Many women have trouble getting pregnant due to irregular periods. One of the most common reasons for having irregular menstrual cycles is polycystic ovary syndrome (PCOS). The typical symptoms of PCOS are unpredictable periods and evidence of high male hormone levels (such as excess hair growth on the face or body). Two other common features of PCOS are excess body weight and insulin resistance.

It is because of this insulin resistance that many women with PCOS are prescribed metformin. Metformin (Glucophage) is an insulin-sensitizing medication that is widely used in treating type 2 diabetes. Women with PCOS do not necessarily have type 2 diabetes, (although they have a higher lifetime risk of developing it), but their bodies may respond in a manner similar to someone who does have diabetes. Therefore, metformin has been extensively studied in women with PCOS.

Women with PCOS are often given fertility medications to help them ovulate. These medications can come in the form of oral pills, such as clomid or letrozole, or in the form of shots, such as gonadotropin injections. Metformin can be used in addition to any of these medications. It is not uncommon for women with PCOS to be on a combination of metformin and ovulation induction medications in order to achieve a pregnancy. Metformin is a category B medication that has been shown to be safe in pregnancy and is usually continued into the first trimester.

Women with PCOS may need to do in vitro fertilization (IVF) to become pregnant. One of the risks of IVF is ovarian hyperstimulation syndrome (OHSS). PCOS patients are at a higher risk for developing OHSS because they tend to be young with many follicles. Last month, a randomized controlled trial was published in the Fertility and Sterility journal which showed that metformin reduces the risk of OHSS in patients with PCOS undergoing IVF.

One hundred twenty patients were studied in which 60 women were placed on metformin and 60 women were given placebo pills. The group of women on metformin had a significantly lower rate of OHSS. There was no difference in embryo quality or pregnancy rates between the two groups.

If you have irregular periods or have been diagnosed with PCOS, consider asking your physician if metformin may be a good medication for you to try.