When women are included in trials at all, they tend to be tested in the early follicular phase of their menstrual cycle, when hormone levels are at their lowest – i.e. when they are superficially most like men. The idea is to ‘minimise the possible impacts oestradiol and progesterone may have on the study outcomes’. But real life isn’t a study and in real life those pesky hormones will be having an impact on outcomes. So far, menstrual-cycle impacts have been found for antipsychotics, antihistamines and antibiotic treatments as well as heart medication. Some antidepressants have been found to affect women differently at different times of their cycle, meaning that dosage may be too high at some points and too low at others. Women are also more likely to experience drug-induced heart-rhythm abnormalities and the risk is highest during the first half of a woman’s cycle. This can, of course, be fatal. (IW, pp.204-5)

In comparison to participants without PCOS, participants with PCOS were almost four times more likely to have pre-diabetic conditions and three times more likely to have Type 2 diabetes. In people with diabetes, chronic elevations in glucose may damage blood vessels in the heart.

The prevalence of high blood pressure and high cholesterol were 1.7 times higher for participants with PCOS than participants without PCOS. High blood pressure is when blood flows with too much force, and this can damage the walls of arteries over time. Too much bad cholesterol can clog or block arteries, preventing the flow of blood.

A majority, 61%, of participants with PCOS reported obesity, defined by a Body Mass Index (BMI) of more than 30 kg/m2. Prevalence of obesity was almost double for participants with PCOS than participants without PCOS. Obesity can impact cholesterol levels, affect blood pressure, and increase risk of conditions like diabetes.

Irregular heartbeat, or arrhythmia, was more common among participants with PCOS (5.6%) than participants without PCOS (3.7%). Of the participants that did not report a PCOS diagnosis but reported family history of PCOS, 6.2% had arrhythmia.