February 7, 2007
Contact: Kaylyn Kendall Dines
Phone: (973) 972-3000
National Study Shows Diabetes Drug
Ineffective in Combating Infertility Disorder
- Research is published in the Feb. 8th issue
of the New England Journal
of Medicine -
NEWARK — The findings of a National Institutes of Health study are published in the February 8 issue of the New England Journal of Medicine may be helpful for women who have an infertility disorder that is associated with a reproductive disorder called Polycystic Ovarian Syndrome.
Metformin, a medication that is used to treat diabetes and was believed to be helpful in overcoming the infertility disorder associated with PCOS, is relatively ineffective in helping women achieve pregnancy when compared with a standard treatment infertility drug called clomiphene.
Dr. Peter McGovern, associate professor and director of the Division of Reproductive, Endocrinology, and Infertility in the Department of Obstetrics, Gynecology and Women’s Health at the University of Medicine and Dentistry of New Jersey, was the only researcher in the tri-state area to participate in this nationwide study. Dr. McGovern was the lead investigator at the UMDNJ-New Jersey Medical School, which was one of twelve sites that participated in this study of 626 infertile women who were diagnosed with PCOS.
PCOS affects seven to eight percent of women and may be the most common cause of female infertility according to Dr. McGovern. With PCOS, an excess of male hormones interferes with ovulation. The ovaries become enlarged and filled with cysts. In addition to infertility, PCOS symptoms include irregular menstrual periods, excessive body and facial hair, acne and obesity.
“We believe women who want to conceive in spite of their Polycystic Ovarian Syndrome diagnosis may benefit from trying clomiphene treatments before trying metformin,” said Dr. McGovern. “In summary, our study supports the use of clomiphene citrate alone as the first-line therapy for infertility in women with PCOS.”
Women with PCOS frequently experience insulin resistance, a pre-diabetic condition in which higher-than-normal levels of insulin are required to allow glucose to enter tissues. Earlier studies had shown that drugs like metformin, which make the body more sensitive to insulin, could increase ovulation in PCOS patients. Several smaller studies had suggested that metformin, when taken alone or when combined with clomiphene, could result in increased fertility rates for PCOS patients when compared with clomiphene taken alone.
According to Dr. McGovern, at their respective sites each researcher randomly assigned women into one of three groups. The first group received clomiphene and a placebo, the second group received metformin and a placebo, and the third group received both metformin and clomiphene. The women took the treatments for up to six months. The researchers tested the women’s levels of the hormone progesterone to gauge ovulation.
The researchers found that fewer women in the metformin only group had given birth than had women in either of the clomiphene groups. In the metformin only group, 15 out of 208 women had given birth, or 7.2 percent. In the clomiphene only group, 47 out of 209 women had given birth, or 26.8 percent. The difference in the number of births between the clomiphene only group and the clomiphene-metformin group was not statistically significant.
The researchers also found that, compared with other women in the study, obese women were less likely to conceive during the course of the study and less likely to ovulate in response to metformin. Researchers noted that women in the combination therapy group ovulated more frequently than did the women in either the clomiphene-alone or the metformin-alone groups. However, the tendency to ovulate more frequently did not translate into a significantly greater number of pregnancies for the combination group.
Dr. McGovern said these findings were consistent with earlier studies that also reported an increase in ovulation from the combined therapy and that these early observations had led to researchers’ initial enthusiasm for metformin as a potential treatment for PCOS. He said, although the combination of the two drugs might stimulate more cycles of ovulation than clomiphene alone, these extra cycles might result in higher number of eggs that are not capable of fertilization or development.
The researchers also reported that women in the clomiphene groups had more occurrences of multiple pregnancies: 6.4 percent for the clomiphene only group, 3.3 percent for the combination group and 0 percent for the metformin group. Clomiphene is known to stimulate the release of more than one egg at a time. Dr. McGovern noted that the rate of multiple pregnancies identified in the study for women who were treated with clomiphene was less than the multiple pregnancy rate following in vitro fertilization - 33 percent.
The University of Medicine and Dentistry of New Jersey (UMDNJ) is the nation’s largest free-standing public health sciences university with more than 5,500 students attending the state's three medical schools, its only dental school, a graduate school of biomedical sciences, a school of health related professions, a school of nursing and a school of public health on five campuses. Annually, there are more than two million patient visits at UMDNJ facilities and faculty practices at campuses in Newark, New Brunswick/Piscataway, Scotch Plains, Camden and Stratford. UMDNJ operates University Hospital, a Level I Trauma Center in Newark, and University Behavioral HealthCare, a statewide mental health and addiction services network.