Newswise — For premenopausal women, the decision of whether to undergo a hysterectomy —removal of the uterus — is a challenging one. To make things more complex, added pressure to decide whether to remove the ovaries can arise — a decision that researchers say relies more on the preferences of the woman or her surgeon than on evidence-based medicine. Prophylactic oophorectomy is the medical term for removal of healthy ovaries to prevent the potential risk of developing ovarian cancer later in life.
"Prophylactic oophorectomy is performed across the world on the basis of very limited evidence," said lead review author Leonardo Orozco, M.D., an attending OB/GYN at Women's Hospital San JosÃ© in Costa Rica. "Questioning this practice is a crucial step in advancing our ability to make decisions that may ultimately improve the health and well-being of women."
However, of the 119 studies that the researchers identified, only one controlled clinical trial met the review's inclusion criteria — and it was not particularly strong.
"After our search, we were able to find only one clinical control trial of low-quality that has been used to justify such a high number of prophylactic oophorectomies every year," Orozco said.
That single study included 362 women, who were ages 45 to 55 years when it began. Of those, 217 underwent hysterectomy alone and 106 underwent hysterectomy plus oophorectomy. The study looked at the average changes in psychological well-being and sexuality, both before and one year following the surgery.
Despite the study's limitations, Orozco says the review's results are worth noting. "For me, the most important result of this research was to raise the awareness that, as physicians, we must always question why we are performing a specific procedure. We cannot always rely on training, as there are 'habitual' procedures that we undertake, which may not be the best evidence-based decision."
The review appears in the latest issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews like this one draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
"This is an almost impossible area to research insofar as a prospective, randomized, double-blind controlled trial is totally impossible," said Mary Jane Minkin, M.D., a clinical professor of OB/GYN at Yale University School of Medicine. Therefore, she said, "This is one area where individualization of care is absolutely necessary."
In the context of few studies to justify a choice either way, Minkin says she tells her patients "that it is their decision, as long as the ovaries are healthy."
"But," she adds, "it takes a lot of informed consent to help them make this decision and many docs do not take the time to go through this lengthy decision-making process." With patients going from one HMO to another, doctors do not really get a chance to know these women really well, "and it becomes that much more difficult to make an informed decision," she says.
The study analyzed in the review included premenopausal women who underwent hysterectomy for benign gynecological conditions. The reviewers excluded all studies where the women had gynecological cancer, were postmenopausal, or both — as defined by the original study authors.
Both Orozco and Minkin acknowledge that myriad factors go into the decision to remove the ovaries. For example, "We know that women who undergo early menopause, either medically, or particularly surgically [after removal of the ovaries], are at very high risk for cardiovascular disease and osteoporosis," Minkin says. "If they are not given estrogen therapy, estimates in some papers are as high as a seven-fold risk of cardiovascular disease. There is a reduction in risk of breast cancer, to be sure, but the other diseases are substantially increased."
Orozco adds that it is important to consider the long-term implications of ovary removal — some of which remain unclear. For example, even after menopause, the ovaries produce significant amounts of certain hormones that other tissues convert to estrogen. "Therefore," he says, "there could be underlying advantages of ovarian function "¦ that may mean that removal of the ovaries has clinically significant consequences."
"The conclusions of this review are limited by the lack of data," Orozco says. "However, it demonstrated that more research of higher methodological quality is needed in order to justify an intervention that we still don't know is beneficial or harmful."
Orozco LJ, et al. Hysterectomy versus hysterectomy plus oophorectomy for premenopausal women. The Cochrane Database of Systematic Reviews 2008, Issue 3.
The Cochrane Collaboration is an international nonprofit, independent organization that produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions. Visit http://www.cochrane.org for more information.