no increased cancer risk from fertility meds?
A new study suggests that there is no significant increased risk of developing ovarian cancer from drugs used to stimulate the ovaries in fertility treatment.
There has been much debate and controversy as to whether short or long term exposure to ovarian stimulation drugs could have adverse health effects. The biggest long term concern is ovarian cancer, a particularly deadly form since it is difficult to detect.
Although many infertiles and singles may opt not to think too hard about the risk of developing ovarian cancer in the quest for a baby — given the potential outcome of treatment — it is still a common concern causing anxiety in many. While health risks are disclosed in the fine print of any package of medicine, many doctors (especially REs) tend to dismiss these risks as minimal or insignificant. Besides, for most, the potential benefit of a real baby far outweighs some abstract, unproven, long term health risk, in terms of likelihood and immediacy.
Still, few long term studies have resolved the ongoing controversy. Previous studies suggesting an increased risk for ovarian cancer were limited by small samples and may have been too short to adequately assess long term risk. In addition, because infertility is a risk factor for ovarian cancer, it is difficult to determine whether increased risk is attributable to infertility itself or drugs used in fertility treatment. It is also difficult to control for potentially confounding factors such as oral contraceptives.
Recently published in the British Medical Journal [abstract, editorial, full article], the new study covered over 54,362 women undergoing treatment at all Denmark fertility clinics between 1963 and 1998. Four sets of drugs were evaluated (gonadotrophins, hCG, gonadotrophin releasing hormones, and clomid). The median age at referral was 30, and the median age at follow-up was 47.
While further long-term study is needed to track participants as they continue to age, researchers found no compelling increased risk even for women undergoing multiple treatments. Apparently researchers did find a significant increased risk for a common yet serious type of ovarian cancer among women who used clomid, but they suggest this may be attributable to chance.
Will these findings relieve the anxiety that many women (and men) have about the long term effects of treatment? According to the editorial, “These data are reassuring and provide further evidence that fertility drugs do not increase a woman’s risk of ovarian cancer to any great extent, although small increases in risk cannot be ruled out.”