As more women delay childbearing to their late 30s and early 40s, many young breast cancer survivors are concerned about preserving their future fertility. If you are a premenopausal women recently diagnosed with breast cancer, here are answers to some questions you may have related to fertility following breast cancer treatment:
Will Chemotherapy Make Me Menopausal?
Systemic chemotherapy results in direct toxicity to the ovary and potentially premature menopause. The degree of damage to the ovaries will determine whether amenorrhea, or the absence of menstrual periods, is temporary or permanent and varies depending on the chemotherapy regimen given and your age when treated. Because certain chemotherapy regimens are known to affect ovarian function more than others, you should speak with your oncologist to weigh the risks and benefits of different treatment options.
If I Am Going to Need Chemotherapy,
Is There Anything I Can Do to Preserve Fertility Prior to Starting Treatment?
Cryopreservation of embryos, oocytes, or ovarian tissue, and ovarian suppression are options to preserve fertility prior to beginning treatment. Cryopreservation of embryos following in vitro fertilization has the highest likelihood of success. These options require expertise and advanced planning, so discussion with a reproductive endocrinologist should occur soon after a breast cancer diagnosis.
Can I Become Pregnant While on Tamoxifen?
No, tamoxifen can cause birth defects so it is important to have a reliable method of contraception while on this drug. Although it is recommended that patients with estrogen receptor-positive breast cancer take tamoxifen for at least 5 years, delaying childbearing increases the risk of menopause. The safety of interrupting tamoxifen treatment to conceive is controversial. A multi-institutional study, the “Pregnancy Outcome and Safety of Interrupting Therapy for Women With Endocrine Responsive Breast Cancer (POSITIVE)” trial, is currently investigating whether temporary interruption of endocrine therapy to permit pregnancy is associated with a higher risk of breast cancer recurrence. The study also aims to evaluate different specific indicators related to fertility, pregnancy, and breast cancer biology in young women. More information on this trial can be found at https://clinicaltrials.gov.
How Successful Are Women at Becoming Pregnant After Breast Cancer?
It is estimated that 5% to 15% of young breast cancer survivors will become pregnant at least once after their diagnosis. There is no evidence to suggest an increased risk of birth defects in the offspring of breast cancer survivors. However, women who become pregnant after receiving cytotoxic chemotherapeutic agents may be at increased risk of complications during pregnancy or just after delivery, so they should seek high-risk obstetric care.
How Long Should I Delay Pregnancy After Being Treated for Breast Cancer?
While there are no data to suggest that pregnancy worsens prognosis or increases chance of recurrence, it is generally recommended that breast cancer survivors wait at least 2 years before becoming pregnant so that they are beyond the period of the highest risk of recurrence. A discussion with your medical oncologist is important to determine if this is an option for you.