Our success in fertility treatment is secondary to the ability to generate embryos. The generation of embryos is a result of our ability to stimulate the ovaries to produce more than one oocyte (which is what is achieved each menstrual cycle). The dominant follicle is the most responsive of the 200 or so candidate oocytes that are present monthly. Other follicles with almost equivalent sensitivities to stimulatory medications also grow. Our ability to select multiple follicles for growth is secondary to alterations in endogenous hormones and the addition of injectable hormones (FSH and LH). It is the reason for success and the source of concern as to whether continued exposure to these hormones places women at risk for certain cancers. However, it has been found fertility medications do not increase the risk of invasive ovarian cancer.
Although some clinic studies have suggested a link between such fertility drugs and the risk of cancer, these studies and their results are often difficult to interpret. Data is difficult to interpret because the incidence of cancers are generally low in the population undergoing ART (assisted reproductive technologies) and often cancers are detected many years after treatments have been completed.
Women who are at risk for invasive ovarian cancers are the same subset of women who present for fertility services – women who haven’t had a pregnancy and with infertility. The majority of studies from 1990s forward have failed to demonstrate clear, causal relationships of exposure and risk of cancer. There is reasonable data to the contrary. There is no meaningful risk of invasive ovarian cancers following the use of fertility medications in women who have infertility. Because of the commonality of ART and fertility medications; it is imperative to continue to monitor risk assessment for the common good health.
The science of ART and IVF has progressed in both our ability to generate and to cultivate embryos. The result is faster times to pregnancy; often the result of skipping the prodrome of multiple stimulatory cycles of timed intercourse and intrauterine inseminations. The science progresses toward mindful IVF with the transfer of single embryos promoting the health of mother and fetus alike.