Do women with polycystic ovary syndrome and their children have elevated rates of autism? An electronic health records study in the UK
Elevated levels of prenatal testosterone may increase the risk for autism spectrum conditions (autism). There is also an association between autism and polycystic ovary syndrome (PCOS) in women with autism and mothers with a child with autism. Given that PCOS is also associated with elevated prenatal and circulating testosterone, taken together, hyperandrogenism may be involved in the development of autistic traits in women with PCOS and their children. This study sought to the magnitude of the association between these two conditions, by examining the prevalence of autism in women with PCOS and the prevalence of PCOS in women with autism, and determining the risk of developing autism in first-born children of women with PCOS.
Using electronic health records obtained from the Clinical Practice Research Datalink (CPRD), we conducted two matched case-control studies. Firstly, we examined the prevalence and risk of PCOS in women with autism and vice versa in a sample of 791 and 22263 women respectively, compared to age and GP practice matched controls. Frequency tables were calculated and differences tested using chi-square test for proportions. Secondly, we examined the risk of autism in first-born children of women with PCOS in a population of 8611 children with mothers with PCOS and matched controls. Cases and controls were linked to mothers using the CPRD Mother-Baby Link. Controls were matched on gender, GP practice, and year of birth (±2 years). The association between autism and maternal PCOS was modelled using conditional logistic regression, adjusting firstly for maternal age, marital status, and maternal psychiatric diagnoses, and secondly with additional adjustment for obesity, obstetric complications, and gestational diabetes. Autism diagnoses were based on previously validated Read code lists. PCOS was defined according to Read code PCOS diagnoses as well as by phenotypic parameters (a diagnosis of polycystic ovaries in addition to either ovulatory dysfunction or hyperandrogenism).
We found very strong evidence of increased rates of PCOS in women with autism (2.3% vs. 1.1%, p=0.006) and elevated rates of autism in women with PCOS (0.23% compared with 0.09%, p<0.001). The odds of having a child with autism for mothers with PCOS was also significantly increased, both in the unadjusted model and following adjustment for marital status, maternal psychiatric diagnoses, obstetric complications, and gestational diabetes (unadj. OR: 1.58, 95% CI: 1.27 – 1.98; adj. OR: 1.35, 95% CI: 1.06 – 1.71).
These two large-scale epidemiological studies provide strong evidence that women with PCOS and their children have a greater prevalence of autism. This may be of value in risk assessment. Prenatal and maternal sex-steroids may be a potential source of this association.