Endocrine Abstracts

Metformin has been used extensively in multiple reproductive settings including to ameliorate hyperandrogenism and chronic anovulation, to treat infertility, to prevent miscarriage and to prevent later pregnancy complications. Metformin does result in modest improvements in the PCOS phenotype with reductions in circulating insulin and testosterone levels, weight loss, and improved menstrual/ovulatory frequency. It is relatively ineffective as a solo agent to treat infertility, and further has a relative anti-fecundity compared to clomiphene alone, though it likely has a lower multiple pregnancy rate. Clomiphene remains the first choice for infertility therapy and the gold standard for women with PCOS. Metformin may have benefit as an adjuvant agent with clomiphene in select populations, such as obese women. Metformin may be useful to prevent OHSS when used in conjunction with gonadotropins. The benefit of metformin in IVF per se is uncertain. The use of metformin to prevent pregnancy loss or to prevent pregnancy complications is still experimental and better trials are needed to guide therapy. Current level of evidence recommends caution in the extended use of metformin during pregnancy. Metformin has been shown to delay the progression to diabetes in high risk female populations, such as those with IGT. It may also have some benefit for the treatment of premature pubarche. Metformin is ineffective as a weight loss agent in women with PCOS. Criteria for stopping Metformin (other then pregnancy or unacceptable side effects) are uncertain, and the long-term risk benefits are unknown in women with PCOS.

Declaration of interest

I fully declare a conflict of interest.