Does intracytoplasmic sperm injection pose an increased risk of genitourinary congenital malformations in offspring compared to in vitro fertilization? A systematic review and meta-analysis

A comparison of pregnancy outcomes and congenital malformations in offspring between patients undergoing intracytoplasmic sperm injection and conventional in vitro fertilization: a retrospective cohort study

OBJECTIVE

To explore whether intracytoplasmic sperm injection (ICSI) would increase the malformation risk in fetuses and live births compared with conventional in vitro fertilization (IVF).

DESIGN

Retrospective cohort study.

PATIENT(S)

Data were collected from couples who underwent conventional IVF or ICSI from January 2009 to December 2019 at the Center for Reproductive Medicine of Peking University Third Hospital in the People's Republic of China. A total of 46,167 conventional IVF fresh transfer cycles and 33,247 ICSI fresh transfer cycles were included.

INTERVENTION(S)

Intracytoplasmic sperm injection and conventional IVF.

MAIN OUTCOME MEASURE(S)

The primary outcomes were congenital abnormalities in live births. The secondary outcomes included the pregnancy outcomes, the malformations among the miscarriages, specific types of malformations in live births, birth weight, and sex.

RESULT(S)

The rates of congenital malformations in conventional IVF and ICSI were 5.44‰ and 5.78‰, respectively. There was no statistically significant difference between the two groups, as indicated by the adjusted odds ratio of 1.098 (95% confidence interval 0.787, 1.532). The rates of specific malformations were comparable between ICSI and IVF. Additionally, no discernible disparities were noted in pregnancy outcomes, the malformations among the miscarriages,birth weight between the two groups.

CONCLUSION

Our study suggested the safety of ICSI and provided novel evidence by comparing pregnancy outcomes and congenital malformations in offspring between patients undergoing conventional IVF and ICSI.

Microbiome in Female Reproductive Health: Implications for Fertility and Assisted Reproductive Technologies

The microbiome plays a critical role in the process of conception and the outcomes of pregnancy. Disruptions in microbiome homeostasis in women of reproductive age can lead to various pregnancy complications, which significantly impact maternal and fetal health. Recent studies have associated the microbiome in the female reproductive tract (FRT) with assisted reproductive technology (ART) outcomes, and restoring microbiome balance has been shown to improve fertility in infertile couples. This review provides an overview of the role of the microbiome in female reproductive health, including its implications for pregnancy outcomes and ARTs. Additionally, recent advances in the use of microbial biomarkers as indicators of pregnancy disorders are summarized. A comprehensive understanding of the characteristics of the microbiome before and during pregnancy and its impact on reproductive health will greatly promote maternal and fetal health. Such knowledge can also contribute to the development of ARTs and microbiome-based interventions.

Children born to subfertile couples, how are they doing? Evidence from research

More than 10 million children have been born with assisted reproductive technology (ART) as we begin to enter the third generation of individuals conceived by ART. Here we summarise key messages from an enlarging body of literature regarding their health. Earlier research had pointed towards increases in perinatal, neonatal and neurological risks, such as preterm birth, low birth weight, congenital malformations and cerebral palsy. Many of these risks have continued to persist in most recent work but have shown reduction. Newer research proposes long-term cardiometabolic and endocrine concerns. Fortunately, most reports conclude there is little or no risk of increased childhood malignancy or abnormal neurodevelopment. Moving forward, new research may benefit from changes in comparator groups and a better understanding of infertility per se in ART, and the confounding role it probably plays in many of the known risk associations, to reliably scan the horizon for health threats for individuals born after ART.

Intracytoplasmic sperm injection vs. in-vitro fertilization in couples in whom the male partners had a semen analysis within normal reference ranges: An open debate

During recent decades, the application of intracytoplasmic sperm injection has increased considerably worldwide, especially in couples with non-male factor infertility. However, several studies analyzing the broad use of intracytoplasmic sperm injection, even in cases with a normal semen analysis, have collectively demonstrated no benefits compared to conventional in-vitro fertilization. Currently, there is insufficient evidence to support the intracytoplasmic sperm injection technique vs. in-vitro fertilization in cases of poor ovarian response or a low number of oocytes collected, or in patients with advanced maternal age. Since the intracytoplasmic sperm injection technique is more operator-dependent and invasive, its use should only be recommended in cases of male-factor infertility. There is some evidence showing that intracytoplasmic sperm injection is linked with an increased risk of birth defects. Albeit this evidence is limited, and currently it is not possible to draw a firm conclusion on these concerns, we do believe that these risks should be rigorously investigated. Thus, this review aims to clarify the debate on the application of the intracytoplasmic sperm injection procedure, as compared to standard in-vitro fertilization, in those assisted reproductive technology cycles without a clear male factor infertility. Furthermore, we try to clarify whether intracytoplasmic sperm injection would result in a higher live birth rate than in-vitro fertilization, in couples with non-male factor infertility.

Risk of congenital malformations in live-born singletons conceived after intracytoplasmic sperm injection: a Nordic study from the CoNARTaS group

OBJECTIVE

To investigate whether the risk of major congenital malformations is higher in live-born singletons conceived with intracytoplasmic sperm injection (ICSI) compared with in vitro fertilization (IVF)?

DESIGN

Nordic register-based cohort study.

SETTING

Cross-linked data from Medical Birth Registers and National ART and Patient Registers in Denmark, Norway and Sweden. Data were included from the year the first child conceived using ICSI was born: Sweden, 1992; Denmark, 1994; and Norway, 1996. Data were included until 2014 for Denmark and 2015 for Norway and Sweden.

PATIENT(S)

All live-born singletons conceived using fresh ICSI (n = 32,484); fresh IVF (n = 47,178); without medical assistance (n = 4,804,844); and cryo-ICSI (n = 7,200) during the study period.

INTERVENTION(S)

Different in vitro conception methods, and cryopreservation of embryos.

MAIN OUTCOME MEASURE(S)

Risk of major congenital malformations on the basis of International Classification of Diseases codes. The European Concerted Action on Congenital Anomalies and Twins was used to differentiate between major and minor malformations.

RESULT(S)

Among singletons conceived using fresh ICSI, 6.0% had a major malformation, compared with 5.3% of children conceived using fresh IVF; 4.2% of children conceived without medical assistance; and 4.9% of children conceived using cryo-ICSI; adjusted odds ratio (AOR) 1.07 (95% confidence interval [CI] 1.01-1.14) in ICSI vs. IVF; and AOR 1.28 (95% CI, 1.23-1.35) in ICSI vs. no medical assistance; and AOR 1.11 (95% CI, 0.99-1.26) in ICSI fresh vs. cryo-ICSI. When malformations were grouped by different organ systems, children conceived using ICSI had a higher risk of respiratory and chromosomal malformations compared with children conceived using IVF, but there were very few cases in each group. When categorizing children conceived using ICSI according to treatment indication (male factor infertility only vs. other indications), we found a higher risk of hypospadias when ICSI was performed because of male factor infertility only (AOR 1.85 [95% CI 1.03-332]). The indications for ICSI changed over time, as male factor infertility did not remain the primary indication for ICSI throughout the study period.

CONCLUSION(S)

In this large cohort study, we found the risk of major malformations in live-born singletons to be slightly higher after fresh ICSI compared with fresh IVF. These findings should be considered when choosing the assisted reproductive technology method for couples without male factor infertility.

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

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

The Renaissance of Male Infertility Management in the Golden Age of Andrology

Infertility affects nearly 186 million people worldwide and the male partner is the cause in about half of the cases. Meta-regression data indicate an unexplained decline in sperm concentration and total sperm count over the last four decades, with an increasing prevalence of male infertility. This suggests an urgent need to implement further basic and clinical research in Andrology. Andrology developed as a branch of urology, gynecology, endocrinology, and, dermatology. The first scientific journal devoted to andrological sciences was founded in 1969. Since then, despite great advancements, andrology has encountered several obstacles in its growth. In fact, for cultural reasons, the male partner has often been neglected in the diagnostic and therapeutic workup of the infertile couple. Furthermore, the development of assisted reproductive techniques (ART) has driven a strong impression that this biotechnology can overcome all forms of infertility, with a common belief that having a spermatozoon from a male partner (a sort of sperm donor) is all that is needed to achieve pregnancy. However, clinical practice has shown that the quality of the male gamete is important for a successful ART outcome. Furthermore, the safety of ART has been questioned because of the high prevalence of comorbidities in the offspring of ART conceptions compared to spontaneous conceptions. These issues have paved the way for more research and a greater understanding of the mechanisms of spermatogenesis and male infertility. Consequently, numerous discoveries have been made in the field of andrology, ranging from genetics to several "omics" technologies, oxidative stress and sperm DNA fragmentation, the sixth edition of the WHO manual, artificial intelligence, management of azoospermia, fertility in cancers survivors, artificial testis, 3D printing, gene engineering, stem cells therapy for spermatogenesis, and reconstructive microsurgery and seminal microbiome. Nevertheless, as many cases of male infertility remain idiopathic, further studies are required to improve the clinical management of infertile males. A multidisciplinary strategy involving both clinicians and scientists in basic, translational, and clinical research is the core principle that will allow andrology to overcome its limits and reach further goals. This state-of-the-art article aims to present a historical review of andrology, and, particularly, male infertility, from its "Middle Ages" to its "Renaissance", a golden age of andrology.

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.

Risk of genetic and epigenetic alteration in children conceived following ART: Is it time to return to nature whenever possible?

Assisted reproductive technology may influence epigenetic signature as the procedures coincide with the extensive epigenetic modification occurring from fertilization to embryo implantation. However, it is still unclear to what extent ART alters the embryo epigenome. In vivo fertilization occurs in the fallopian tube, where a specific and natural environment enables the embryo's healthy development. During this dynamic period, major waves of epigenetic reprogramming, crucial for the normal fate of the embryo, take place. Over the past decade, concerns relating to the raised incidence of epigenetic anomalies and imprinting following ART have been raised by several authors. Epigenetic reprogramming is particularly susceptible to environmental conditions during the periconceptional period; therefore, unphysiological conditions, including ovarian stimulation, in vitro fertilization, embryo culture, cryopreservation of gametes and embryos, parental lifestyle, and underlying infertility, have the potential to contribute to epigenetic dysregulation independently or collectively. This review critically appraises the evidence relating to the association between ART and genetic and epigenetic modifications that may be transmitted to the offspring.

Association between perinatal factors and hypospadias in newborns: a retrospective case-control study of 42,244 male infants

Background

Hypospadias is one of the most common male congenital malformations worldwide. It is characterised by the abnormal positioning of the opening of urethra, and may lead to problems with urination and sexual function. Various factors were suggested to contribute to hypospadias pathogen. This study aimed to evaluate the relationship between perinatal factors and neonatal hypospadias based on a large sample of male newborns.

Methods

This retrospective case–control study was conducted at the International Peace Maternal and Child Health Hospital, Shanghai Jiao Tong University School of Medicine. Male infants with hypospadias (N = 97) and without any birth defects (N = 42,147) who were born in January 2015 to December 2019 were enrolled in this study. A statistical analysis of perinatal factors, such as maternal age, primiparity, multiple births, hypertensive disorders of pregnancy (HDP), diabetes mellitus (DM), placenta previa, thyroid diseases, hepatitis B, obesity, meconium-stained amniotic fluid, gestational age, low birth weight (LBW), small for gestational age (SGA) and in vitro fertilization (IVF) was used to assess the risk factors for hypospadias.

Results

The overall incidence of hypospadias in male infants was 0.23% (97/42,244). The univariate analysis of potential risk factors for hypospadias showed that HDP, primiparity, multiple births, hyperthyroidism, preterm delivery, LBW and SGA had a statistical association with hypospadias. After adjusting for potential confounders in a multivariate regression analysis, the odds ratios (OR) and 95% confidence intervals (CI) were calculated for the following risk factors for hypospadias: HDP (OR: 3.965, 95% CI: 2.473–6.359, P <  0.01), multiple births (OR: 2.607, 95% CI: 1.505–4. 514, P <  0.01) and hyperthyroidism (OR:4.792, 95% CI: 1.700–13.506, P <  0.01), which suggested these factors were significant independent risk factors for hypospadias.

Conclusions

Perinatal factors, such as HDP, multiple births and hyperthyroidism may be associated with hypospadias in male infants.

Genetic Factors of Non-Obstructive Azoospermia: Consequences on Patients' and Offspring Health

Non-Obstructive Azoospermia (NOA) affects about 1% of men in the general population and is characterized by clinical heterogeneity implying the involvement of several different acquired and genetic factors. NOA men are at higher risk to be carriers of known genetic anomalies such as karyotype abnormalities and Y-chromosome microdeletions in respect to oligo-normozoospermic men. In recent years, a growing number of novel monogenic causes have been identified through Whole Exome Sequencing (WES). Genetic testing is useful for diagnostic and pre-TESE prognostic purposes as well as for its potential relevance for general health. Several epidemiological observations show a link between azoospermia and higher morbidity and mortality rate, suggesting a common etiology for NOA and some chronic diseases, including cancer. Since on average 50% of NOA patients has a positive TESE outcome, the identification of genetic factors in NOA patients has relevance also to the offspring's health. Although still debated, the observed increased risk of certain neurodevelopmental disorders, as well as impaired cardiometabolic and reproductive health profile in children conceived with ICSI from NOA fathers may indicate the involvement of transmissible genetic factors. This review provides an update on the reproductive and general health consequences of known genetic factors causing NOA, including offspring's health.

Environmental and Genetic Risk Factors of Congenital Anomalies: an Umbrella Review of Systematic Reviews and Meta-Analyses

BACKGROUND

The prevalence of congenital anomalies in newborns in South Korea was 272.9 per 100,000 in 2005, and 314.7 per 100,000 in 2006. In other studies, the prevalence of congenital anomalies in South Korea was equivalent to 286.9 per 10,000 livebirths in 2006, while it was estimated 446.3 per 10,000 births during the period from 2008 to 2014. Several systematic reviews and meta-analyses analyzing the factors contributing to congenital anomalies have been reported, but comprehensive umbrella reviews are lacking.

METHODS

We searched PubMed, Google Scholar, Cochrane, and EMBASE databases up to July 1, 2019, for systematic reviews and meta-analyses that investigated the effects of environmental and genetic factors on any type of congenital anomalies. We categorized 8 subgroups of congenital anomalies classified according to the 10th revision of the International Statistical Classification of Diseases (ICD-10). Two researchers independently searched the literature, retrieved the data, and evaluated the quality of each study.

RESULTS

We reviewed 66 systematic reviews and meta-analyses that investigated the association between non-genetic or genetic risk factors and congenital anomalies. Overall, 269 associations and 128 associations were considered for environmental and genetic risk factors, respectively. Congenital anomalies based on congenital heart diseases, cleft lip and palate, and others were associated with environmental risk factors based on maternal exposure to environmental exposures (air pollution, toxic chemicals), parental smoking, maternal history (infectious diseases during pregnancy, pregestational and gestational diabetes mellitus, and gestational diabetes mellitus), maternal obesity, maternal drug intake, pregnancy through artificial reproductive technologies, and socioeconomic factors. The association of maternal alcohol or coffee consumption with congenital anomalies was not significant, and maternal folic acid supplementation had a preventive effect on congenital heart defects. Genes or genetic loci associated with congenital anomalies included MTHFR, MTRR and MTR, GATA4, NKX2-5, SRD5A2, CFTR, and 1p22 and 20q12 anomalies.

CONCLUSION

This study provides a wide perspective on the distribution of environmental and genetic risk factors of congenital anomalies, thus suggesting future studies and providing health policy implications.

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.

The effect of ICSI in infertility couples with non-male factor: a systematic review and meta-analysis

PURPOSE

We performed a systematic review and meta-analysis of available literature to investigate the efficacy of the intracytoplasmic sperm injection (ICSI) in couples with non-male factor with respect to the clinical outcomes.

METHODS

The literature search was based on EMBASE, PubMed, and the Cochrane Library. All studies published after 1992 until February 2020 and written in English addressing patients in the presence of normal semen parameters subjected to ICSI and in vitro fertilization (IVF) were eligible. Reference lists of retrieved articles were hand-searched for additional studies. The primary outcomes were fertilization rate, clinical pregnancy rate, and implantation rate; the secondary outcomes were good-quality embryo rate, miscarriage rate, and live birth rate.

RESULTS

Four RCTs and twenty-two cohort studies fulfilling the inclusion criteria were included. Collectively, a meta-analysis of the outcomes in RCTs showed that compared to IVF, ICSI has no obvious advantage in fertilization rate (RR = 1.16, 95% CI: 0.83-1.62), clinical pregnancy rate (RR = 1.04, 95% CI: 0.66-1.64), implantation rate (RR = 1.12, 95% CI: 0.67-1.86), and live birth rate (RR = 1.17, 95% CI: 0.43-3.15). Pooled results of cohort studies demonstrated a statistically significant higher fertilization rate (RR = 1.16, 95% CI: 1.03-1.31) and miscarriage rate (RR = 1.04, 95% CI: 1.01-1.06) in the ICSI group; furthermore, higher clinical pregnancy rate (RR = 0.85, 95% CI: 0.77-0.94), implantation rate (RR = 0.78, 95% CI: 0.65-0.95), and live birth rate (RR = 0.86, 95% CI: 0.79-0.94) was founded in the IVF group; no statistically significant difference was observed in good-quality embryo rate (RR = 0.98, 95% CI: 0.93-1.04).

CONCLUSION

ICSI has no obvious advantage in patients with normal semen parameters. Enough information is still not available to prove the efficacy of ICSI in couples with non-male factor infertility comparing to IVF.

Assessment of operant learning and memory in mice born through ICSI

STUDY QUESTION

Are there differences in operant learning and memory between mice born through ICSI and naturally conceived control (CTL) mice?

SUMMARY ANSWER

ICSI females exhibited deficits in the acquisition reward learning relative to CTL females, and ICSI males exhibited deficiencies in discrimination learning and memory relative to CTL males.

WHAT IS KNOWN ALREADY

Some human outcome studies have suggested that ICSI might be associated with an increased risk of certain cognitive disorders, but only one of two behavioral studies with ICSI mouse models have reported differences between ICSI and CTL females. No studies to date have investigated associative learning in ICSI mice.

STUDY DESIGN, SIZE, DURATION

Groups of 36 ICSI mice (18 male, 18 female) and 37 CTL mice (19 male, 18 female) aged 3-6 months were compared in a series of operant learning procedures that assessed acquisition of a new behavior, discrimination learning and memory. In total, 16 ICSI mice (9 male, 7 female) and 17 CTL mice (10 male, 7 female) received follow-up discrimination learning and memory assessments at 12 months of age (6 months after the end of initial training) to evaluate retention and reacquisition of learned performances.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Mice received daily operant learning sessions in experimental chambers in which all stimulus events and the recording of responses were automated. Food rewards were delivered for responding under different conditions of reinforcement, which varied by procedure. Subjects received a successive series of sessions of nose poke acquisition training, discrimination training and the delayed-non-matching-to-position memory procedure. Mixed repeated measures ANOVAs in which the between-subjects factor was group (ICSI vs CTL) and the within-subjects factor was repeated exposures to learning procedures (i.e. sessions) were used to analyze data.

MAIN RESULTS AND THE ROLE OF CHANCE

In comparisons between all mice (i.e. males and females combined), CTL mice exhibited superior performance relative to ICSI in response acquisition (P = 0.03), discrimination (P = 0.001) and memory (P = 0.007). Sex-specific comparisons between the groups yielded evidence of sexual dimorphism. ICSI females exhibited a deficit in acquisition learning relative to CTL females (P < 0.001), but there was not a significant difference between CTL and ICSI males. In the discrimination and memory tasks, ICSI males exhibited deficits relative to CTL males (P = 0.002 and P = 0.02, respectively) but the differences between females in these tasks were not significant. There was no difference in discrimination or memory retention/re-acquisition assessments conducted with mice at 12 months of age. ICSI males and females weighed significantly more than CTL counterparts at all points during the experiment.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The study was not blinded. All learning assessments utilized food reward; other assessments of operant, Pavlovian and nonassociative learning are needed to fully characterize learning in ICSI mice and speculate regarding the implications for cognitive function in humans conceived via ICSI.

WIDER IMPLICATIONS OF THE FINDINGS

Studying learning and memory processes in mouse models have the potential to shed light on ICSI outcomes at the level of cognitive function. Future research should use multiple learning paradigms, assess both males and females, and investigate the effects of variables related to the ICSI procedure. Studying cognitive function in ICSI is an interdisciplinary endeavor and requires co-ordination between researchers at the genetic and psychological levels of analysis.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported, in part, by grants from the NIH (P30GM110767, HD071736 and HD085506 to W.Y.), the Templeton Foundation (61174 to W.Y.) and a New Scholarly Endeavor Grant from the University of Nevada, Reno Office of Research and Innovation (to M.L., Y.W., H.Z., L.H. and W.Y.). The authors declare no competing interests.

Perinatal outcome in children born after assisted reproductive technologies

Over the past 40 years access and effectiveness of assisted reproductive technologies (ART) have increased, and to date more than 8 million children have been conceived after ART globally. Most pregnancies resulting from ART are uncomplicated and result in the birth of healthy children. Yet, it is well known that pregnancies following ART are more likely to be affected by obstetric complications such as hypertensive disorders in pregnancy, preterm birth, and low birth weight compared with spontaneously conceived pregnancies. ART children are also at increased risk of birth defects. The majority of the problems arise as a result of multiple pregnancies and can be reduced by transferring a single embryo, thereby avoiding multiple pregnancies. New ART technologies are constantly introduced, and monitoring of the health of ART children is crucial.

In Vitro Fertilization Technology and Child Health

BACKGROUND

Just under 3% of children in Germany, and approximately 6% of children in some other countries, such as Denmark, are now being conceived with the aid of in vitro fertilization (IVF) technology. Alongside the increased risk of organ malformation, there is now evidence for functional abnormalities due to epigenetic modifications.

METHODS

This review is based on pertinent publications retrieved by a literature search on currently known associations of IVF therapy with malformations and functional abnormalities. The potential implications for the treatment of infertility are discussed.

RESULTS

The risk of congenital malformations is approximately one-third higher in children conceived with the aid of IVF technology than in other children; specifically, there is an odds ratio (OR) of 1.29 (95% confidence interval, [1.03; 1.60]) for cardiac malformations, and there is a relative risk (RR) of 1.35 ([1.12; 1.64]) for musculo- skeletal malformations and 1.58 ([1.28; 1.94]) for genitourinary malformations. The risks of preterm birth and low birth weight are, respectively, 1.7 and 1.5 times higher in IVF singleton pregnancies than in non-IVF pregnancies. Cardiovascular changes are the main type of functional disturbance. Some of the risks associated with IVF have decreased in recent years. An association has been revealed between cardiovascular abnormalities and epigenetic modifications; the causes are thought to include not only maternal and paternal factors, but also the IVF techniques that are used. A modification of IVF therapies might lower the risks, but might also lower the success rate.

CONCLUSION

For the well-being of the children to be conceived, IVF therapy should hat cannot be treated by any other means, as the precise causes of the risks of IVF to child health are unclear.

Altered TH1, TH2, TH17 balance in assisted reproductive technology conceived mice

AIM AND PURPOSE

The higher prevalence rate of different diseases may accentuate the possible alteration of the immune system in individuals conceived through the assisted reproductive technologies (ART). The present study was conducted to evaluate the TH1, TH2, TH17 balance in intracytoplasmic sperm injection (ICSI) and in vitro fertilization (IVF) - conceived mice in comparison to naturally conceived offspring.

METHODS

Mice (6-8 weeks) were divided into three groups (IVF- conceived, ICSI- conceived and naturally conceived). They were subjected to subcutaneous immunization witMycobacterium bovis Bacille Calmette-Guérin (BCG). The blood samples were taken and the sera were separated. Then the spleens were surgically removed at the time the mice were sacrificed. Serum levels of IFN-γ, IL-17A and IL-4 were detected by ELISA. Then the proportion of TCD4 cells possessing the T-bet+, GATA3+, and ROR-γt + were measured using FACS caliber flow cytometer.

RESULTS

In comparison with naturally conceived mice, intracellular expression of T-bet and serum levels of IFN-γ were significantly decreased in ART- conceived mice. Moreover, ART- conceived offspring showed marked increase in IL-4 and IL-17A.

CONCLUSION

It is concluded that compared to naturally conceived male mice, ART- conceived counterparts exhibit less efficient immune responses against BCG through further promotion of humoral and inflammatory related immune response characteristics.

Alteration in the expression of the renin-angiotensin system in the myocardium of mice conceived by in vitro fertilization

Epidemiological studies have revealed that offspring conceived by in vitro fertilization (IVF) have an elevated risk of cardiovascular malformations at birth, and are more predisposed to cardiovascular diseases. The renin-angiotensin system (RAS) plays an essential role in both the pathogenesis of congenital heart disease in fetuses and cardiovascular dysfunction in adults. This study aimed to assess the relative expression levels of genes in the RAS pathway in mice conceived using IVF, compared to natural mating with superovulation. Results demonstrated that expression of the angiotensin II receptor type 1 (AGTR1), connective tissue growth factor (CTGF), and collagen 3 (COL3), in the myocardial tissue of IVF-conceived mice, was elevated at 3 weeks, 10 weeks, and 1.5 years of age, when compared to their non-IVF counterparts. These data were supported by microRNA microarray analysis of the myocardial tissue of aged IVF-conceived mice, where miR-100, miR-297, and miR-758, which interact with COL3, AGTR1, and COL1 respectively, were upregulated when compared to naturally mated mice of the same age. Interestingly, bisulfite sequencing data indicated that IVF-conceived mice exhibited decreased methylation of CpG sites in Col1. In support of our in vivo investigations, miR-297 overexpression was shown to upregulate AGTR1 and CTGF, and increased cell proliferation in cultured H9c2 cardiomyocytes. These findings indicate that the altered expression of RAS in myocardial tissue might contribute to cardiovascular malformation and/or dysfunction in IVF-conceived offspring. Furthermore, these cardiovascular abnormalities might be the result of altered DNA methylation and abnormal regulation of microRNAs.

Intracytoplasmic sperm injection for male infertility and consequences for offspring

Intracytoplasmic sperm injection (ICSI) has become the most commonly used method of fertilization in assisted reproductive technology. The primary reasons for its popularity stem from its effectiveness, the standardization of the procedure, which means that it can easily be incorporated into the routine practice of fertility centres worldwide, and the fact that it can be used to treat virtually all forms of infertility. ICSI is the clear method of choice for overcoming untreatable severe male factor infertility, but its (over)use in other male and non-male factor infertility scenarios is not evidence-based. Despite all efforts to increase ICSI efficacy and safety through the application of advanced sperm retrieval and cryopreservation techniques, as well as methods for selecting sperm with better chromatin integrity, the overall pregnancy rates from infertile men remain suboptimal. Treating the underlying male infertility factor before ICSI seems to be a promising way to improve ICSI outcomes, but data remain limited. Information regarding the health of ICSI offspring has accumulated over the past 25 years, and there are reasons for concern as risks of congenital malformations, epigenetic disorders, chromosomal abnormalities, subfertility, cancer, delayed psychological and neurological development, and impaired cardiometabolic profile have been observed to be greater in infants born as a result of ICSI than in naturally conceived children. However, as subfertility probably influences the risk estimates, it remains to be determined to what extent the observed adverse outcomes are related to parental factors or associated with ICSI.

Male subfertility and the risk of major birth defects in children born after in vitro fertilization and intracytoplasmic sperm injection: a retrospective cohort study

Background

Children born after intracytoplasmic sperm injection (ICSI) are at increased risk of specific major birth defects compared with children born after in vitro fertilization (IVF). However, whether this risk is due to the treatment itself (i.e., IVF or ICSI) or underlying male subfertility is unknown. This study investigated the associations between male subfertility and the risk of major birth defects in children born after IVF and ICSI.

Methods

We conducted a retrospective cohort study using data from the Japanese assisted reproductive technology registry between 2007 and 2014. Fresh embryo transfer cycles registered from 2007 to 2014 that resulted in singleton live births, still births, or selective terminations were included (n = 59,971). Major birth defects were defined by the US Centers for Disease Control and Prevention guidelines, excluding chromosomal abnormalities. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using generalized estimating equations adjusting for potential confounders.

Results

Major birth defects were reported in 626/59,971 (1.04%) cases. Among IVF cycles, male subfertility was associated with significantly greater risks of hypospadias (3/3163 [0.09%] vs 4/28,671 [0.01%], adjusted OR = 6.85, 95% CI 2.05–22.9, P = 0.002) and atrial septal defects (4/3163 [0.13%] vs 9/28,671 [0.03%], adjusted OR = 3.98, 95% CI 1.12–14.1, P = 0.03) compared with fertile men. Subgroup analysis using sperm parameters showed that oligozoospermia (i.e., sperm concentrations < 15 million/mL) was significantly associated with a greater risk of ventricular septal defects compared with normal sperm concentrations in IVF pregnancies (5/868 [0.58%] vs 60/28,090 [0.21%], adjusted OR = 2.68, 95% CI 1.15–6.27, P = 0.02), and severe oligozoospermia (i.e., sperm concentrations < 5 million/mL) was significantly associated with an increased risk of hypospadias compared with normal sperm concentrations in ICSI pregnancies (5/3136 [0.16%] vs 5/16,865 [0.03%], adjusted OR = 3.88, 95% CI 1.14–13.2, P = 0.03).

Conclusions

The results of this exploratory study suggest that underlying male subfertility may play a role in the risk of major birth defects related to ICSI and IVF. Further research, including systematic reviews adjusting for confounders, is required to confirm the associations between male subfertility and major cardiac and urogenital birth defects.

Electronic supplementary material

The online version of this article (10.1186/s12884-019-2322-7) contains supplementary material, which is available to authorized users.

Endocrine and reproductive profile of boys and young adults conceived after ICSI

PURPOSE OF REVIEW

The impact of intracytoplasmic sperm injection (ICSI), on the reproductive health of the offspring is largely unknown. Here we provide a comprehensive overview of the endocrine and reproductive profile in boys and young male adults born after ICSI using ejaculated spermatozoa alleviating male factor infertility in their parents.

RECENT FINDINGS

Levels of testosterone, anti-Müllerian hormone and inhibin B were found comparable in prepubertal and pubertal boys conceived by ICSI when compared with levels in boys conceived spontaneously. Also, at young adulthood, mean levels of reproductive hormones did not differ from control peers. However, semen analysis showed significantly lower sperm concentration, total sperm count and total motile sperm count when compared with controls. Furthermore, the risk of having sperm concentration and sperm count below the reference values was increased in ICSI offspring while sperm parameters did not correlate in paired father-son semen analysis.

SUMMARY

Although endocrine gonadal function was normal at puberty, exocrine function at young adulthood was not. We observed decreased semen quality and quantity in young adults conceived by ICSI performed to circumvent male factor infertility. The possibility of transgenerational transmission of impaired spermatogenesis after ICSI needs further investigation.

A retrospective population-based cohort study to evaluate the impact of an older sibling with undescended testis and hypospadias on the known maternal and fetal risk factors for undescended testis and hypospadias in Ontario, Canada, 1997-2007

INTRODUCTION

There are several reported risk factors for undescended testis (UDT) and hypospadias (HYP). Also, a family history of UDT or HYP has not been accounted for in prior studies, and doing so may influence these independent risk estimates.

STUDY DESIGN

A population-based retrospective cohort study was conducted using linked administrative databases in Ontario, Canada, to identify all live male newborns born between 1997 and 2007, and it was determined whether they underwent an orchidopexy or HYP repair within 5 years of birth. Baseline maternal and fetal risk factors were obtained using appropriate ICD codes. A statistical analysis using a generalized estimating equation with a logit link was performed, adjusting for clustering in mothers with a previous child born in the 5 years before the proband with UDT or HYP, to evaluate the adjusted risk factors of UDT and HYP.

RESULTS

A total of 709,968 male infants were followed up from birth for 5 years, of which 5830 underwent an orchidopexy and 2722 had an HYP repair. On multivariable analysis, factors associated with a higher risk of UDT included prematurity, small for gestational age (SGA), associated HYP, gestational hypertension, use of assisted fertility techniques, increased maternal age, Cesarean section, previous sibling with UDT, and disorders of sexual differentiation (DSDs). After adjusting for clustering in mothers with a previous baby with UDT, DSD, associated HYP (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.0-4.1), and a previous sibling with UDT (OR, 3.6; 95% CI, 2.5-5.2) remained significant risk factors. The risk factors on multivariable analysis predicting the risk of HYP included SGA, prematurity, higher income families, and associated anomalies such as UDT. After adjusting for clustering in mothers with a previous sibling with HYP, SGA (OR, 1.8; 95% CI, 1.0-3.1), higher income families (OR, 1.5-1.6), associated UDT (OR, 7.1; 95% CI, 4.9-10.0), and a previous sibling with HYP (OR, 12.8; 95% CI, 9.1-18.1) remained significant risk factors.

DISCUSSION

Studies estimating risk factors for UDT and HYP have used variable methodologies to identify index cases and perform statistical analysis. This study suggests that having an older sibling with UDT or HYP is a significant independent risk factor. Performing an analysis adjusting for clustering in mothers with a previous child with UDT or HYP leads to loss of statistical significance for other described risk factors.

CONCLUSION

Underlying genetic or similar environmental exposures may be a key risk factor for UDT and HYP, which confounds known maternal and fetal risk factors for these anomalies.

Genetic counseling prior to Assisted Reproductive Technology procedures in the era of cytogenomics

The possibility of sequencing hundreds of genes simultaneously and performing molecular karyotyping thanks to the introduction of novel genetic tools has expanded the use of preconception screening for blastocyst recessive mutations and aneuploidies before embryo transfer, with the ultimate purpose of increasing the proportion of normal healthy newborns. Since medically-assisted reproduction procedures are increasingly required to be eugenic, and the aforementioned genetic tests cover only half of the potential genetic diseases occurring at birth, it seems reasonable to incorporate genetic counseling in the practice of assisted reproduction to avoid prosecution for malpractice.

Are children born from singleton pregnancies conceived by ICSI at increased risk for congenital malformations when compared to children conceived naturally? A systematic review and meta-analysis

Since 1992, the development of intra-cytoplasmic sperm injection (ICSI) has allowed infertile couples and couples affected by severe male factor infertility in particular, many of which with a history of failed traditional IVF, to become parents. This has generated considerable controversy over the safety of the procedure for the offspring. This systematic review seeks to determine whether evidence indicates that the use of ICSI increases the risk of congenital malformation in children born from singleton pregnancies versus naturally conceived children. Twenty-one of the 104 publications listed in the literature search were included in the analysis. Observational studies reported mostly an increased risk for congenital malformation; the risk of congenital malformations is 7.1% in ICSI and 4.0% in the general population (OR 1.99 (95% CI [1.87 - 2.11]). However, attributing higher risk solely to ICSI might seem far-fetched, as in vitro and simulation procedures, patient diseases, and ICSI indication may also be associated with higher risk of malformation.

Risk factors for cryptorchidism

Undescended testis - known as cryptorchidism - is one of the most common congenital abnormalities observed in boys, and is one of the few known risk factors for testicular cancer. The key factors that contribute to the occurrence of cryptorchidism remain elusive. Testicular descent is thought to occur during two hormonally-controlled phases in fetal development - between 8-15 weeks (the first phase of decent) and 25-35 weeks gestation (the second phase of descent); the failure of a testis to descend permanently is probably caused by disruptions to one or both of these phases, but the causes and mechanisms of such disruptions are still unclear. A broad range of putative risk factors have been evaluated in relation to the development of cryptorchidism but their plausibility is still in question. Consistent evidence of an association with cryptorchidism exists for only a few factors, and in those cases in which evidence seems unequivocal the factor is likely to be a surrogate for the true causal exposure. The relative importance of each risk factor could vary considerably between mother-son pairs depending on an array of genetic, maternal, placental and fetal factors - all of which could vary between regions. Thus, the role of causative factors in aetiology of cryptorchidism requires further research.

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.

Assisted Reproductive Technology and Birth Defects Among Liveborn Infants in Florida, Massachusetts, and Michigan, 2000-2010

IMPORTANCE

Use of assisted reproductive technology (ART) has been associated with increased risks for birth defects. Variations in birth defect risks according to type of ART procedure have been noted, but findings are inconsistent.

OBJECTIVES

To examine the prevalence of birth defects among liveborn infants conceived with and without ART and to evaluate risks associated with certain ART procedures among ART-conceived infants.

DESIGN, SETTING, AND PARTICIPANTS

Used linked ART surveillance, birth certificates, and birth defects registry data for 3 states (Florida, Massachusetts, and Michigan). Methods for ascertaining birth defect cases varied by state. Resident live births during 2000 to 2010 were included, and the analysis was conducted between Feburary 2015 and August 2015.

EXPOSURES

Use of ART among all live births and use of certain ART procedures among ART births.

MAIN OUTCOME AND MEASURES

Prevalence of selected chromosomal and nonchromosomal birth defects that are usually diagnosed at or immediately after birth.

RESULTS

Of the 4 618 076 liveborn infants between 2000 and 2010, 64 861 (1.4%) were conceived using ART. Overall, the prevalence of 1 or more of the selected nonchromosomal defects was 58.59 per 10 000 for ART infants (n = 389) vs 47.50 per 10 000 for non-ART infants (n = 22 036). The association remained significant after adjusting for maternal characteristics and year of birth (adjusted risk ratio [aRR], 1.28; 95% CI, 1.15-1.42). Similar differences were observed for singleton ART births vs their non-ART counterparts (63.69 per 10 000 [n = 218] vs 47.17 per 10 000 [n = 21 251]; aRR, 1.38; 95% CI, 1.21-1.59). Among multiple births, the prevalence of rectal and large intestinal atresia/stenosis was higher for ART births compared with non-ART births (aRR, 2.39; 95% CI, 1.38-4.12). Among ART births conceived after fresh embryo transfer, infants born to mothers with ovulation disorders had a higher prevalence of nonchromosomal birth defects (aRR, 1.53; 95% CI, 1.13-2.06) than those born to mothers without the diagnosis, and use of assisted hatching was associated with birth defects among singleton births (aRR, 1.55; 95% CI, 1.10-2.19). Multiplicity-adjusted P values for these associations were greater than .05.

CONCLUSIONS AND RELEVANCE

Infants conceived after ART had a higher prevalence of certain birth defects. Assisted hatching and diagnosis of ovulation disorder were marginally associated with increased risks for nonchromosomal birth defects; however, these associations may be caused by other underlying factors.