Many women diagnosed with breast cancer, especially younger women, are concerned about their ability to have children after treatment. Some breast cancer treatments can cause temporary infertility or make it harder to get pregnant after treatment ends. Other treatments, especially certain chemotherapy regimens, can cause early menopause and infertility.
A meta-analysis suggests that women diagnosed with early-stage breast cancer who are treated with gonadotropin-releasing hormone agonists in addition to chemotherapy may be more likely to have their periods return after treatment ends.
The study was published online on Oct. 1, 2015 by JAMA Oncology. Read the abstract of “Gonadotropin-Releasing Hormone Agonists for Ovarian Function Preservation in Premenopausal Women Undergoing Chemotherapy for Early-Stage Breast Cancer: A Systemic Review and Meta-analysis.”
Gonadotropin-releasing hormone agonists are medicines that lower the amount of sex hormones in the body. In women, they stop the ovaries from making estrogen and progesterone. In men, they stop the testicles from making testosterone. Gonadotropin-releasing hormone agonists are also called GnRH agonists, GnRHa, luteinizing hormone-releasing hormone agonists, LH-RH agonists, and LHRHa. Lupron (chemical name: leuprolide), Trelstar (chemical name: triptorelin), and Zoladex (chemical name: goserelin) are all luteinizing hormone-releasing hormone agonists.
A meta-analysis is a study that combines and analyzes the results of many earlier studies. In this case, the results from 856 women from seven studies conducted between 1975 and 2015 were analyzed. All the women were premenopausal when diagnosed with early-stage breast cancer. All the women were treated with chemotherapy. Half of the women also were treated with a gonadotropin-releasing hormone agonist.
To figure out whether the women’s ovaries started functioning after treatment, the researcher looked to see how many women had regular periods return 6 months or 12 months after chemotherapy was completed.
The researchers found that women treated with a gonadotropin-releasing hormone agonist in addition to chemotherapy were more likely to have regular periods start again after chemotherapy ended compared to women treated with chemotherapy alone:
- 6 months after chemotherapy ended, women treated with a gonadotropin-releasing hormone were 2.41 times more likely to have regular periods return
- 12 months after chemotherapy ended, women treated with a gonadotropin-releasing hormone were 1.85 times more likely to have regular periods return
The researchers also said their analysis suggested that women who were treated with chemotherapy and a gonadotropin-releasing hormone were more likely to become pregnant after treatment was completed, but these results weren’t reported the same way in all the studies and pregnancy wasn’t the main outcome in any of the studies. The researchers concluded that there wasn’t enough evidence to decide if adding gonadotropin-releasing hormone agonists to chemotherapy to treat early-stage breast cancer helped preserve fertility.
The results of this study seem encouraging and echo the results of another study on adding luteinizing hormone-releasing hormone agonists to chemotherapy to preserve ovarian function that was published at about the same time.
If you’re a premenopausal woman who’s been diagnosed with breast cancer and are concerned about preserving your fertility, you might want to talk to your doctor about this study. It may be possible that you can be given a gonadotropin-releasing hormone agonist in addition to chemotherapy to shut down your ovaries and possibly help preserve your fertility.
There also are other options available, including harvesting mature eggs from your ovaries before treatment starts. The most important thing to do is to talk to your doctor about fertility as you’re planning your treatment. You also can ask for a referral to a fertility specialist for counseling before treatment begins.
For more information, visit the Breastcancer.org pages on Fertility and Pregnancy Issues During and After Breast Cancer.