Assisted reproductive technology and childhood morbidity: a longitudinal cohort study

The rationale, design of the Assisted reproductive technology cohort nested in a pre-pregnancy family cohort (APP-Cohort)

INTRODUCTION

Infertility has become a major global issue due to the trend of delaying marriage and advanced maternal age. Family/Birth cohort studies are essential for exploring ways to enhance health outcomes at both the individual and societal levels. However, there is a shortage of cohorts that include families who have utilized assisted reproductive technology (ART), particularly initiated at the early stages before pregnancy. The Assisted Reproductive Technology Cohort (APP-Cohort) is a prospective study aiming to investigate the epidemiology and risk factors of adverse gestational outcomes and other health issues in couples who have conceived through ART or naturally.

METHODS

The cohort study's baseline survey commenced in January 2022 at several locations in Beijing, and enrollment is currently in progress. Both spouses filled out a questionnaire covering demographic, socio-economic, and various modifiable risk factors to gather information on their lifestyle. Physical examinations and biochemical tests were carried out, alongside regular yearly health check-ups throughout pregnancy and childhood. The survey data will be connected to electronic medical records to compile health information on the couples, newborns, and children.

DISCUSSION

The APP-Cohort study collected data from both wives and husbands before conception, allowing for early assessment of environmental risk factors for maternal and offspring health. With a focus on various types of risk factors such as genetic, environmental, and shared familial traits, the ongoing follow-up of this study will enable researchers to evaluate and distinguish the impacts of these factors on pregnancy outcomes, perinatal health, and children's health for individuals conceived naturally versus those conceived through ART. By utilizing practical experience and advanced mathematical analysis of the extensive data, the APP-Cohort study will provide valuable insights to promote the administration and success rate of ART in China.

Immune profiling of ART-conceived children in Kazakhstan: a case-control study

Objective

The increasing use of assisted reproductive technologies (ART) has led to a growing interest in the health outcomes of offspring. However, the impact of ART on the immune system of children remains poorly understood. While only two publications were found, their findings contradict each other and did not consider other risk factors in their analysis except for ART use. Therefore, this study aimed to examine the potential impact of ART on the immune system of offspring.

Methods

A case-control study was conducted in Kazakhstan to investigate the immune system of ART-conceived children compared to those conceived naturally (NC). The study included participants who met certain criteria, such as having undergone a successful ART program resulting in the birth of either a single or multiple pregnancies. Patients who used donor oocytes/sperm, intrauterine insemination, or surrogacy were excluded. Anamnesis data were collected from children in both groups, and laboratory measurements were performed and analyzed using IBM SPSS Statistic 26.

Results

A total of 120 children conceived by ART and 132 NC children under the age of five were included in our study. We observed that compared with NC group, ART children had lower IgA and IgG levels (p < 0.001), absolute lymphocytosis, high levels of active T-lymphocytes (p = 0.001), and pathological T-helper levels (p = 0.004). Therefore, the clinical presentation of respiratory diseases was lower in ART group. Children born after frozen embryo transfers showed significantly higher levels of T-cytotoxic and active T-lymphocytes compared to children born after fresh embryo transfers (p = 0.007 and p = 0.020, respectively). We utilized ordinal logistic regression to control for confounding variables such as multiple pregnancy, cesarean section, premature birth, and breastfeeding. Despite this, the significant impact of ART on immunogram parameters persisted, indicating the independent and influential nature of ART or other unaccounted factors.

Assisted Reproductive Technology During COVID-19: A Population-Based Study Of Pregnancy Outcomes

We assessed the impact of the COVID-19 pandemic on the pregnancy outcomes of patients who used assisted reproductive technology. We conducted a population-based cohort study of 443,101 patients who conceived naturally or with assisted reproductive technology between December 2015 and July 2021 and had a delivery in hospitals of Quebec, Canada. The main exposure measure was use of assisted reproductive technology before or during the pandemic. Outcomes included preeclampsia, preterm birth, and other pregnancy complications. We used adjusted log-binomial regression models to estimate risk ratios (RR) and 95% confidence intervals (CI) for the association of assisted reproductive technology with adverse pregnancy outcomes compared with natural conception before vs. during the pandemic. In secondary analyses, we examined the association of COVID-19 infection with pregnancy outcomes among women who used assisted reproductive technology. Compared with natural conception, assisted reproductive technology was associated with an increased risk of preeclampsia (RR 1.43; 95% CI 1.21-1.68), preterm birth (RR 2.07; 95% CI 1.84-2.33), and low birth weight (RR 1.94; 95% CI 1.72-2.20) during the pandemic. However, the same risks were also present before the pandemic. Compared with no infection, COVID-19 infection was not associated with adverse outcomes among women who conceived with assisted reproductive technology. This study suggests that the COVID-19 pandemic did not significantly impact the pregnancy outcomes of women who underwent assisted reproductive procedures in Quebec. The findings are reassuring for patients concerned about the potential reproductive effects of the pandemic.

Assisted Reproductive Technology and Cardiovascular Outcomes in Parents and Offspring

BACKGROUND

The impact of assisted reproductive technology (ART) on the cardiovascular system is unclear.

METHODS

We conducted a retrospective longitudinal cohort study of 1,001,593 pregnancies conceived naturally or through ART from 2008 to 2019 in Québec to assess the association of ART with cardiovascular disease in families. The exposure measure was ART. The outcome included severe maternal cardiovascular morbidity, congenital heart defects in offspring, and long-term risk of cardiovascular hospitalisation in mothers, fathers, and offspring during 11 years of follow-up. We estimated the association between ART and cardiovascular outcomes with the use of adjusted log-binomial regression (risk ratio, 95% confidence interval [CI]) and Cox proportional hazards regression models (hazard ratio [HR]).

RESULTS

Compared with natural conception, ART was associated with 2.04 times the risk of severe cardiovascular morbidity in mothers (95% CI 1.86-2.23) and 1.38 times the risk of congenital heart defects in offspring (95% CI 1.26-1.50). ART was not associated with the risk of maternal cardiovascular hospitalisation following pregnancy (HR 1.03, 95% CI 0.88-1.21). However, ART was associated with an increased risk of paternal cardiovascular hospitalisation (HR 1.24, 95% CI 1.11-1.38) and offspring cardiovascular hospitalisation (HR 1.27, 95% CI 1.01-1.61), mainly due to an increased risk of hypertension.

CONCLUSIONS

ART is associated with only a small increase in the risk of cardiovascular complications in families. Parents and offspring may be reassured that ART likely has no major impact on the cardiovascular system.

DNA Methylation in Offspring Conceived after Assisted Reproductive Techniques: A Systematic Review and Meta-Analysis

Background: In the last 40 years, assisted reproductive techniques (ARTs) have emerged as potentially resolving procedures for couple infertility. This study aims to evaluate whether ART is associated with epigenetic dysregulation in the offspring. Methods. To accomplish this, we collected all available data on methylation patterns in offspring conceived after ART and in spontaneously conceived (SC) offspring. Results. We extracted 949 records. Of these, 50 were considered eligible; 12 were included in the quantitative synthesis. Methylation levels of H19 CCCTC-binding factor 3 (CTCF3) were significantly lower in the ART group compared to controls (SMD −0.81 (−1.53; −0.09), I² = 89%, p = 0.03). In contrast, H19 CCCTC-binding factor 6 (CTCF6), Potassium Voltage-Gated Channel Subfamily Q Member 1 (KCNQ1OT1), Paternally-expressed gene 3 (PEG3), and Small Nuclear Ribonucleoprotein Polypeptide N (SNRPN) were not differently methylated in ART vs. SC offspring. Conclusion: The methylation pattern of the offspring conceived after ART may be different compared to spontaneous conception. Due to the lack of studies and the heterogeneity of the data, further prospective and well-sized population studies are needed to evaluate the impact of ART on the epigenome of the offspring.