Infertile couples often turn to fertility drugs and insemination in hopes of becoming pregnant. Now, the first solid data on success rates of several common infertility treatments is available to help them decide what to do.
Results of the first large-scale, controlled clinical trial of these treatments, led by David S. Guzick, M.D., Ph.D., chair of the Department of Obstetrics and Gynecology at the University of Rochester Medical Center, will be published in the January 22 New England Journal of Medicine. The study determined that a combination of fertility drugs and insemination was the most effective, with a 33 percent pregnancy rate.
“Demand for effective infertility therapy has often led to practices that become accepted without the benefit of data from randomized, controlled clinical trials,” Guzick said. “These data will provide couples with realistic expectations as they consider their options for achieving pregnancy.”
Two of the most common treatments are superovulation, in which the ovaries are stimulated with hormones known as gonadotropins to promote ovulation; and intrauterine insemination, where active sperm are injected into the uterus. “Among infertile couples, the combination of superovulation and intrauterine insemination was associated with a three-fold higher likelihood of pregnancy than no treatment, and a two-fold higher likelihood than either superovulation alone or intrauterine insemination alone,” Guzick reported.
The study was funded by the National Institutes of Health and involved 932 couples in 10 clinical sites. It is the first large-scale study to include a no-treatment comparison. Couples underwent a series of tests and met certain criteria to qualify as infertile. All women in the study were determined to have “unexplained” infertility, indicating that tests could not identify a specific cause of infertility. Couples were then assigned to one of four treatment groups, including intrauterine insemination with superovulation, intrauterine insemination alone, superovulation alone and no treatment. They were studied through four treatment cycles unless pregnancy occurred.
Compared with infertile couples who did not use fertility methods, couples in the superovulation and intrauterine insemination group had a 33 percent pregnancy rate. The pregnancy rate was 19 percent for the superovulation group and 18 percent for the intrauterine insemination group. The control group, which used no treatment, had a 10 percent pregnancy rate.
“Until now, efficacy for these common treatments – as for many medical treatments – was suggestive, not firm,” Guzick noted. “For infertile couples, these very common treatments, though expensive and with some side effects, are now shown to be effective. Patients receiving them can be reassured and have an estimate of their efficacy on which to base their decisions for treatment.
“These results must be considered along with current pregnancy rates from in vitro fertilization, the costs of various procedures, and other factors such as the woman’s age and the potential for multiple pregnancies.” In 1997, the In Vitro Fertilization Program at Strong Memorial Hospital achieved 46 percent pregnancy rate, up from 42 percent the previous year.
Of the 186 pregnancies achieved in this study of fertility drugs and insemination, 24 were multiple pregnancies, including three sets of quadruplets, four sets of triplets and 17 pairs of twins.
“We recommend that couples be informed of all their options, be provided with realistic information about the chances of success as well as costs and complications, and be involved in the final decision,” Guzick concluded.