Risk of major congenital anomalies after assisted hatching: analysis of three-year data from the national assisted reproduction registry in Japan

A multicentre double-blinded randomized controlled trial on the efficacy of laser-assisted hatching in patients with repeated implantation failure undergoing IVF or ICSI

STUDY QUESTION

Does assisted hatching increase the cumulative live birth rate in subfertile couples with repeated implantation failure?

SUMMARY ANSWER

This study showed no evidence of effect for assisted hatching as an add-on in subfertile couples with repeated implantation failure.

WHAT IS KNOWN ALREADY

The efficacy of assisted hatching, with regard to the live birth rate has not been convincingly demonstrated in randomized trials nor meta-analyses. It is suggested though that especially poor prognosis women, e.g. women with repeated implantation failure, might benefit most from assisted hatching.

STUDY DESIGN, SIZE, DURATION

The study was designed as a double-blinded, multicentre randomized controlled superiority trial. In order to demonstrate a statistically significant absolute increase in live birth rate of 10% after assisted hatching, 294 participants needed to be included per treatment arm, being a total of 588 subfertile couples. Participants were included and randomized from November 2012 until November 2017, 297 were allocated to the assisted hatching arm of the study and 295 to the control arm. Block randomization in blocks of 20 participants was applied and randomization was concealed from participants, treating physicians, and laboratory staff involved in the embryo transfer procedure. Ovarian hyperstimulation, oocyte retrieval, laboratory procedures, embryo selection for transfer and cryopreservation, the transfer itself, and luteal support were performed according to local protocols and were identical in both the intervention and control arm of the study with the exception of the assisted hatching procedure which was only performed in the intervention group. The laboratory staff performing the assisted hatching procedure was not involved in the embryo transfer itself.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were eligible for inclusion in the study after having had either at least two consecutive fresh IVF or ICSI embryo transfers, including the transfer of frozen and thawed embryos originating from those fresh cycles, and which did not result in a pregnancy or as having had at least one fresh IVF or ICSI transfer and at least two frozen embryo transfers with embryos originating from that fresh cycle which did not result in a pregnancy. The study was performed at the laboratory sites of three tertiary referral hospitals and two university medical centres in the Netherlands.

MAIN RESULTS AND THE ROLE OF CHANCE

The cumulative live birth rate per started cycle, including the transfer of fresh and subsequent frozen/thawed embryos if applicable, resulted in 77 live births in the assisted hatching group (n = 297, 25.9%) and 68 live births in the control group (n = 295, 23.1%). This proved to be statistically not significantly different (relative risk: 1.125, 95% CI: 0.847 to 1.494, P = 0.416).

LIMITATIONS, REASONS FOR CAUTION

There was a small cohort of subfertile couples that after not achieving an ongoing pregnancy, still had cryopreserved embryos in storage at the endpoint of the trial, i.e. 1 year after the last randomization. It cannot be excluded that the future transfer of these frozen/thawed embryos increases the cumulative live birth rate in either or both study arms. Next, at the start of this study, there was no international consensus on the definition of repeated implantation failure. Therefore, it cannot be excluded that assisted hatching might be effective in higher order repeated implantation failures.

WIDER IMPLICATIONS OF THE FINDINGS

This study demonstrated no evidence of a statistically significant effect for assisted hatching by increasing live birth rates in subfertile couples with repeated implantation failure, i.e. the couples which, based on meta-analyses, are suggested to benefit most from assisted hatching. It is therefore suggested that assisted hatching should only be offered if information on the absence of evidence of effect is provided, at no extra costs and preferably only in the setting of a clinical trial taking cost-effectiveness into account.

STUDY FUNDING/COMPETING INTEREST(S)

None.

TRIAL REGISTRATION NUMBER

Netherlands Trial Register (NTR 3387, NL 3235, https://www.clinicaltrialregister.nl/nl/trial/26138).

TRIAL REGISTRATION DATE

6 April 2012.

DATE OF FIRST PATIENT’S ENROLMENT

28 November 2012.

Placental histology following assisted hatching in fresh transfer cycles

PURPOSE

To assess placental histological findings following assisted hatching in fresh transfer in vitro fertilization cycles.

METHODS

Evaluation of a historic cohort of live singleton deliveries after fresh embryo transfer (ET) at a single university medical center between 2009 and 2017. We compared perinatal outcomes and placental histology in cases where assisted hatching was performed prior to ET (AH group) and cases with no AH (no AH group).

RESULTS

Overall, 166 deliveries following AH were compared to 494 deliveries with no AH. Patients' demographics were similar between the groups. Median antral follicle count was significantly lower in the AH group, median 11 (range 1-50) vs. 16 (range 1-80), p < 0.001, and the primary indication for infertility treatment significantly more often diminished ovarian reserve (p < 0.001). Cycle characteristics in the AH group included a higher gonadotropin dose employed, and a lower rate of single and blastocyte transfer. Pregnancies following AH were associated with less low-lying placentas, 0.6% vs. 6.2%, p = 0.001, and comparable for other perinatal outcomes. After adjusting for confounders, the rate of bilobated placentas was higher following AH, aOR 7.10, 95% CI 1.50-33.51. The rate of perivillous depositions was higher with AH, aOR, 95% CI 3.18, 1.46-6.93, and the rate of chorangiosis lower in this group, aOR, 95% CI 0.32, 0.11-0.93. The overall rate of vascular lesions was similar between the groups.

CONCLUSION

Pregnancies following AH are notable for a lower rate of placenta previa, yet a higher rate of bilobated placentas and perivillous depositions and less chorangiosis, warranting further investigation.

The efficacy of add-ons: selected IVF "add-on" procedures and future directions

Since the advent of ART, technology has continuously evolved to improve embryology and pregnancy outcomes. However, not all technologies that are integrated into practice have convincing evidence of clinical effectiveness, and they often increase the financial burden of fertility care. We discuss here a selection of commonly utilized IVF "add-ons" and discuss the existing evidence for their utility. The procedures included in this review are time-lapse imaging of embryos, assisted hatching, EmbryoGlue, sperm DNA testing, egg activation with calcium ionophore, endometrial receptivity array, and physiological intracytoplasmic sperm injection (PICSI). While there is rather limited supporting evidence for nearly all IVF add-ons that we reviewed, there is strong demand from patients, physicians, and the biotechnology industry to continue further research and development in this arena. We propose that all add-on procedures should provide true efficacy for the patient, and reproductive endocrinologists should inform patients of the costs and benefits of utilizing various technologies before they undergo treatment. In the future, add-ons that show clear evidence of efficacy and justifiable cost should be incorporated into routine practice, while others that do not meet these criteria should be phased out entirely.

Obstetric and perinatal outcomes of singleton pregnancies after blastocyst-stage embryo transfer compared with those after cleavage-stage embryo transfer: a systematic review and cumulative meta-analysis

BACKGROUND

Extended embryo culture to blastocyst stage is widely used in IVF and is the default strategy in most clinics. The last decade has witnessed a growing interest in obstetric-perinatal outcomes following blastocyst transfer. Recent studies have challenged the conclusions of systematic reviews that associate risks of preterm birth (PTB) and large for gestational age (LGA) babies with blastocyst transfer. A higher proportion of blastocysts is transferred as frozen-thawed embryos, which may also have added implications.

OBJECTIVE AND RATIONALE

The aim of this study was to conduct an updated systematic review of the obstetric-perinatal outcomes in singleton pregnancies following blastocyst-stage transfer compared to cleavage-stage transfer in IVF/ICSI cycles. Where deemed appropriate, data were combined in cumulative meta-analyses.

SEARCH METHODS

Data sources from Medline, EMBASE, CINAHL, Web of Science, the Cochrane Central Register of Clinical Trials and the International Clinical Trials Registry Platform (ICTRP) (1980-2020) were searched using combinations of relevant keywords. Searches had no language restrictions and were limited to human studies. Observational studies and randomized controlled trials comparing obstetric-perinatal outcomes between singleton pregnancies after blastocyst-stage transfer and those after cleavage-stage transfer in IVF/ICSI cycles were sought. Two independent reviewers extracted data in 2 × 2 tables and assessed the methodological quality of the relevant studies using the Critical Appraisal Skills Programme scoring. Cumulative meta-analyses were carried out with independent analysis of pregnancies after fresh and frozen embryo transfers, using the Comprehensive Meta-Analysis software. If provided by included studies, adjusted effect sizes were combined in a sensitivity analysis.

OUTCOMES

A total of 35 studies were included (n = 520 769 singleton pregnancies). Outcome data suggest singleton pregnancies following fresh blastocyst transfer were associated with higher risk of LGA (risk ratio (RR) 1.14; 95% CI 1.05-1.24) and very PTB (RR 1.17; 95% CI 1.08-1.26) compared to fresh cleavage-stage transfer. Singleton pregnancies following frozen blastocyst transfer were associated with higher risks of LGA (RR 1.17; 95% CI 1.08-1.27), PTB (RR 1.13; 95% CI 1.03-1.24) and caesarean section (RR 1.08; 95% CI 1.03-1.13) but lower risks of small for gestational age (RR 0.84, 95% CI 0.74-0.95) and perinatal mortality (RR 0.70; 95% CI 0.58-0.86). Increased risks of LGA and PTB after frozen blastocyst transfer persisted in the sensitivity analysis, which also showed a significantly increased risk of PTB after fresh blastocyst transfer. Cumulative meta-analyses revealed consistency in prevalence and magnitude of risks for a number of years. Data on other perinatal outcomes are still evolving.

WIDER IMPLICATIONS

While the available evidence is predominantly reassuring in the context of blastocyst-stage embryo transfer, observational data suggest that blastocyst transfer is associated with a higher risk of LGA. This holds true irrespective of fresh or frozen transfer. Meta-analysis of adjusted data showed an increased risk of PTB with fresh and frozen blastocyst transfer. However, the quality of available evidence ranges from low to very low. Although blastocyst-stage embryo transfer remains the default position in most centres, based on individual risk profile we may need to consider cleavage-stage embryo transfer in some to mitigate the risk of LGA/PTB.

Laser-assisted hatching on clinical and neonatal outcomes in patients undergoing single vitrified Blastocyst transfer: A propensity score-matched study

PURPOSE

This study determined the effect of laser-assisted hatching on the clinical and neonatal outcomes of single vitrified blastocyst transfer.

METHODS

From June 2014 to March 2018, 289 matched pairs after propensity score matching were analyzed. During the blastocyst warming procedure, a small section of the zona pellucida area in the empty perivitelline space was sliced off using multiple laser beams. The clinical and neonatal outcomes of the laser-treated group and non-treatment control were analyzed.

RESULTS

In the laser-assisted hatching group, significantly higher rates of clinical pregnancy (40.8% vs 29.4%, P < .01) and live delivery (34.3% vs 22.5%, P < .01) were observed compared to the control group. Other variables such as the average gestational weeks, the sex of the baby, birthweight, or congenital malformations were found to have no significant differences in neonatal outcomes. Moreover, all babies were singleton live births.

CONCLUSIONS

Single vitrified blastocyst transfer treated with laser-assisted hatching increases the live birth rate and has no adverse effects on neonatal outcomes.

Assisted reproductive technologies and the risk of congenital urogenital tract malformations: A systematic review and meta-analysis

A systematic review was conducted to evaluate the relationship between ART and the risk of urogenital tract malformations, especially hypospadias and cryptorchidism. Thirty-three papers were selected. Meta-analysis showed that ART was correlated with an increased risk of urogenital tract malformation in offspring (odds ratio (OR) = 1.61, 95% confidence interval (CI): 1.41-1.85), hypospadias (OR = 1.87, 95% CI: 1.47-2.40) and cryptorchidism (OR = 1.83, 95% CI: 1.54-2.18). Among offspring conceived by ART, multiple pregnancies appeared to result in a higher risk of urogenital tract malformation than singleton pregnancies (OR = 1.42, 95% CI: 0.99-2.04; P = 0.058). No significant difference in the risk of urogenital tract malformation was found between in vitro fertilization and intracytoplasmic sperm injection technologies. A sensitivity analysis showed that the above conclusions were relatively consistent. Conclusion: ART is correlated with an increased risk of urogenital tract malformations in offspring, especially hypospadias and cryptorchidism. Among ART offspring, multiple pregnancies may lead to a higher risk of urogenital tract malformations than singleton pregnancies, but more studies are needed for confirmation.

Obstetric, neonatal and child development outcomes following assisted hatching treatment: a retrospective cohort study

Assisted hatching (AH) involves artificial disruption of the zona pellucida prior to embryo transfer. The purpose of this study is to examine the safety of AH technique and its effect on obstetrical, perinatal and neonatal outcomes and risk of developmental delay. This is a retrospective cohort of ART cycles using laser AH technique. The study group consisted of 120 cases of AH cycles resulting in singleton pregnancies and live births compared with 113 control cases. A current phone questionnaire was conducted to assess child development in the first year of life. AH was not associated with increased risk for all obstetrical and perinatal outcomes examined including PPROM, gestational diabetes, hypertensive diseases of pregnancy, delivery by cesarean section, gestational age at delivery, low birth weight (LBW), preterm birth and neonatal Apgar score (p>.05). No significant differences were observed between AH and control group in rates and risk of congenital malformations (5.8 vs. 4.4%, respectively, OR 1.33, 95% CI 0.41-4.34) and developmental delay (19.2 vs. 12.8%, respectively, OR 1.62, 95% CI 0.74-3.52). AH did not increase the risk of obstetrical and neonatal complications in singleton pregnancies, including congenital malformations and child developmental delay. AH may therefore be considered a safe method of ART.

The risk of birth defects with conception by ART

STUDY QUESTION

What is the association between ART conception and treatment parameters and the risk of birth defects?

SUMMARY ANSWER

Compared to naturally conceived singleton infants, the risk of a major nonchromosomal defect among ART singletons conceived with autologous oocytes and fresh embryos without use of ICSI was increased by 18%, with increases of 42% and 30% for use of ICSI with and without male factor diagnosis, respectively.

WHAT IS KNOWN ALREADY

Prior studies have indicated that infertility and ART are associated with an increased risk of birth defects but have been limited by small sample size and inadequate statistical power, failure to differentiate results by plurality, differences in birth defect definitions and methods of ascertainment, lack of information on ART treatment parameters or study periods spanning decades resulting in a substantial historical bias as ART techniques have improved.

STUDY DESIGN, SIZE, DURATION

This was a population-based cohort study linking ART cycles reported to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) from 1 January 2004 to 31 December 2015 that resulted in live births from 1 September 2004 to 31 December 2016 in Massachusetts and North Carolina and from 1 September 2004 to 31 December 2015 for Texas and New York: these were large and ethnically diverse States, with birth defect registries utilizing the same case definitions and data collected, and with high numbers of ART births annually. A 10:1 sample of non-ART births were chosen within the same time period as the ART birth. Naturally conceived ART siblings were identified through the mother's information. Non-ART children were classified as being born to women who conceived with ovulation induction (OI)/IUI when there was an indication of infertility treatment on the birth certificate, but the woman did not link to the SART CORS; all others were classified as being naturally conceived.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study population included 135 051 ART children (78 362 singletons and 56 689 twins), 23 647 naturally conceived ART siblings (22 301 singletons and 1346 twins) and 9396 children born to women treated with OI/IUI (6597 singletons and 2799 twins) and 1 067 922 naturally conceived children (1 037 757 singletons and 30 165 twins). All study children were linked to their respective State birth defect registries to identify major defects diagnosed within the first year of life. We classified children with major defects as either chromosomal (i.e. presence of a chromosomal defect with or without any other major defect) or nonchromosomal (i.e. presence of a major defect but having no chromosomal defect), or all major defects (chromosomal and nonchromosomal). Logistic regression models were used to generate adjusted odds ratios (AORs) and 95% CI to evaluate the risk of birth defects due to conception with ART (using autologous oocytes and fresh embryos), and with and without the use of ICSI in the absence or presence of male factor infertility, with naturally conceived children as the reference. Analyses within the ART group were stratified by combinations of oocyte source (autologous, donor) and embryo state (fresh, thawed), with births from autologous oocytes and fresh embryos as the reference. Analyses limited to fresh embryos were stratified by oocyte source (autologous, donor) and the use of ICSI. Triplets and higher-order multiples were excluded.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 21 998 singleton children (1.9%) and 3037 twin children (3.3%) had a major birth defect. Compared to naturally conceived children, ART singletons (conceived from autologous oocytes, fresh embryos without the use of ICSI) had increased risks of a major nonchromosomal birth defect (AOR 1.18, 95% 1.05, 1.32), cardiovascular defects (AOR 1.20, 95% CI 1.03, 1.40), and any birth defect (AOR 1.18, 95% CI 1.09, 1.27). Compared to naturally conceived children, ART singletons conceived (from autologous oocytes, fresh embryos) with the use of ICSI, the risks were increased for a major nonchromosomal birth defect (AOR 1.30, 95% CI 1.16, 1.45 without male factor diagnosis; AOR 1.42, 95% CI 1.28, 1.57 with male factor diagnosis); blastogenesis defects (AOR 1.49, 95% CI 1.08, 2.05 without male factor; AOR 1.56, 95% CI 1.17, 2.08 with male factor); cardiovascular defects (AOR 1.28, 95% CI 1.10,1.48 without male factor; AOR 1.45, 95% CI 1.27, 1.66 with male factor); in addition, the risk for musculoskeletal defects was increased (AOR 1.34, 95% CI 1.01, 1.78 without male factor) and the risk for genitourinary defects in male infants was increased (AOR 1.33, 95% CI 1.08, 1.65 with male factor). Comparisons within ART singleton births conceived from autologous oocytes and fresh embryos indicated that the use of ICSI was associated with increased risks of a major nonchromosomal birth defect (AOR 1.18, 95% CI 1.03, 1.35), blastogenesis defects (AOR 1.65, 95% CI 1.08, 2.51), gastrointestinal defects (AOR 2.21, 95% CI 1.28, 3.82) and any defect (AOR 1.11, 95% CI 1.01, 1.22). Compared to naturally conceived children, ART singleton siblings had increased risks of musculoskeletal defects (AOR 1.32, 95% CI 1.04, 1.67) and any defect (AOR 1.15, 95% CI 1.08, 1.23). ART twins (conceived with autologous oocytes, fresh embryos, without ICSI) were at increased risk of chromosomal defects (AOR 1.89, 95% CI 1.10, 3.24) and ART twin siblings were at increased risk of any defect (AOR 1.26, 95% CI 1.01, 1.57). The 18% increased risk of a major nonchromosomal birth defect in singleton infants conceived with ART without ICSI (∼36% of ART births), the 30% increased risk with ICSI without male factor (∼33% of ART births), and the 42% increased risk with ICSI and male factor (∼31% of ART births) translates into an estimated excess of 386 major birth defects among the 68 908 singleton children born by ART in 2017.

LIMITATIONS, REASONS FOR CAUTION

In the SART CORS database, it was not possible to differentiate method of embryo freezing (slow freezing vs vitrification), and data on ICSI was only available in the fresh embryo ART group. In the OI/IUI group, it was not possible to differentiate type of non-ART treatment utilized, and in both the ART and OI/IUI groups, data were unavailable on duration of infertility.

WIDER IMPLICATIONS OF THE FINDINGS

The use of ART is associated with increased risks of a major nonchromosomal birth defect, cardiovascular defect and any defect in singleton children, and chromosomal defects in twins; the use of ICSI further increases this risk, the most with male factor infertility. These findings support the judicious use of ICSI only when medically indicated. The relative contribution of ART treatment parameters versus the biology of the subfertile couple to this increased risk remains unclear and warrants further study.

STUDY FUNDING/COMPETING INTEREST(S)

This project was supported by grant R01 HD084377 from the National Institute of Child Health and Human Development. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institute of Child Health and Human Development, or the National Institutes of Health, nor any of the State Departments of Health which contributed data. E.W. is a contract vendor for SART; all other authors report no conflicts.

TRIAL REGISTRATION NUMBER

N/A.

The effect of laser-assisted hatching on the methylation and expression pattern of imprinted gene IGF2/H19 in mouse blastocysts and offspring

PURPOSE

This study aimed to determine the effects of drilling and thinning treatment of laser-assisted hatching on the expression and methylation of imprinted gene IGF2/H19 in embryos and offspring.

METHODS

The prehatching blastocysts with treatment of drilling or thinning, or control prehatching blastocysts, were transplanted in surrogate uteri. The DNA methylation of IGF2/H19 imprinting control region (ICR) and the expression of IGF2 and H19 were respectively evaluated using bisulfite conversion-mediated sequencing and real-time PCR.

RESULTS

The drilling group showed a significant increase in the development rate of hatched blastocysts in comparison with the control and thinning group. DNA methylation level of IGF2/H19 ICR of hatched blastocysts in the thinning group was 27.33% in comparison with the 38.67% and 36% observed in the control and drilling group. The thinning treatment increased the DNA methylation level of IGF2/H19 ICR in the placenta in comparison with the control and drilling group. The drilling and thinning treatment decreased the expression level of H19 mRNA in prehatching and hatched blastocysts as well as placenta, while a significant increase in the expression level of H19 mRNA of offspring was observed in the thinning group. The thinning treatment increased the expression level of IGF2 mRNA of prehatching blastocysts and offspring and a significant decrease in placenta, while the drilling treatment resulted in a significant increase in the expression level of IGF2 mRNA of hatched blastocysts and placenta.

CONCLUSION

These observations suggested that drilling used for hatching of in vitro cultured mouse blastocysts may improve the production of offspring.

Single-cell DNA methylation sequencing reveals epigenetic alterations in mouse oocytes superovulated with different dosages of gonadotropins

BACKGROUND

Epigenetic abnormalities caused by superovulation have recently attracted increasing attention. Superovulation with exogenous hormones may prevent oocytes from establishing an appropriate epigenetic state, and this effect may extend to the methylation programming in preimplantation embryos, as de novo DNA methylation is a function of developmental stage of follicles and oocyte size. Follicle-stimulating hormone (FSH) and human menopausal gonadotropin (hMG) are common gonadotropins used for superovulation, and appropriate concentrations of these gonadotropins might be necessary. However, no systematic study on the effects of DNA methylation alterations in oocytes associated with superovulation with different dosages of FSH/hMG at the single-cell level has yet been reported. In the current study, different dosages of FSH/hMG combined with human chorionic gonadotropin (hCG) were used in female mice to generate experimental groups, while naturally matured oocytes and oocytes superovulated with only hCG were respectively used as controls. Single-cell level DNA methylation sequencing was carried out on all these matured oocytes.

RESULTS

In this study, we revealed that the genome-wide methylation pattern and CG methylation level of the maternal imprinting control regions of all mature oocytes were globally conserved and stable. However, methylation alterations associated with superovulation were found at a specific set of loci, and the differentially methylated regions (DMRs) mainly occurred in regions other than promoters. Furthermore, some of the annotated genes in the DMRs were involved in biological processes such as glucose metabolism, nervous system development, cell cycle, cell proliferation, and embryo implantation and were altered in all dosages of FSH/hMG group (for example, Gfod2 and SYF2). Other genes were impaired only after high gonadotropin dosages (for instance, Sox17 and Phactr4).

CONCLUSIONS

In conclusion, the current study addressed the effects of superovulation on DNA methylation from the perspective of different dosages of gonadotropins at the single-cell level. We found that the genome-wide DNA methylation landscape was globally preserved irrespective of superovulation or of the kind and dosage of gonadotropins used, whereas the methylation alterations associated with superovulation occurred at a specific set of loci. These observed effects reflect that superovulation recruits oocytes that would not normally be ovulated or that have not undergone complete epigenetic maturation. Our results provide an important reference for the safety assessment of superovulation with different dosages of gonadotropins. However, it should be noted that this study has some limitations, as the sample number and library coverage of analyzed oocytes were relatively low. Future studies with larger sample sizes and high-coverage libraries that examine the effects of superovulation on embryo development and offspring health as well as the underlying mechanisms are still needed.

Severity of congenital heart defects associated with assisted reproductive technologies: Case series and review of the literature

OBJECTIVE

Assisted reproductive technology (ART) has been associated with a higher incidence of congenital anomalies, including a specific increase in the rate of congenital heart defects (CHD). In this study, the rate of CHD in pregnancies resulting from ART at a single high-risk pregnancy referral center are compared to the published literature.

METHODS

Pregnancies were screened by fetal echocardiography for the indication of ART over a 2-year period. CHD were classified as either mild or severe based on the need for postnatal surgical intervention. Results were compared to findings from a literature review of studies examining CHD in pregnancies resulting from ART since 1980.

RESULTS

Over the course of two years, 363 fetuses in 264 pregnancies from our cohort were screened for CHD. The incidence of mild CHD in fetuses from ART pregnancies was 2.75% (10 out of 363 fetuses). None of the affected fetuses had severe CHD. Review of the literature yielded 20 studies since 1980 that examined CHD in pregnancies resulting from ART. Composite data from the studies was described based on characterization of severity of the CHD anomalies. The incidence of mild CHD in ART pregnancies was 2.2%, compared to 1% in non-ART pregnancies (out of 332,157 infants). The incidence of severe CHD in ART pregnancies and naturally conceived pregnancies was 1.4% and 1.2%, respectively (out of 661,455 infants). The incidence of unspecified CHD in ART pregnancies was 1.8%, compared to 1% in naturally conceived pregnancies (out of 1,593,277 infants).

CONCLUSION

The greatest increase in risk appears to be for mild CHD (nonsurgical), which may inform counseling of patients prior to use of assisted reproductive technologies.

Congenital Malformations in Infants of Mothers Undergoing Assisted Reproductive Technologies: A Systematic Review and Meta-analysis Study

Objectives

This meta-analysis aimed to evaluate congenital malformations in infants conceived by assisted reproductive techniques (ART), compared with infants conceived spontaneously.

Methods

In this study, available resources searched to find relevant articles included PubMed, ScienceDirect, Scopus, Google Scholar, Cochrane, ProQuest, Iranmedex, Magiran, and Scientific Information Database. After extracting the necessary information from evaluated articles, meta-analysis on the articles’ data was performed using Stata version 11.2.

Results

In this study, from a total of 339 articles, extracted from the initial investigation, ultimately 30 articles were selected for meta-analysis that assessed the use of ART on the risk of congenital abnormalities and some birth complications on 5 470 181 infants (315 402 cases and 5 154 779 controls). The odds ratio (95% confidence interval [CI]) for low birth weight was 1.89 (95% CI, 1.36 to 2.62), preterm labor 1.79 (95% CI, 1.21 to 2.63), cardiac abnormalities 1.43 (95% CI, 1.27 to 1.62), central nervous system abnormalities 1.36 (95% CI, 1.10 to 1.70), urogenital system abnormalities 1.58 (95% CI, 1.28 to 1.94), musculoskeletal disorders 1.35 (95% CI, 1.12 to 1.64), and chromosomal abnormalities in infants conceived by ART was 1.14 (95% CI, 0.90 to 1.44), which were all statistically significant, except chromosomal abnormalities.

Conclusions

The risk of congenital abnormalities and some birth complications were significantly higher in ART than normal conception, while chromosomal abnormalities were not; therefore, the application of ART should be selected individually for patients by detailed assessment to reduce such risks in the population.

Effects of three-area laser-assisted zona thinning in 8-cell human embryos on pregnancy outcomes in vitro fertilization

Objective

This study conducted a preliminary examination of the effects of three-area laser-assisted zona thinning (LAZT) during the cleavage stage of embryo development on the hatching process in human in vitro fertilization-embryo transfer (IVF-ET) with subjects of advanced female age or frozen-thawed (FT) embryos.

Methods

Eight-cell stage embryos were treated with LAZT in three areas of the zona pellucida at 120° intervals. The control group was embryos without LAZT. Of the 72 consecutive fresh cycles and the 28 FT embryo transfer cycles, the patients in 55 fresh cycles and 17 FT cycles declined LAZT, and those cycles were defined as the control group.

Results

In the fresh cycles, the pregnancy rates were similar in the LAZT and control groups. However, in the FT cycles, the pregnancy rate was significantly higher in the LAZT group than in the control group (45.5% in the LAZT group vs. 23.5% in the control group, p<0.05).

Conclusion

These results show that multi-area LAZT resulted in significantly improved pregnancy outcomes in human 8-cell embryos compared to controls.

Superovulation alters DNA methyltransferase protein expression in mouse oocytes and early embryos

PURPOSE

DNA methylation is an epigenetic mechanism that plays critical roles during mammalian oocyte and preimplantation embryo development. It is achieved by adding a methyl group to the fifth carbon atom of cytosine residues within cytosine-phosphate-guanine (CpG) and non-CpG dinucleotide sites using DNA methyltransferase (DNMT) enzymes for de novo and maintenance methylation processes. DNMT1, DNMT3A, and DNMT3B play important roles in establishing methylation of developmentally related genes in oocytes and early embryos. The purpose of this study is to identify the effect of superovulation on the expression and subcellular localizations of these three DNMT enzymes in the mouse oocytes and early embryos.

METHODS

Three groups composed of control, normal dose [5 IU pregnant mare serum gonadotropin (PMSG) and 5 IU human chorionic gonadotropin (hCG)], and high dose [7.5 IU PMSG and 7.5 IU hCG] were created from 4-5-week-old female BALB/c mice. The relative expression and subcellular localizations of the DNMT proteins in the control and experiment groups have been characterized by using immunofluorescence staining subsequently analyzed in detailed.

RESULTS

DNMT1, DNMT3A, and DNMT3B protein expression in the germinal vesicle and metaphase II oocytes and in one-cell and two-cell embryos differed significantly when some of the normal- and high-dose groups were compared with the control counterparts.

CONCLUSION

This study has demonstrated for the first time that superovulation alters expression levels of the DNMT proteins, a finding that indicates that certain developmental defects in superovulated oocytes and early embryos may result from impaired DNA methylation processes.

Multiple pregnancies achieved with IVF/ICSI and risk of specific congenital malformations: a meta-analysis of cohort studies

Studies comparing risk of specific congenital malformations (CM) between multiple pregnancies resulting from IVF/intracytoplasmic sperm injection (ICSI) and those conceived naturally report conflicting results; furthermore, there is a lack of a complete overview. This meta-analysis aimed to address which types of CM are increased in IVF/ICSI multiple pregnancies compared with those conceived naturally. All studies testing the association between IVF/ICSI multiple pregnancies and specific CM identified in various databases were considered. The literature search yielded 856 records, of which 21 cohort studies were included for analysis. Overall, multiple pregnancies achieved with IVF/ICSI experienced a significantly higher risk of chromosomal defects (relative risk [RR] = 1.36; 95% confidence interval [CI]: 1.04-1.77), urogenital (RR = 1.18; 95% CI: 1.03-1.36) and circulatory (RR = 1.22; 95% CI: 1.01-1.47) system malformations. However, the remaining specific CM, such as cleft lip and/or palate, eye, ear, face and neck, respiratory, musculoskeletal, nervous and digestive system malformations, were similar in the two groups. No substantial heterogeneity was observed for most outcomes except for digestive (P = 0.094; I² = 38.3%) and circulatory (P = 0.070; I² = 35.2%) system malformations. These findings provide additional information on risks of IVF/ICSI for use when counselling patients.

Which type of congenital malformations is significantly increased in singleton pregnancies following after in vitro fertilization/intracytoplasmic sperm injection: a systematic review and meta-analysis

It is inconclusive nowadays for which type of congenital malformations(CMs) is increased in singleton pregnancies following after in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI) compared with those after spontaneous conception; furthermore, a complete overview is missing. We conducted a meta-analysis of cohort studies to assess the risk of specific CMs associated with IVF/ICSI singleton pregnancies. Unrestricted searches were conducted, with an end date parameter of 1 June 2017, of PubMed, Embase, Google Scholar, Cochrane Libraries, and Chinese databases. Either a fixed- or a random-effects model was used to calculate the overall combined risk estimates. Subgroup and sensitivity analyses were performed to explore potential heterogeneity moderators when significant heterogeneity was observed. Sixteen cohort studies with a total of 129,648 IVF/ICSI and 5,491,949 spontaneously conceived singleton births fulfilled the inclusion criteria. The IVF/ICSI singleton pregnancies had a significantly increased risk of cleft lip and/or palate (OR = 1.34 [95% CI: 1.07–1.69]; I² = 0%), eye, ear, face and neck (odd ratios [OR] = 1.20 [95% CI: 1.04–1.39]; I² = 15%), chromosomal (OR = 1.23 [95% CI: 1.07–1.40]; I² = 32%), respiratory (OR = 1.28 [95% CI: 1.01–1.64]; I² = 37%), digestive (OR = 1.46 [95% CI: 1.29–1.65]; I² = 0%), musculoskeletal (OR = 1.47 [95% CI: 1.25–1.72]; I² = 64%), urogenital (OR = 1.43 [95% CI: 1.18–1.72]; I² = 62%), and circulatory (OR = 1.39 [95% CI: 1.23–1.58]; I² = 46%) system malformations. Relevant heterogeneity moderators have been identified by subgroup analysis. Sensitivity analysis yielded consistent results. No evidence of publication bias was observed. In conclusion, the IVF/ICSI singleton pregnancies are associated with higher risks for most specific CMs. Clinicians should provide appropriate information to counseling IVF/ICSI patients.

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.

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.

Effect of semen quality on human sex ratio in in vitro fertilization and intracytoplasmic sperm injection: an analysis of 27,158 singleton infants born after fresh single-embryo transfer

OBJECTIVE

To evaluate the effect of semen quality on human sex ratio in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENT(S)

A total of 27,158 singleton infants born between 2007 and 2012 after fresh single-embryo transfer.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Proportion of male infants among liveborn infants.

RESULT(S)

There were 14,996 infants born after IVF, 12,164 infants born after ICSI with ejaculated sperm, and 646 infants born after ICSI with nonejaculated sperm. The sex ratio of IVF was 53.1% (95% confidence interval [CI], 52.3-53.9); the sex ratio of ICSI with ejaculated and nonejaculated sperm demonstrated as statistically significant reduction (48.2%; 95% CI, 47.3-49.1 and 47.7%; 95% CI, 43.8-51.6, respectively). In IVF, lower sperm motility, including asthenozoospermia (sperm motility <40%), was associated with a statistically significantly lower sex ratio compared with normal sperm (51.0%; 95% CI, 48.6-53.3 vs. 53.4%; 95% CI, 52.5-54.3). In ICSI with ejaculated sperm, there was no association between sperm motility and sex ratio. Sperm concentration was not associated with sex ratio in both IVF and ICSI.

CONCLUSION(S)

In IVF, lower sperm motility was associated with a statistically significant reduction in sex ratio; ICSI with either ejaculated or nonejaculated sperm was associated with a statistically significant reduction in sex ratio regardless of semen quality.