Pregnancy After Breast Cancer

Breast cancer is most common in older women. But if you are a younger woman who has had breast cancer, you might question if this has affected your fertility (ability to have children) and if there are any extra risks if you become pregnant.

Many women are able to become pregnant after being treated for breast cancer. However, some treatments can make it harder to get pregnant. If you think you might want to have children one day, or just want to keep your options open, the best time to talk to your doctor about this is before you begin breast cancer treatment.

Can I have a baby after having breast cancer?

Some treatments for breast cancer might affect a woman’s fertility. For example, chemotherapy for breast cancer might damage the ovaries, which can sometimes cause immediate or delayed infertility. Still, many women are able to become pregnant after treatment. For more about how cancer treatment can affect fertility, see Female Fertility and Cancer.

Could pregnancy or breastfeeding make my breast cancer come back?

Many breast cancers are sensitive to estrogen, so there has been concern that for women who have had breast cancer, the high hormone levels that result from a pregnancy might increase the chance of the cancer coming back. However, studies have not shown that pregnancy increases the risk of the cancer coming back after successful treatment.

Some women might not be able to breastfeed after breast cancer treatment, depending on the treatment they received and other factors (see below). But for those who are able to, breastfeeding after treatment is not thought to increase the risk of breast cancer recurrence. Breastfeeding (especially for a year or more) is linked to a lower risk of developing breast cancer, although there is less research about whether it can help  lower the risk of breast cancer coming back after treatment.

How long after breast cancer treatment should I wait before becoming pregnant?

Breast cancer survivors who want to become pregnant are sometimes advised to wait at least 2 years after treatment is finished before trying. The best length of time to wait is not clear, but 2 years is thought to be enough time to find any early return of the cancer, which could affect your decision to become pregnant.

For women with hormone receptor-positive breast cancer, adjuvant hormone therapy is typically recommended for 5 to 10 years after the initial treatment. Women who want to have children during this time are often advised to take hormone therapy for at least 2 years before stopping it and then waiting a few months before trying to become pregnant. Hormone therapy can then be started again after the baby is born.

Keep in mind that the advice about waiting 2 years is not based on data from any clinical trials. And some breast cancers can come back after the 2-year mark, so every case is different. Your decision should take into account many things, including your age, desire for more pregnancies, type of breast cancer, and the risk of the cancer coming back early.

If I get pregnant, would my history of breast cancer put my baby at risk?

Having a history of breast cancer does seem to be linked to an increased risk of some possible complications of pregnancy, including pre-term delivery, having a low-birth-weight baby, and the need for a cesarean section (C-section).

But research has not found that a woman’s past breast cancer has any direct effect on her baby. There is no increased rate of birth defects or other long-term health concerns in children born to women who have had breast cancer.

Could breast cancer treatment affect my unborn baby?

If you are still getting any type of treatment for breast cancer, including chemotherapy, hormone therapy, targeted therapy, or immunotherapy, talk to your doctor before trying to become pregnant. Many of these drugs might affect a growing fetus, so it is safer to wait until all treatment is complete before getting pregnant.

It’s also important to remember that stopping treatment early can increase the risk of the cancer growing or coming back. See Treating Breast Cancer During Pregnancy for more on this.

Can I breastfeed after breast cancer treatment?

If you have had breast surgery and/or radiation, you might have problems breastfeeding from the affected breast. This might include reduced milk production in that breast as well as structural changes that can make breastfeeding painful, or make it harder for the baby to latch onto the breast. Still, many women are able to breastfeed.

If you are still taking any medicines to treat your breast cancer (such as hormone therapy), it’s very important to talk with your doctor before trying to breastfeed. Some drugs can enter the breast milk and might affect the baby.

Talk to your doctor

If you have or have had breast cancer and are thinking about having children, talk with your doctor. Ask how the cancer and its treatment might affect your chances for pregnancy, as well as if being pregnant could affect your risk of the cancer coming back.

In many cases, counseling can help you sort through the choices that come with surviving breast cancer and planning a pregnancy.