Autism spectrum
disorder (ASD), a very emotionally charged and controversial issue, has spurred
numerous studies investigating potential genetic and environmental etiologic factors.
One popular hypothesis is that prenatal
androgen (e.g. testosterone) exposure may modify brain development and contribute
to the development of ASD.
The basis for
this hypothesis comes from the fact that polycystic ovary syndrome (PCOS), an endocrine disorder affecting
~ 5–15% of women, is characterized by ovarian dysfunction, increased androgen
production, and metabolic disturbances such as obesity and insulin resistance. Women with PCOS manifest increased circulating
levels of androgens as well as hyperinsulinemia during pregnancy. This has been associated with abnormal placental
steroid production and increased testosterone in amniotic fluid.
Along these lines, a
recently published study from Sweden (see below) postulates a link between maternal PCOS and an increased risk of autism in their children. In the study, 24,000 children with autism were
compared with 200,000 without the disorder from a health and population
register database. The study found that children born to mothers with PCOS had
a 59% greater risk of autism development - a risk that further increased if the
mother was also obese.
So where does this
research leave us? Like many other
preliminary studies, it requires confirmation. And remember that "association" does not mean "causation". Nevertheless, the study should prompt further investigation into the potential role of sex
steroids in the etiology of ASD.
Judith Wolf, MD
Associate Director, WHEP
*****************************************************************************
Kosidou K, Dalman D,
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. Molecular Psychiatry (2015), 1–8. http://www.nature.com/mp/journal/vaop/ncurrent/pdf/mp2015183a.pdf
