The relationship between parental infertility and autism risk in children

summary: A study of 1.3 million children found that children born to parents with fertility problems had a slightly higher risk of developing autism spectrum disorder (ASD). The research suggests that the risk of developing autism spectrum disorder is increased in children of parents previously diagnosed with infertility, regardless of whether fertility treatments were involved.

The study also highlights the role of obstetric factors such as multiple pregnancies and preterm births in mediating this association. More research is needed to explore the mechanisms behind this association.

Key facts:

1. Children born to parents with infertility problems have a slightly increased risk of developing autism spectrum disorder (ASD).
2. This increased risk is independent of the use of fertility treatments.
3. Birth factors, such as having twins or preterm birth, mediate a significant portion of the association between parental infertility and ASD.

source: Queen’s University

One in 50 Canadian children has autism spectrum disorder (ASD), a neurodevelopmental condition that can affect sensory processing, communication, and emotional and behavioral regulation. However, the causes of this lifelong disorder remain unclear and likely involve a combination of genetic and environmental factors.

A new study published today in The JAMA Network is open Reports on a cohort study of more than 1.3 million children born in Ontario between 2006 and 2018. The results suggest that children born to individuals diagnosed with fertility problems are slightly more likely to develop autism spectrum disorder.

With infertility diagnoses on the rise – it is estimated that one in six couples face this challenge – publicly funded fertility programs have also increased access to fertility treatment in Canada. Alongside this growth there is a need to answer questions about health outcomes for mothers and children who receive fertility treatment.

The newly published study, led by Maria Velez (Obstetrics and Gynecology), evaluated pregnancy and infant characteristics in relation to infertility, its treatments, and autism spectrum disorder using existing linked administrative health data.

Children were classified by method of conception, namely unassisted conception (86.5 percent), infertility without fertility treatment or subfertility (10.3 percent), ovulation induction or intrauterine insemination (1.5 percent), and in vitro fertilization or intrauterine sperm injection. Cytoplasm (1.7%). .

Starting at 18 months, the children were followed for 5 to 11 years, and 22,409 children were diagnosed with ASD, or 1.6% of the total. Because not all children were followed at the same time, the incidence of autism spectrum disorder was calculated in person-years — a type of measurement that takes into account the number of people in the study and the amount of time each person spends in the study.

For example, a study that follows 1,000 people for one year each will have data for 1,000 people per year.

In this study, the incidence of ASD was 1.9 per 1,000 person-years among children in the first group, and higher among children in the subfertility (2.5) and after fertility treatment (2.7) groups.

The results suggest that there is a small increased risk of developing autism spectrum disorder in children born to patients previously diagnosed with infertility, regardless of whether they have received fertility treatment.

“In addition, our results also show that certain birth factors, such as having twins or triplets, or preterm birth, significantly mediate the association between parental infertility and autism spectrum disorder,” says Dr. Velez.

According to the authors, the findings support continued efforts to reduce the chances of multiple pregnancies and preterm birth after fertility treatments, as well as the importance of providing early care plans to pregnant patients who have received such treatments, with the aim of reducing adverse pregnancies. Results in this population.

Further studies are needed to understand some of the mechanisms by which a parental diagnosis of infertility, independent of fertility treatment, may be associated with a slightly increased risk of ASD in the child.

“For example, we need more precise details about the diagnosis of underlying infertility, parental factors, and whether the egg(s) or sperm is from a parent or a donor, among other factors,” Dr. Velez explains.

About autism research news

author: Catarina Chagas
source: Queen’s University
communication: Catarina Chagas – Queen’s University
picture: Image credited to Neuroscience News

Original search: Open access.
“Infertility and the Risk of Autism Spectrum Disorder in Children” by Maria Velez et al. The JAMA Network is open

a summary

Infertility and the risk of autism spectrum disorder in children

Importance

Previous studies on the risk of childhood autism spectrum disorder (ASD) after fertility treatment have not taken into account infertility itself or the mediating effect of obstetric and neonatal factors.

objective

To evaluate the relationship between infertility and its treatments on the risk of developing autism spectrum disorder and the mediating effect of selected adverse pregnancy outcomes on this association.

Design, setting and participants

This was a population-based cohort study in Ontario, Canada. All participants had singleton and multiple live births at 24 weeks or more of gestation from 2006 to 2018. Data from October 2022 to October 2023 were analyzed.

Exposure

Exposure was mode of conception, namely (1) unassisted conception, (2) infertility without fertility treatment (i.e. subfertility), (3) ovulation induction (OI) or intrauterine insemination (IUI), or (4) in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI).

Main outcome and measures

The outcome of the study was a diagnosis of autism spectrum disorder at the age of 18 months or older. Cox regression models generated hazard ratios (HR) adjusted for maternal and infant characteristics. Mediation analysis also explained the separate effect of (1) preeclampsia, (2) cesarean section, (3) multifetal pregnancy, (4) preterm birth at <37 weeks, and (5) severe neonatal morbidity.

results

A total of 1,370,152 children (703,407 boys (51.3%)) were included: 1,185,024 (86.5%) with unassisted conception, 141,180 (10.3%) with parental subfertility, 20,429 (1.5%) after IVF or in vitro fertilization. Uterine and 23,519 (1.7%) after IVF or ICSI. Individuals with subfertility or fertility treatment were older and resided in high-income areas; The mean (SD) age for each group was as follows: 30.1 (5.2) years in the unassisted conception group, 33.3 (4.7) years in the fertility group, 33.1 (4.4) years in the OI or IUI group, and 35.8 (4.9) ) Years in the IVF or ICSI group.

The incidence of autism spectrum disorder was 1.93 per 1,000 person-years among children in the unsupported pregnancy group. For the latter, the adjusted HRs for ASD were 1.20 (95% CI, 1.15-1.25) in the fertility group, 1.21 (95% CI, 1.09-1.34) after OI or IUI, and 1.16 (95% CI, −1.04). 1.28) After artificial insemination or ICSI. Obstetric and neonatal factors appear to mediate a significant proportion of the above association between mode of conception and ASD risk. For example, after in vitro fertilization or ICSI, the rates of cesarean delivery were 29%, multifetal pregnancies were 78%, preterm birth was 50%, and rates of severe neonatal morbidity were 25%.

Conclusions and relevance

In this cohort study, a slightly increased risk of ASD was observed in children born to infertile subjects, which appears to be partly mediated by certain obstetric and neonatal factors. To improve the child’s neurodevelopment, strategies should explore these other factors in infertile individuals, even among those who are not receiving fertility treatment.