Promising Infertility Drug Falls Short


metformin(Ivanhoe Newswire) -- A drug researchers hoped would boost birth rates among women with one of the most common causes of infertility fell short in a new study.

Metformin (Glucophage), which is used to treat diabetes, shown promise in earlier research involving women with polycystic ovary syndrome (PCOS) because it increased the frequency of ovulation. In the new study, however, increased ovulation did not lead to increased births.

In fact, women taking metformin had the lowest birth rates in the study, which compared the drug to the standard drug used to treat infertility in PCOS, clomiphene (Clomid). About a quarter of the women taking clomiphene ended up giving birth, compared to about 7 percent of those taking metformin. Combining the two treatments did not lead to better results, with about a quarter of women again having children.

"The results of this study underscore the need to test any new treatment rigorously, no matter how promising it may seem initially," reports Duane Alexander, M.D., from the National Institute of Child Health and Human Development, which funded the study.

Study investigator Richard S. Legro, M.D., from Pennsylvania State University College of Medicine in Hershey, agreed. "Our results show that you can't use ovulation as a surrogate for pregnancy. An ovulation on clomiphene treatment is twice as likely to result in pregnancy as an ovulation on metformin, thus all ovulations are not alike."

PCOS strikes about 7 percent to 8 percent of women in the United States, causing excess male hormones that interfere with ovulation and lead to enlarged ovaries. In addition to infertility, women affected by the condition face unwanted facial hair and acne, and are more likely to be obese.

SOURCE: The New England Journal of Medicine, 2007;356:551-566 via Ivanhoe Newswire