Is PCOS related to epilepsy?
The percentage of women reported to have PCOS varies widely because different researchers have used different definitions of the syndrome and have studied different groups. Estimates range from as low as 3-4% to as high as 18-19% of all women.
Studies of women with epilepsy have suggested that PCOS occurs in 13% to 25%, depending on the definition used and on characteristics such as the type of epilepsy and the kinds of seizure medicines used by the women studied. It does appear that PCOS occurs significantly more often in women with epilepsy than in others, especially among certain groups. Studies using much larger groups will be needed for doctors to find out the details of how PCOS is related to the many types of epilepsy and seizure medicines.
One explanation for the connection between PCOS and epilepsy is that women whose seizures begin in the left temporal lobe may be more likely to have certain hormonal abnormalities that prevent the follicles in the ovary from maturing. This leads to anovulation, the collection of cysts, and the release of more male hormones—all the criteria for a diagnosis of PCOS.
PCOS has another link to epilepsy: it may increase or worsen seizures. The hormonal abnormalities related to anovulation include a lack of progesterone, which the ovaries usually produce in the days after ovulation. Progesterone has antiseizure and mood-stabilizing properties. The ovaries of women with PCOS, on the other hand, continue to produce estrogen, which promotes seizures and anxiety.
Is PCOS related to seizure medicines?
Some (but not all) studies of women with epilepsy have found that PCOS is more common in those who have been taking Depakote (valproate) than in those taking some other seizure medicines. Teenagers who take Depakote may be at the highest risk.
A possible explanation for the effect of Depakote is that it is one of the few seizure medicines that are not "enzyme-inducing." Enzyme-inducing medications promote the liver's production of substances that lower blood levels of the male hormones involved in PCOS. In effect, enzyme-inducing seizure medicines like Tegretol/Carbatrol (carbamazepine) or Dilantin/Phenytek (phenytoin) treat PCOS but Depakote does not. Lamictal (lamotrigine) is another seizure medicine that has been found to reverse the features of PCOS.
Depakote also promotes weight gain, which is associated with higher levels of insulin and of active male hormones, both factors linked to PCOS.