A study carried out at the University of Birmingham has found that contraceptive pills may offer more than just their primary role as birth control. It was found that for people with polycystic ovary syndrome (PCOS), the pill reduced their chance of diabetes by a quarter.

Around 10 percent of women suffer from PCOS, and it is associated with a higher risk of a number of diseases, including becoming twice as likely to develop type 2 diabetes.

PCOS is caused by irregular levels of androgens in the blood, the hormones that contribute to reproduction found in all sexes. Due to these higher levels, symptoms include fertility issues, unwanted hair growth, acne, and more. Weight gain is another common feature that makes the body less receptive to insulin, triggering the onset of diabetes and the release of more androgens.

In a case study of 4814 women, it was found that the risk of developing diabetes was reduced by 26 percent if taking the contraceptive pill. First author Dr. Michael O’Reilly gave an explanation to the University of Birmingham as to why this may be: “The pill contains estrogens which increase a protein in the blood called sex hormone-binding globin (SHBG). SHBG binds androgens and, thereby, renders them inactive. Thus, if the pill is taken, SHBG increases”. In short, the pill decreases the amount of androgens in the blood and therefore decreases the risk of diabetes.

This study, published in Diabetes Care, is the largest in the world to date investigating the link between PCOS and diabetes risk. Future steps would be to apply this potentially vital information to a wider range of populations around the world. This way we can see if the link is found globally by removing bias from Northern Europe.

Source study: Diabetes Journal – Polycystic Ovary Syndrome, Combined Oral Contraceptives, and the Risk of Dysglycemia: A Population-Based Cohort Study With a Nested Pharmacoepidemiological Case-Control Study