Perinatal & Pediatric
The association of maternal intellectual and developmental disabilities with severe maternal morbidity in California Catherine Psaras* Catherine Psaras Gretchen Bandoli Rita Ryu
Background. Intellectual and developmental disabilities (IDD) involve cognitive and adaptive deficits beginning before age 18–22. Fertility rates among people with IDD are rising, but they still face health disparities during pregnancy. This study examined the relationship between IDD subtypes and severe maternal morbidity (SMM) and identified factors mediating SMM in women with IDD. Methods. This population-based study analyzed linked California data (2007–2021), including birth, infant death, discharge, emergency department, and ambulatory surgery center records. Singleton births to women with preexisting IDD (autism spectrum disorder (ASD), cerebral palsy (CP), intellectual disabilities (ID), chromosomal abnormalities, and other IDD) were compared to those without IDD, with disabilities identified using diagnosis codes. SMM was defined as a composite of 21 diagnostic indicators from conception to 42 days postpartum. We estimated relative risks and the proportion of the total effect of IDD on SMM mediated by pre-pregnancy characteristics. Results. The data included 6,430,534 singleton pregnancies from 2007–2021. 4,713 pregnancies were among women with IDD (non-mutually exclusive subtypes: ASD: 458; CP: 1019; ID: 1817; chromosomal abnormalities: 1571; other IDD: 600). All IDD subtypes were associated with SMM (any IDD: 2.88 [95% CI: 2.52, 3.29]). The strongest mediators were anxiety or depression (10%; 95% CI: 3%–17%) and epilepsy (12%; 95% CI: 5%–19%). There was heterogeneity by IDD subtype in the total effect and mediation analyses (ASD 2.66 [1.68, 4.22]; ID 3.35 [2.63, 4.27]; CP 2.33 [1.69, 3.23]; chromosomal abnormalities 2.29 [1.77, 2.96]; other IDD 4.60 [3.43, 6.17]). Discussion. There was excess risk of SMM among women with IDD, some of which was mediated through pre-pregnancy characteristics such as epilepsy and mental health diagnoses. Quantifying excess risk and associated mediating pathways can inform intervention strategies.