0.4; 95% confidence interval, 0.05-0.34; P=.04). Children conceived via intracytoplasmic sperm injection from ejaculated spermatozoa displayed impaired developmental and behavioral characteristics compared with toddlers conceived from surgically retrieved specimens (adjusted odds ratio, 4.9; 95% confidence interval, 1.2-20.7; P=.05).

CONCLUSION

Most children conceived via intracytoplasmic sperm injection and in vitro fertilization are developing well without significant delays. Although the development of a child conceived via intracytoplasmic sperm injection was not affected by most of the variables assessed, those conceived from surgically retrieved spermatozoa were at a considerably lower risk of abnormal developmental and abnormal behavioral characteristics than offspring conceived from ejaculated specimens. However, given the small numbers of respondents available for many subgroups of interest, further studies of outcomes of children born from fathers with severe male factor infertility are warranted.

Assisted reproductive technology and birth defects in a Chinese birth cohort study

Background

It has been consistently shown in several meta-analyses that infants born after ART have an excess of birth defects compared with those after spontaneous conception, however, the prevalence of birth defects among ART offspring in China is incompletely studied. Moreover, it is unclear to what extent the risk of birth defects is associated with parental infertility characteristics, specific ART procedures and twinning.

Methods

In the prospective cohort study, we included women who participated in the cohort, and had pregnancies of at least 20 gestational weeks between August 2016 and May 2019, and followed them until their children reached 1 year of age. Exposures of interest were ART, as well as infertility-related characteristics, certain ART procedures and specific medication usage. The primary outcome was birth defects including both major and minor defects, which we analysed with logistic generalized estimating equations to investigate the association with ART and certain ART characteristics.

Findings

A total of 1,825 women with ART-pregnancy and 3,483 women with spontaneous-pregnancy were included in the analysis. The prevalence of any defects was significantly higher among ART-births than their non-ART counterparts at each follow-up, specifically at prenatal screening (2•2% vs. 1•2%), at delivery (4•9% vs. 2•9%), at 6 months (10•4% vs. 5•3%) and 1 year of age (13•9% vs. 7•0%), and the associations between ART and increased risk of birth defects at each follow-up were similarly robust. Among ART-births, GnRH antagonist regimen for ovulation induction in women was associated with an increased risk of birth defects in their offspring after taking into account potential influencing factors (Multivariable model: adjusted risk ratio [aRR] 1•47, 1•04–2•07). Additionally, mediation through twinning accounted for 31•1% of the risk of ART-associated birth defects.

Interpretation

The results suggest that ART confers an increased risk for birth defects in offspring. The risk is partly attributable to infertility characteristics, certain ovulation induction regimen, and to some extent mediated by twinning. Our findings highlight the importance of long-term follow-up of children conceived via ART for health conditions.

Funding

National Key Research and Development Program of China, National Natural Science Foundation of China and Natural Science Foundation of Jiangsu Province.

Maternal occupational exposure to chemicals in the textile factory during pregnancy is associated with a higher risk of polydactyly in the offspring

Background: The number of children with polydactyly seen in our clinic is increasing. In addition to genetic factors, an influence of environmental effects during pregnancy is becoming increasingly apparent; however, epidemiological data on these effects are lacking.Methods: This hospital-based, case-control study enrolled 143 patients with polydactyly and 286 control patients with no genetic diseases, to evaluate the association between maternal exposure to a textile factory environment during pregnancy and the likelihood of giving birth to a child with polydactyly.Results: Maternal exposure to a textile factory environment during pregnancy was associated with an increased risk of giving birth to a child with polydactyly (exposure to textile factory environment: unadjusted odds ratio (OR) = 3.31, 95% confidence interval (CI) = 1.75-6.27, p = .0002; work seniority of exposed occupation: unadjusted OR 1.28, 95% CI = 1.13-1.47, p = .0002). Covariate screening indicated that certain risk factors (family monthly income per capita, mother's emotional state during pregnancy, colporrhagia, passive smoking, smoking, and history of consanguineous marriage) were potential confounding factors. After adjusting for these variables, the OR of exposure to a textile factory environment remained significant (exposure to textile factory environment: adjusted OR = 3.08, 95% CI = 1.32-7.19, p = .0094; work seniority of exposed occupation: adjusted OR = 1.58, 95% CI = 1.20-2.08, p = .0010). The risk of polydactyly increased with the number of years of employment.Conclusions: Maternal exposure to a textile factory environment appears to be a risk factor for polydactyly in newborns.

Pregnancy and offspring outcomes after artificial insemination with donor sperm: A retrospective analysis of 1805 treatment cycles performed in Northwest China

Artificial insemination with donor sperm (AID) is a widely used procedure, but its success rate in China remains uncharacterized. This study investigated the factors associated with occurrence of clinical pregnancy and live birth and evaluated the birth outcomes in the offspring after AID in Northwest China.We retrospectively reviewed the results of 1805 AID courses in 1046 couples during 2006-2015. We analyzed whether the number of AID cycles, age of the female patient, and number of sperm with progressive motility were associated with the occurrence of clinical pregnancy and live birth. We also evaluated the birth outcomes in the offspring.Among the 1805 cycles, 447 (24.8%) resulted in clinical pregnancy and 384 (21.3%) resulted in a live birth. Miscarriage occurred in 57 of the 447 cases of clinical pregnancy (12.8%). The proportion of cycles resulting in a live birth decreased significantly with age (P < .001). The proportion of clinical pregnancies that resulted in miscarriage increased with age (P < .001). Cumulative pregnancy rate (the proportion of patients achieving a clinical pregnancy) increased progressively from 23.0% after 1 cycle to 42.7% after ≥5 cycles. The proportion of cycles resulting in clinical pregnancy did not vary with the total number of sperm with progressive motility administered per cycle. Multivariate logistic regression analysis revealed that superovulation treatment and number of cycles were factors associated with clinical pregnancy, while superovulation treatment, number of cycles, and patient age were factors associated with live birth. Among the 384 live births, only one case (0.3%) of birth defect (hexadactyly) was observed.In patients undergoing AID, clinical pregnancy is associated with superovulation treatment and number of cycles, and live birth is associated with superovulation treatment, number of cycles, and patient age. The risk of birth defects in the offspring after AID is low.

Comparison of neonatal outcomes and live-birth defects after progestin-primed ovarian stimulation versus conventional ovarian stimulation for in vitro fertilization: A large retrospective cohort study

Progestin-primed ovarian stimulation (PPOS) is a new ovarian stimulation regimen for in vitro fertilization (IVF), with the advantages of an oral administration route and more control over preovulatory luteinizing hormone (LH) levels. Assessing the safety of this novel regimen is an important premise for its routine practice.We conducted a large retrospective cohort study for infants born between August 2014 and April 2017 from IVF and embryo transfer cycles after either PPOS and the conventional gonadotropin-releasing hormone-agonist (GnRH-a) short protocol at our center. Around 1589 live-born infants were finally enrolled, corresponding to 1258 frozen-thawed (FET) cycles, which led to 855 live-born infants from PPOS (659 FET cycles) and 734 live-born infants from the short protocol (599 FET cycles).Birth characteristics regarding gestational age, birth weight and length, infant sex, and early neonatal death were comparable between the 2 groups. The incidence of live-birth defects in the PPOS group (1.52%) was similar to that in the short protocol group (1.63%) and was not statistically significant. For birth defects, the risk significantly increased for multiple births, and the adjusted odds ratio was 3.14 (95% confidence interval [CI]: 1.25-7.88). No associations were found between congenital birth defects and maternal age, body mass index (BMI), the duration of infertility, method of insemination, infant sex, embryo stage at transfer, the number of embryos transferred or ovarian stimulation regimen.Our study shows that the neonatal outcomes and risk of congenital malformations were similar between the PPOS and conventional GnRH-a short protocol. However, multiple pregnancy led to a higher likelihood of birth defects.

Congenital heart defects in IVF/ICSI pregnancy: systematic review and meta-analysis

OBJECTIVE

There is no consensus in current practice guidelines on whether conception by in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) techniques is an indication for performing a fetal echocardiogram. The aim of the study was to assess whether congenital heart defects (CHD) occur more often in pregnancies conceived after IVF/ICSI as compared with those conceived spontaneously.

METHODS

A systematic search for studies was conducted of PubMed/MEDLINE, EMBASE and Scopus from inception to September 2017. The search included the following medical subject heading (MeSH) terms alone or in different combinations: 'IVF', 'IVF/ICSI', 'ART pregnancy', 'assisted conception', 'birth defect', 'congenital heart defects' and 'congenital malformation or abnormalities'. Studies comparing neonatal incidence of CHD in pregnancies conceived after IVF/ICSI and those conceived spontaneously were included. Studies reporting on other types of assisted reproductive technology (ART) or lacking information concerning termination of pregnancy were excluded. Chromosomal abnormalities were excluded in all analyzed studies. A meta-analysis of selected cohort studies was conducted to estimate the pooled odds ratio (OR) with 95% CI using a random-effects model. Statistical heterogeneity among the studies was evaluated with the I² statistic and Q-test.

RESULTS

Forty-one studies were identified for review including six case-control and 35 cohort studies. Data of eight selected cohort studies were used for meta-analysis. A total of 25 856 children conceived from IVF/ICSI techniques and 287 995 children conceived spontaneously, involving both singleton and multiple gestations, were included in the analysis. Total CHD events were 337/25 856 (1.30%) and 1952/287 995 (0.68%) in the IVF/ICSI and spontaneous conception groups, respectively. The risk of CHD was significantly increased in the IVF/ICSI group as compared with the spontaneous conception group (pooled OR, 1.45; 95% CI, 1.20-1.76; P = 0.0001; I²  = 44%; P = 0.08). In the subgroup of singleton IVF pregnancies, a significant difference was also obtained (OR, 1.55; 95% CI, 1.21-1.99; P = 0.0005; I²  = 36%; P = 0.18) and also multiple confounding factors adjusted ORs showed statistical significance (pooled OR, 1.29; 95% CI, 1.03-1.60; P = 0.02; I²  = 0%; P = 0.43).

CONCLUSION

Fetuses conceived with IVF/ICSI methods are at an increased risk of developing CHD compared with those conceived spontaneously. However, this finding deserves further investigation due to heterogeneity of both ART procedures and cardiac defects. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Assisted Reproductive Technology and Birth Defects: Effects of Subfertility and Multiple Births

BACKGROUND

Assisted reproductive technology (ART) has been associated with birth defects, but the contributions of multiple births and underlying subfertility remain unclear. We evaluated the effects of subfertility and mediation by multiple births on associations between ART and nonchromosomal birth defects.

METHODS

We identified a retrospective cohort of Massachusetts live births and stillbirths from 2004 to 2010 among ART-exposed, ART-unexposed subfertile, and fertile mothers using linked information from fertility clinics, vital records, hospital discharges, and birth defects surveillance. Log-binomial regression was used to estimate prevalence ratios and 95% confidence intervals (CIs). Mediation analyses were performed to deconstruct the ART-birth defects association into the direct effect of ART, the indirect effect of multiple births, and the effect of ART-multiples interaction.

RESULTS

Of 17,829 ART-exposed births, 355 had a birth defect, compared with 162 of 9431 births to subfertile mothers and 6183 of 445,080 births to fertile mothers. The adjusted prevalence ratio was 1.5 (95% CI, 1.3-1.6) for ART and 1.3 (95% CI, 1.1-1.5) in subfertile compared with fertile deliveries. We observed elevated rates of several birth defects with ART, including tetralogy of Fallot and hypospadias. Subfertility and multiple births affect these associations, with multiple births explaining 36% of the relative effect of ART on nonchromosomal birth defects.

CONCLUSION

Although the risk of birth defects with ART is small, a substantial portion of the relative effect is mediated through multiple births, with subfertility contributing an important role. Future research is needed to determine the impact of newer techniques, such as single embryo transfer, on these risks. Birth Defects Research 109:1144-1153, 2017. © 2017 Wiley Periodicals, Inc.

The health outcomes of human offspring conceived by assisted reproductive technologies (ART)

Concerns have been raised about the health and development of children conceived by assisted reproductive technologies (ART) since 1978. Controversially, ART has been linked with adverse obstetric and perinatal outcomes, an increased risk of birth defects, cancers, and growth and development disorders. Emerging evidence suggests that ART treatment may also predispose individuals to an increased risk of chronic ageing related diseases such as obesity, type 2 diabetes and cardiovascular disease. This review will summarize the available evidence on the short-term and long-term health outcomes of ART singletons, as multiple pregnancies after multiple embryos transfer, are associated with low birth weight and preterm delivery, which can separately increase risk of adverse postnatal outcomes, and impact long-term health. We will also examine the potential factors that may contribute to these health risks, and discuss underlying mechanisms, including epigenetic changes that may occur during the preimplantation period and reprogram development in utero, and adult health, later in life. Lastly, this review will consider the future directions with the view to optimize the long-term health of ART children.

An Update on Oxidative Damage to Spermatozoa and Oocytes

On the one hand, reactive oxygen species (ROS) are mandatory mediators for essential cellular functions including the function of germ cells (oocytes and spermatozoa) and thereby the fertilization process. However, the exposure of these cells to excessive levels of oxidative stress by too high levels of ROS or too low levels of antioxidative protection will render these cells dysfunctional thereby failing the fertilization process and causing couples to be infertile. Numerous causes are responsible for the delicate bodily redox system being out of balance and causing disease and infertility. Many of these causes are modifiable such as lifestyle factors like obesity, poor nutrition, heat stress, smoking, or alcohol abuse. Possible correctable measures include foremost lifestyle changes, but also supplementation with antioxidants to scavenge excessive ROS. However, this should only be done after careful examination of the patient and establishment of the individual bodily antioxidant needs. In addition, other corrective measures include sperm separation for assisted reproductive techniques. However, these techniques have to be carried out very carefully as they, if applied wrongly, bear risks of generating ROS damaging the germ cells and preventing fertilization.

Risk of Monozygotic Twins After Assisted Reproduction: A Population-Based Approach

BACKGROUND

Recent studies have suggested that ovarian stimulation and assisted reproductive techniques (ART) may increase the frequency of monozygotic twins. In this article, we present the analysis of the estimated frequency of twin deliveries following in vitro fertilization (IVF) in Lombardy during the period 2010-2014 for a total of 450,949 pregnancies.

METHOD

This is a population-based study using data from the regional data base of Lombardy, a northern Italian region with a population of about 10 million inhabitants. During the considered period, a total of 461,424 single or multiple births were registered in Lombardy. After exclusion of triplets or more pregnancies, the total number of twin deliveries, in separate strata of like and unlike sex pregnancies twin deliveries, were obtained and the rate of twin deliveries was computed according to spontaneous and non-spontaneous conception and type of ART. Further, estimates of dizygotic or monozygotic twin births were calculated using Weinberg's methods.

RESULTS

The frequency of twins deliveries was 1.24/100 deliveries after natural conception and 20.05 after assisted conception. The estimated rates of monozygotic twins was 0.45 and 0.72/100 (95% CI: 0.58-0.91) deliveries after natural and assisted conception, respectively. This difference was statistically significant (p < .05).

CONCLUSION

the present population based study suggests that the risk of monozygotic twin is about 60% higher among assisted than after natural conception.

Estimating the Risk of Monochorionic Twins in IVF Pregnancies From the Perspective of a Prenatal Diagnosis Unit

The aim of the present work was to estimate the risk of monochorionic twin (MCT) pregnancies in in vitro fertilization (IVF) cycles using data from a prenatal diagnosis unit. This was a retrospective cross-sectional study reporting on the frequency of IVF pregnancies among women attending a prenatal diagnosis service specifically dedicated to the management of monochorionic pregnancies. The observed rate was compared with the local regional rate of IVF births (2.2%). A binomial distribution model was used to calculate the 95% CI of proportions. One hundred and forty-five monochorionic pregnancies were selected. Ten of these were achieved with IVF, corresponding to a rate of 6.9% (95% CI: 3.5–11.8), significantly higher than the background rate in the local population of 2.2%. When considering exclusively monochorionic pregnancies achieving delivery of two viable newborns (n = 132), the number of IVF pregnancies was nine (6.8%, 95% CI: 3.7–12.5). We did not detect major differences in pregnancy outcome between IVF and natural monochorionic pregnancies, with the exception of the proportion of newborns with a neonatal birth < 2,500 g (100% vs. 80%, p = .03). In conclusion, data obtained from the perspective of a prenatal diagnosis unit suggest that women undergoing IVF face a 3- to 4-fold increased risk of monochorionic pregnancies.