As a board certified Reproductive Endocrinologist and Infertility (REI) specialist at Reproductive Medicine Associates of Connecticut (RMACT), I am writing today to talk about the recent article published in the journal Molecular Psychiatry entitled: “Maternal polycystic ovary syndrome and the risk of autism spectrum disorders in the offspring: a population-based nationwide study in Sweden.” (Full citation can be found at the end of this post).
PCOS, (Polycystic Ovarian Syndrome) is a very common condition for our patients, and it typically includes irregular ovulation and periods. It is believed that 8-10% of all women have PCOS, and are therefore understandably concerned about the findings and implications of this study. It’s my intention to talk openly about the issues as I see them.
PCOS & Autism Study | The Findings
First, let’s summarize the article itself. In Sweden (and many Scandinavian countries), there are formal birth and healthcare registries that track health issues across the lifespan. This allows for good epidemiologic research that applies to those country’s populations, but are not necessarily generalize-able to different populations in different parts of the world that may have more complex, diverse and difficult populations to study.
The research group based in the department of public health sciences at the Karolinska Institute of Sweden queried the national healthcare database and conducted a matched case–control study nested within the total population of Sweden of children aged 4–17 who were born in Sweden from 1984 to 2007. They found 23,748 children who were diagnosed with an Autism Spectrum Disorder (ASD) and compared them to 208,796 control children who were never diagnosed with an ASD. In order to make all of the comparisons fair, they carefully matched the groups and stratified them by birth month and year, sex and region of birth in order to accurately compare apples to apples.
Once they accounted for all of these variables through complex statistical analyses, they found that maternal PCOS increased the odds of ASD in the diagnosed children by 59%, after adjustment for the confounding factors. This risk was further increased when maternal obesity was also present in the mothers in this study.
What Does This Mean For Women With PCOS?
I have to agree that on its face these findings are concerning for the 8-10% of women who have PCOS. However, I do not feel that these findings are set in stone, nor are they generalize-able to everyone. First and foremost, it is important to keep in mind that a 59% increase in a rare event is still in itself a rare event. Secondly, in the world of epidemiology a 59% increase is not a large one (even though it sounds huge) and statisticians generally do not become alarmed until there is a 2-3 times increase in their findings. That is when they sound a warning.
My biggest concern with this study, however, is that I am not sure if it is biologically plausible. The authors conclude that a hyper-androgenic state, that is slightly elevated testosterone levels that are sometimes, but not always, found in women with PCOS, are to blame for these findings. It is well known that the placenta has an enormous capacity for aromatization– which is turning androgens (the family of hormones that contain testosterone) into estrogens.
I am skeptical that there is as-yet-undiscovered mechanism in patients with PCOS that decreases the placenta’s stated job of aromatizing androgens– which is in place to protect all babies, not just those of patients with PCOS. The placenta is often referred to as an “androgen sink” meaning it washes out androgens so that very little, if any, testosterone can get through it to the baby. It is not impossible to think that there may be elevated testosterone levels in babies conceived by PCOS patients, but this is by no means a foregone conclusion in the world of reproductive medicine.
Second, not every patient with PCOS has elevated testosterone levels. It is one of the diagnostic criteria, but it is not required for the diagnosis of PCOS as long as the other criteria are met. So this study’s findings are not necessarily generalize-able for every patient with PCOS, particularly not the patients with normal testosterone levels.
Third, in medicine and science we do not make sweeping decisions and changes in thinking based on one study. Science requires proof of causation through randomized controlled trials that can be duplicated by other research groups in different patient populations rather than relying solely on observational, retrospective articles such as this one. I believe that this study is more of a beginning of the discussion on this subject, certainly not its end.
In summary, while I do think this one study is interesting, thought-provoking and well designed, it is not enough to change how we view and counsel huge populations of PCOS patients. I think that while this study opens the door for more investigation, it is not, by itself, a cause for alarm or dramatic change in the way we treat and counsel our many patients with PCOS.
Read the the recent article published in the journal Molecular Psychiatry entitled: “Maternal polycystic ovary syndrome and the risk of autism spectrum disorders in the offspring: a population-based nationwide study in Sweden.”