Safety of fertility drugs
Safety of fertility drugs: is it cause for concern?
For millions of women struggling to conceive, fertility drugs are the first step
in treatment. Clomiphene works by stimulating hormones in the brain that activate an egg (or eggs) to develop and be released from the ovaries. Gonadotropins stimulate the ovaries directly to produce eggs. Women usually produce only one or two eggs a month. Human menopausal gonadotropin (hMG), urofollitropin, or recombinant FSH causes the ovaries to produce multiple eggs. One of these drugs is injected into the muscle or under the skin.
What are the risks of gonadotropin treatment?
• Conceiving multiples is the most common complication of gonadotropin treatment. Of these pregnancies, two-thirds are twins and one-third are triplets.
• Although many couples consider this a blessing, carrying multiples increases the risk of miscarriage and other complications.
• During stimulation for natural conception or IUI, if three or more follicles are growing to maturity or if blood estrogen exceeds a certain point, patients are asked to stop injections to prevent a condition called hyperstimulation.
• Women who take a gonadotropin occasionally develop ovarian hyperstimulation syndrome (OHSS). OHSS occurs when a woman produces too many eggs after taking the medicine. The ovaries swell rapidly, and fluid collects in the abdomen or around the heart or lungs. About 10 to 20 percent of gonadotropin cycles result in a mild form of OHSS, which can cause sudden weight gain, nausea, vomiting, or diarrhea, but usually goes away on its own. In 1 to 2 percent of gonadotropin cycles, OHSS is severe enough to require hospitalization and can lead to blood clots, kidney problems, or very rarely, death.
• Women may notice breast tenderness, a rash or swelling at the injection site, a swollen abdomen, or mood changes during fertility treatment.
Fertility treatment and cancer.
During IVF treatment, medications are administered to stimulate the reproductive systems. As a result, women are exposed to high levels of estrogen, which the National Institute of Environmental Health Sciences lists as a known carcinogen. But based on current research, scientists say there is little cause for concern.
As for infertility due to ovarian cancer, it is associated with an increased risk. Compared to the general population, infertile women have a higher incidence of ovarian cancer, but not one caused by IVF. The drugs have recently been linked to a very small increased risk of non-invasive ovarian tumors. But experts don’t think the dangers are significant enough to warrant additional screening for women who have taken fertility drugs in the past.
Fertility drugs do not increase the risk of breast cancer, although they can speed up the growth of pre-existing breast cancer. Therefore, before starting IVF treatment, it is mandatory to check for breast diseases.
Fertility treatments raise hormone levels for a few days, much shorter than the highest hormone exposure in nine months of pregnancy. Therefore, the risks of developing cancer are not a concern.