Autistic traits among women linked to increased preterm births

Credit: Unsplash / Luma Pimentel

Maternal autistic traits are positively associated with increased risk of adverse birth outcomes among expectant mothers, according to new data.

A cohort analysis from a team of Japan-based investigators reported that adverse outcomes such as very preterm births are up to 16% more likely among women with higher scores on the 10-item Autism-Spectrum Quotient Japanese version (AQ-J10). The findings put emphasis on the need for improved, comprehensive care strategies for women with a high level of autistic traits who may face antenatal psychological distress.

Led by Mariko Hosozawa, MD, PhD, of the Institute of Global Health Policy Research in the Bureau of International Health Cooperation at the National Center for Global Health and Medicine in Toyama, investigators sought to analyze the association between maternal autistic traits and the risk of adverse birth outcomes among the general population through a prospective cohort study. Prior research had indicated an increased risk of significant health disparities during pregnancy among women diagnosed with autism spectrum disorder (ASD);both distress for the expecting mother and adverse birth outcomes including preterm births and children born small for gestational age have been tied to the neurodevelopmental condition.

“It has been reported that individuals who have a high level of subclinical autistic traits may share similar genetic features and social and psychological difficulties with those diagnosed with ASD,” Hosozawa and colleagues wrote. “Given that women with an elevated level of autistic traits are less likely to receive a formal diagnosis than men, which may create further challenges in gaining support, there is a need to investigate the association between maternal autistic traits in the general population and adverse birth outcomes.”

The investigators conducted their analysis using mothers from a nationwide, multicenter, prospective birth cohort called the Japan Environmental Children’s Study; the expecting mothers were previously recruited for the cohort between January 2011 – March 2014. They sought primary outcome measures of preterm births (defined as <37 weeks’ gestation) and neonates born small for gestational age via medical records, as well as counts of very preterm birth (<32 weeks) and moderate-to-late preterm birth (32 – 36 weeks).

Regarding autistic traits, Hosozawa and colleagues used self-reported outcomes via the short-form AQ-J10, with scores of ≥7 indicating the clinical range for ASD, during expectant mothers’ second and third trimesters.

The analysis included 87,687 women; mean age was 31.2 years old. Though 2350 (2.7%) participants scored ≥7 on their AQ-J10 scores, only 18 (0.02%) were diagnosed with ASD. Mean score was 2.8 (SD, 1.7).

Investigators observed a significantly positive association between higher rates of autistic traits and increased risk of all birth outcomes:

• Preterm births (relative risk [RR] per 1-SD increase, 1.06; 95% CI, 1.03 – 1.09)
• Moderate-to-late preterm births (RR, 1.05; 95% CI, 1.01 – 1.08)
• Very preterm births (RR, 1.16; 95% CI, 1.06 – 1.26)
• Child born small for gestational age (RR, 1.11; 95% CI, 1.04 – 1.19)

“The risks of all birth outcomes were higher with a higher level of maternal autistic traits; for example, compared with women below the clinical range, women within the clinical range had greater risk of preterm births, moderate-to-late preterm births, very preterm births, and a child born small for gestational age,” Hosozawa and colleagues wrote. “To our knowledge, this is the first study to examine the association between maternal autistic traits and adverse birth outcomes in the general population.”

The team additionally observed that the associated adverse pregnancy outcomes among women with autistic traits may have been exacerbated by the poor rate of actual ASD diagnoses. “Receiving a formal diagnosis has been reported to be associated with increased access to appropriate support and health care, which could have protected women against very preterm births in the previous study,” they wrote. “The present study’s results show that women with a high level of autistic traits, particularly those within the clinical range and without a formal diagnosis, may have a high risk of adverse birth outcomes and require more attention and support during pregnancy.”

Though the findings are limited by factors of unmeasured confounders driving any genetic-based risk of poor pregnancy outcomes among women with autistic traits, the data were enough to warrant further research into the heightened risk of preterm births and small newborn sizes among women with autism.

“Health care practitioners should acknowledge the significant perinatal health disparity experienced by women with a high level of autistic traits, particularly those with autistic traits in the clinical range,” they concluded. “Comprehensive antenatal care including the assessment of antenatal psychological distress and offering timely and tailored support that meets the needs of women should be provided inclusively regardless of whether a formal diagnosis of ASD is received.”

References

^{Hosozawa M, Cable N, Ikehara S, et al. Maternal Autistic Traits and Adverse Birth Outcomes. JAMA Netw Open. 2024;7(1):e2352809. doi:10.1001/jamanetworkopen.2023.52809}