by Elyce Cardonick, MD
For many cancer survivors – both men and women alike – starting, expanding, or completing one’s family after cancer is a significant desire. But for female cancer survivors, many want to know, “Is pregnancy safe after cancer?” This is of particular concern for breast cancer survivors who may worry about the elevated estrogen levels that occur during pregnancy.
The good news is, for almost all cancer survivors (choriocarcinoma aside), pregnancy does not affect the risk of recurrence of any type of cancer – even breast cancer. This is true even for women with prior estrogen-positive cancers. In fact, some studies suggest that women with a history of early-stage breast cancer who become pregnant after completing treatment actually see an improvement in survival overall.
There is no optimal time to conceive after completing cancer treatment. Timing of pregnancy depends in part on factors that are specific to each individual; for example, the type of treatment you had, your tumor type, and your prognosis. In general, though, as the highest risk for cancer recurrence is in the first two years after completing treatment, most experts suggest that female cancer survivors wait two years after finishing treatment before trying to get pregnant. It’s also wise to see your healthcare provider for a thorough evaluation to confirm cancer remission or cure before attempting conception. All that said, however, this doesn’t mean that a pregnancy that occurs spontaneously within the first two years after completing cancer treatment will increase your risk of cancer recurrence. The two-year wait period is meant as a precaution to lessen the likelihood that a cancer recurrence and a pregnancy will happen at the same time; it does not affect your overall risk of recurrence.
Most experts suggest that female cancer survivors wait two years after finishing treatment before trying to get pregnant.
For ER-positive breast cancer survivors, there is one additional factor to consider when it comes to pregnancy timing. The difficulty for these women is knowing when to electively stop taking tamoxifen, as this drug should not be taken during pregnancy or while you are trying to get pregnant. If you cannot commit to completing the full five to ten years that is recommended for people with ER-positive breast cancer, you should talk with your oncologist to decide together a minimum number of years to stay on tamoxifen before planning a pregnancy. In most cases, trastuzumab, or Herceptin, may be continued up until the time of conception but then would need to be stopped at the first sign of pregnancy, as this drug should not be taken during pregnancy either.
Studies of children born to female cancer survivors who were treated for childhood cancer with chemotherapy, radiation therapy, or both, have shown that these babies have no increased risk of birth defects, single gene disorders, or chromosomal genetic syndromes. However, studies have shown that adolescent and young adult cancer survivors may be at increased risk for preterm delivery, as well as having babies with low birth weight. And some female cancer survivors may have an increased risk of developing conditions like gestational diabetes, anemia, and pregnancy-induced high blood pressure, as well as of having a cesarean delivery.
Overall, however, most cancer survivors go on to have healthy pregnancies and babies. So, if you are thinking about becoming pregnant after cancer treatment, talk to your healthcare provider. If cancer hasn’t affected your fertility, your doctor can work with you to ensure you are in the best health possible prior to planning a pregnancy. And then you can look forward to what should be a safe, healthy pregnancy.
Dr. Elyce Cardonick is a professor of obstetrics and gynecology, a maternal-fetal medicine specialist, and director of the Pregnancy and Cancer Registry at Cooper University Health Care in Camden, NJ. Since 1997, she has maintained an international database for pregnant women with cancer – the Cancer and Childbirth Registry – which follows women through diagnosis, treatment, and delivery, and conducts annual assessments of their children. She is also on the advisory board of Hope for Two … The Pregnant with Cancer Network.
This article was published in Coping® with Cancer magazine, January/February 2018.