Authors: Courtney Johnson
A population-based, matched case–control study conducted at the Karolinska Institutet (Stockholm, Sweden) has determined a potential causal association between maternal polycystic ovarian syndrome (PCOS) and an increased risk of development of autism spectrum disorders (ASDs) in their offspring. . The findings, which were published recently in Molecular Psychiatry, point to increased prenatal exposure of the child to androgen hormones in mothers with PCOS as a potential mechanism for the relationship.
ASDs represent a wide range of neurodevelopmental disorders, involving a complex interplay between genetics and the environment and being characterized by impaired language and social interaction. However, there is as of yet a limited understanding of the underlying causes and etiology of ASDs.
PCOS is one of the most common endocrine disorders, affecting 5–15% of women of child-bearing age. It is associated with the increased production of androgens, which are involved in the development of the brain and CNS as well as the generation of male-type characteristics.
The current study utilized nationwide health registry databases in Sweden to generate an anonymized dataset, examining all children aged 4–17 years of age, who were born between 1984 and 2007. Researchers identified 23,748 cases of ASD and compared them to 208,796 controls matched by birth month, birth region, birth year and sex.
“We found that a maternal diagnosis of PCOS increased the risk of ASD in the offspring by 59%,” stated Kyriaki Kosidou (Karolinska Institutet). “The risk was further increased among mothers with both PCOS and obesity, a condition common to PCOS that is related to more severely increased androgens.”
Although ASDs are four-times more common in males than females, the current study observed no risk difference between the sexes of the study cohort.
While increased exposure to androgens is a potential explanation for the observed association, the mechanisms driving the relationship between maternal PCOS and ASD in offspring were not investigated in the current study. In addition to the increased level of androgens, the authors therefore postulate that another possible explanation for the linkage could be due to shared genetic influences between PCOS and ASDs or other metabolic problems common to PCOS.
“It is too early to make specific recommendations to clinicians in terms of care for pregnant women with PCOS, though increased awareness of this relationship might facilitate earlier detection of ASD in children whose mothers have been diagnosed with PCOS,” commented Renee Gardner (Karolinska Institutet).
Although awaiting further analyses to confirm its findings, the current study has the potential to direct additional investigation into the underlying mechanisms of ASDs by indicating hitherto unexplored areas of research into the etiology of ASDs.
Sources: Karolinska Institutet press release; Kosidou K, Dalman C, Widman L et al. Maternal polycystic ovary syndrome and the risk of autism spectrum disorders in the offspring: a population-based nationwide study in Sweden. Mol. Psychiatry doi:10.1038/MP.2015.183 (2015) (Epub ahead of print).