Protecting Your Fertility During Treatment
If you are premenopausal (still having menstrual periods), breast cancer treatments such as chemotherapy and hormonal therapy can affect your fertility. This may make it harder to become pregnant after treatment ends.
If you have just been diagnosed, it is important to discuss your fertility concerns with your healthcare team before starting breast cancer treatment. Your doctor may refer you to a fertility specialist, a doctor called a reproductive endocrinologist, who can help you learn more about the possible impact of treatment and ways to preserve your fertility. You may also find the Society for Assisted Reproductive Technology helpful.
Here are some methods that can help you protect your fertility after breast cancer treatment.
The best time to take eggs from your ovaries for future use is before treatment begins. For this process, fertility medicines are usually given for about 2 weeks to increase the number of eggs your body makes. Your doctor may give you tamoxifen, an aromatase inhibitor, or both during the egg-stimulating cycle, to lower possible exposure of your breasts to estrogen.
The eggs are removed during an outpatient surgery procedure. They may be frozen without being fertilized, or fertilized in a lab with sperm from your partner or a sperm donor. Then they are grown to form embryos. The eggs and embryos are frozen for use after breast cancer treatment. It is possible to have pre-implantation genetic testing to screen the embryos for chromosomal abnormalities or specific cancer risk gene mutations, if you have a known breast cancer gene mutation in your family. Your fertility specialist will have more information on these tests.
Egg or embryo freezing is the standard-of-care approach and most common method to preserve fertility. This process takes 2 to 6 weeks. Freezing your ovarian tissue or using medicines called GnRH agonists to suppress your ovaries are also possible, but both are considered experimental.
Fertility procedures often are coordinated with breast cancer treatment, usually during the weeks between surgery and chemotherapy. It can be stressful to make decisions about fertility right after a breast cancer diagnosis. You may want to get started with treatment quickly, or your doctors might recommend neoadjuvant therapy. Or maybe you haven’t thought about having future children, and cancer is now forcing you to do so.
Talk with your oncologist about timing—there may be ways to make a schedule work for you. Your oncologist can also communicate with the reproductive endocrinologist. This helps all your providers understand the timing for these procedures.
Some studies have shown that medicines called gonadotropin releasing hormone agonists (GnRH agonists) or luteinizing hormone-releasing agonists (LHRH agonists) may protect the ovaries from the harsh effects of chemotherapy so they can recover more fully and quickly. These medicines shut down, or suppress, your ovaries. They cause menopausal symptoms for as long as you take them. Shutting down your ovaries reduces the amount of estrogen your body makes.
The LHRH agonists are:
- goserelin (Zoladex)
- leuprolide (Lupron)
- triptorelin (Trelstar)
Ask your doctors to be specific about what kind of ovarian suppression they recommend. Some doctors use “ovarian suppression” or “ovarian ablation” to mean the same thing. Ovarian ablation can also mean surgery to permanently remove your ovaries.
Side effects may include
- bone thinning
- bone pain
- hot flashes
- joint and muscle aches
- loss of sexual interest
- mood changes
- vaginal dryness
- weight gain
LHRH agonists are still under study. Note that this approach does not take the place of standard methods of preserving your fertility, such as freezing eggs and embryos. Not enough research has compared whether LHRH agonists during chemotherapy results in higher fertility after chemotherapy compared to placebo treatment.