Periconceptional Hormonal Contraception Use and Autism Spectrum Disorder in the Study to Explore Early Development.

Researchers studied whether using hormonal birth control around the time of conception might be linked to autism in children. They found a possible weak connection when birth control was used during early pregnancy, but this result was not statistically significant. Using birth control before pregnancy showed no association with autism. The study had limitations including low numbers of women using contraception during pregnancy and potential memory bias.

This population-based case-control study from the Study to Explore Early Development (SEED) examined whether hormonal contraception use around conception is associated with autism spectrum disorder (ASD) in offspring. Among 5,210 participants, 9.9% discontinued hormonal contraception before pregnancy and 2.3% continued use during pregnancy. The study found a suggestive but statistically non-significant association between hormonal contraception use during pregnancy and ASD (adjusted OR 1.38, 95% CI 0.93-2.05). No association was found with use prior to pregnancy (adjusted OR 1.02, 95% CI 0.84-1.25).

The authors note that results were imprecise and may be affected by recall bias and unmeasured confounding factors.

Findings do not provide strong evidence for or against hormonal contraception as an ASD risk factor. The suggestive association during pregnancy requires replication in larger studies. Current evidence insufficient to change clinical recommendations regarding contraception counseling.

Results were imprecise due to small numbers using contraception during pregnancy. Potential recall bias and unmeasured confounding by pregnancy planning behaviors and health factors. Wide confidence intervals limit interpretation of findings.

Prior studies report associations between periconceptional exposure to natural and synthetic oestrogen and progesterone and autism spectrum disorder (ASD). Hormonal contraception contains synthetic forms of one or both hormones. Although hormonal contraception is highly effective when consistently used, unintended pregnancy can occur with irregular use. Given the popularity of hormonal contraception, foetal exposure in utero is possible, yet the potential consequences are unknown.

We investigated the association between periconceptional hormonal contraception use and the development of ASD in offspring. We analysed data from the Study to Explore Early Development (SEED), a population-based case-control study conducted in select US states, from 2007 to 2020. Children with and without ASD were identified from clinical/education sources and vital records, respectively, and enrolled at ages 2.5-5 years. We confirmed the ASD case status by in-person developmental assessment.

We assessed hormonal contraception via a structured interview. We assessed the associations between ASD and hormonal contraception exposure separately for contraception discontinued in the 3 months prior to pregnancy and contraception continued during pregnancy using logistic models to estimate odds ratios (OR) adjusted for biological mother age, education, parity, pre-pregnancy body mass index (BMI), and presence of gynaecologic conditions and 95% confidence intervals (CI). Of 5210 participants, 9.9% reported discontinuing hormonal contraception use before pregnancy and 2.3% reported continuing use during pregnancy. A suggestive association was found between ASD and hormonal contraception use during pregnancy (aOR 1.38,95% CI 0.93, 2.05).

There was no association with use prior to pregnancy (aOR 1.02, 95% CI 0.84, 1.25). Discontinuation of hormonal contraception prior to conception was not associated with ASD. The prevalence of hormonal contraception use during pregnancy was low. Results were imprecise and may be impacted by recall bias and unmeasured confounding by indication and health behaviours related to planning pregnancy.