Diabetes drug may prevent or delay development of polycystic ovary syndrome, the most common cause of infertility in women

PCOS affects 7 to 10 percent of women of childbearing age and is the most common cause of infertility, affecting an estimated 5 to 6 million women in the United States, according to The Hormone Foundation.

"PCOS often presents in adolescence, with irregular menstrual cycles, acne, or too much body hair," said the study's senior author, Lourdes Ibáñez, MD, PhD, professor of pediatrics at the University of Barcelona in Spain and lead author of the study. "But we believe the critical years for PCOS development may be during childhood and puberty when excessive amounts of fat are stored. That excessive weight gain overexposes the ovaries to insulin, causing them to stop ovulating and start releasing male hormones, resulting in PCOS."

In this study of 38 girls with low birth-weight and early puberty, researchers compared the efficacy of early versus late metformin treatment to prevent adolescent PCOS. A group of 19 8-year-old girls were treated with daily doses of metformin for four years. A second group of 19 girls waited five years before they began receiving daily doses of metformin at age 13 and then continued treatment for only one year. They found that early metformin therapy prevented or delayed the development of hirsutism, androgen excess and PCOS more effectively than late metformin treatment.

"Metformin, when given across the potentially critical window of puberty, may have the capacity to reprogram metabolism toward less abdominal and liver fat," Ibáñez concluded. "In the years ahead, the focus of attention should shift from late treatment of PCOS and its complications, toward the early and large-scale prevention of PCOS, with measures such as diet, exercise and metformin in young girls."

Other researchers working on the study include: Abel Lopez-Bermejo of Dr. Josep Trueta Hospital and Girona Institute for Biomedical Research in Spain; Marta Diaz of the University of Barcelona in Spain; Maria Marcos of Hospital de Terrassa in Spain; and Francis de Zegher of the University of Leuven in Belgium.