Women who suffer from polycystic ovary syndrome, or PCOS, are 59 percent more likely to give birth to a child with autism spectrum disorder than women without the disorder, according to a study published in the journal Molecular Psychiatry in December.
PCOS is a hormonal disorder that affects as many as 1 in 10 women and is the leading cause of infertility. The disorder, caused by cysts in the ovaries, is marked by abnormally high levels of the male hormone androgen, which can lead to acne, excessive hair growth, weight gain and ovulation problems. While all women produce androgens, women with PCOS overproduce them and this may account for the difference, according to the study's lead researcher.
"Women with PCOS have increased levels of androgens in their bodies compared to women without PCOS, even during pregnancy," Kyriaki Kosidou, a psychiatrist and researcher at Karolinska Institutet in Stockholm and lead author of the study, told The Huffington Post. Those androgens could subtly influence the fetus's developing brain and nervous system, Kosidou said.
The risk was even higher among women with PCOS who were also obese, perhaps because overweight women with PCOS tend to have even higher androgen levels than average-weight women with the disorder.
Although ASD is five times more common in boys than in girls, according to the National Institutes of Health, babies born to mothers with PCOS in the study had the same risk, regardless of the sex of the child.
The study examined all children born in Sweden between 1984 and 2007 and compared National Patient Register records of ASD to records of mothers with any lifetime recorded diagnosis of PCOS. Since women with PCOS are more likely to undergo fertility treatments than the average population, the study authors adjusted for the use of reproductive technology in their research.
It's important to keep in mind, however, that the study model only allowed for relative, not absolute, risk, meaning it compared the children of PCOS mothers to mothers without PCOS, both of whom bore children with ASD. In Sweden, the general population prevalence of ASD is only 1.5 percent, similar to the rates in the United States. In other words, a 59 percent increase sounds scary, but is still quite low.
Kosidou cautioned that the link between early life androgen exposure and ASD is still unclear and that women with PCOS shouldn't worry extensively about their children's health.
"While we did observe an increased risk for ASD, it was a modest increase for a relatively rare disorder," she said. "Chances are that children born to a mother with PCOS will not develop autism."
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