Fertility drugs and cancer
Fertility drugs, such as clomiphene citrate and various gonadotropins, are commonly used to help women conceive. There has been ongoing research into the potential association between the use of these drugs and an increased risk of certain cancers, particularly ovarian, breast, and uterine cancer. While some studies indicate a possible link between fertility drugs and ovarian cancer risk, it is important to recognize that factors like age, family history, and reproductive history also significantly contribute to ovarian cancer risk. For example, women at higher risk include those who have never given birth or have a family history of the disease.
The relationship between fertility drugs and cancer remains complex, as infertility itself may also elevate cancer risk, complicating clear conclusions. Additionally, hormone levels influenced by these medications may also play a role in cancer development. Although there is some evidence suggesting an association between clomiphene citrate and uterine cancer, further studies are necessary to establish definitive connections.
Overall, the conversation surrounding fertility drugs and cancer involves careful consideration of individual risk factors and the need for longitudinal studies to better understand the long-term implications of fertility treatment. Women considering fertility drugs are encouraged to consult healthcare professionals for personalized advice and monitoring, especially if they have a higher risk for cancer.
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Fertility drugs and cancer
DEFINITION: An association between the use of fertility drugs clomiphene citrate, follicle-stimulating hormone (FSH), human menopausal gonadotropin (MG), and gonadotropin-releasing hormone analog (GnRH), and ovarian cancer exists if there is a statistically significant increase in the risk of cancer during the lifetime of the user of fertility drugs. Although the major concern regarding fertility drugs and cancer since the 1990s has focused on ovarian cancer, some experts suggest a relationship between fertility drugs and cancers of the breast and uterus. Because fertility drugs evoke changes in hormone levels, the potential risk should be extended to any cancer that can be triggered or modulated by hormones, as well as any indirect effects on the offspring of the user of fertility drugs.
Fertility drugs and cancer: A woman’s risk of ovarian cancer is multifactorial. However, some factors increase the risk of ovarian cancer, while others decrease the risk. Ovarian cancer increases with age, family history of ovarian cancer, and in women who have never had a child. In contrast, the risk of ovarian cancer decreases in women who breastfeed, have at least one child, and use oral contraceptives. Ovarian cancer is related to the process of ovulation in most cases. Ovarian cancer follows an abnormal repair process on the surface of the ovary following the release of the egg during ovulation. Thus, increasing the number of ovulations (incessant ovulation), either by having no interruption of ovulation due to pregnancy or by inducing ovulation with fertility drugs, would theoretically increase the risk of ovarian cancer. Conversely, inhibiting ovulation vis-à-vis pregnancy or pregnancies, breast-feeding, or through the use of oral contraceptives would theoretically decrease the risk of ovarian cancer by reducing the lifetime number of ovulations.
Although some epidemiologic studies have shown an increased risk of ovarian cancer in women who have used fertility drugs, infertility itself, rather than fertility drugs, increases the risk of ovarian cancer. Because the peak onset of ovarian cancer occurs during the seventh decade of life, it is important to continue longitudinal studies to verify this finding. There is an association between using clomiphene citrate and uterine cancer. Because clomiphene citrate is chemically similar to tamoxifen (a drug routinely used to treat patients with breast cancer after surgery), which is associated with cancer of the uterus, further studies are needed.
Ovarian cancer: Approximately 20,000 women are diagnosed with ovarian cancer each year in the United States. The lifetime incidence of ovarian cancer for any given woman is approximately 1 in 87, excluding low malignant potential ovarian tumors. The lifetime risk of dying from ovarian cancer is 1 in 130. The symptoms of ovarian cancer in its early stages are minimal to none. In advanced cases, most women with ovarian cancer complain of abdominal pain, vaginal bleeding, abdominal bloating and distension, or a change in bowel habits.
There is no accepted screening protocol for ovarian cancer, unlike cervical cancer (which can be detected by a Pap smear) or breast cancer (which can be found by self-exam, a clinical breast exam, and mammography). The American College of Obstetricians and Gynecologists recommends all women have a manual pelvic examination during their well-woman examinations at intervals determined by their risk factors. The examiner palpates (feels) the ovaries during the manual pelvic examination. Although not recommended for women at low risk for ovarian cancer, for those at high risk, a blood test (cancer antigen 125, or CA 125) and a vaginal ultrasound in which the ovarian volume is determined may be beneficial.
The standard treatment for ovarian cancer is surgical, in the form of a total abdominal hysterectomy and removal of both ovaries with postoperative chemotherapy. The five-year survival rate for patients with ovarian cancer is 50 percent, depending on the stage at the time of diagnosis and the treatment rendered. The risk of ovarian cancer can be reduced by breastfeeding, using oral contraceptives, and undergoing tubal ligation, although the mechanism of protection for the latter is unclear. For women taking fertility drugs, when used as prescribed for less than twelve cycles with monitoring by a specially trained physician (reproductive endocrinologist), there are no convincing scientific studies that have shown an increased risk for ovarian cancer.
Bibliography
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