Breast Cancer Treatment During Pregnancy

A different approach to treatment

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Having to treat breast cancer during pregnancy is something that you may worry or even feel conflicted about. Your health and that of your baby both have to be taken into consideration, and typical treatment plans may put those two things at odds. But that doesn't mean you don't have options.

Surgery, chemotherapy, radiation, and hormone therapy may all have their place in your treatment plan, but the timing of certain treatments might have to change. It all depends on the type and location of the cancer and how far into your pregnancy it's diagnosed.

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Chemotherapy During Pregnancy

Chemotherapy can harm a baby's developing organs, so it's not used during the first trimester. It's considered safer in the second and third trimesters.

The drugs used for chemo during pregnancy will depend on the trimester you are in when your treatment begins. Taking certain drugs is riskier during certain trimesters than others.

Anthracycline drugs, including Adriamycin (doxorubicin), are the most commonly used during pregnancy, and they are often combined with Cytoxan (cyclophosphamide). Many studies on FAC chemotherapy—which combines these two drugs with Adrucil (fluorouracil)—have shown that this treatment is safe for your baby. It's rare for miscarriage, premature birth, stillbirths, or birth defects to be associated with FAC treatment.

Chemotherapy can affect your future fertility. Be sure to discuss this possibility with your healthcare provider if you want to have more children.

Taxane regimens aren't generally used during pregnancy. These drugs include Taxol (paclitaxel) and Taxotere (docetaxel). Methotrexate is known to cause miscarriage and birth defects. Thus, it should never be used during pregnancy.

Guard Your Immune System

Chemo lowers your white blood cell count and leaves you and your baby more vulnerable to infection during treatment. Not every baby's immune system will be affected during chemo, but if it is and white cell count remains low after birth, be sure to get treatment.

Many healthcare providers believe it's safe to provide injections of drugs that raise the white blood cell count, such as Neupogen (filgrastim) or Neulasta (pegfilgrastim), during pregnancy.

Surgery During Pregnancy

Surgery during pregnancy is considered safe for the baby, so it's usually the first treatment option for pregnant women with breast cancer, especially the early stages of cancer.

Mastectomy and lymph node removal is the most common breast cancer surgery for pregnant women, especially during the first trimester. This is because it doesn't require radiation afterward, which can harm a baby (more details below).

Breast-conserving surgery, such as lumpectomy and partial mastectomy, may require radiation treatment as a follow-up. These may be performed later in pregnancy and radiation treatments delayed until after childbirth.

General anesthesia is part of whatever type of breast cancer surgery you and your healthcare provider choose. Anesthesia can pose some risks to the baby, so your healthcare providers will need to work together to determine the best time during your pregnancy to schedule the surgery.

Radiation Therapy After Pregnancy

Radiation helps kill any cancer cells that may still be present in your breast, which can prevent a recurrence. However, it can cause miscarriage, birth defects, or slow growth, even if a lead shield is used. As such, this therapy is used only after you give birth.

Not much research has been done on the effect of breast radiation or brachytherapy (very localized radiation) on breasts that have changed as a result of pregnancy. Therefore, it's not known if delayed treatment will be as effective after giving birth as it would otherwise.

It may be comforting to know that research shows that women who delay radiation due to pregnancy don't have worse outcomes than women who get the treatment right away.

Hormonal Therapy After Pregnancy

Tamoxifen is a hormonal therapy that blocks estrogen from breast tissues. It is usually given to women with estrogen-receptor positive breast cancer.

However, it is dangerous to take during pregnancy. Hormone therapy can be given after your baby’s birth to lower your risk of recurrence.

Hard Choices

At a time when you may be very focused on the new life within you, you may be asked to make some hard, personal decisions. While it's far less common than it used to be, you may be asked to consider ending the pregnancy. It's more common when an aggressive type of cancer is diagnosed early in pregnancy.

It's important to note that research has not shown that termination has a beneficial effect on breast cancer outcomes, and it is not usually considered as a therapeutic option.

However, if your cancer is aggressive, was diagnosed late, and you're in need of high-dose chemo and radiation, you might have to discuss the termination of your pregnancy in order to allow for proper treatment. Another option could be early delivery of your baby if you are at a late stage of pregnancy and the baby's chance of survival is good.

All of this, of course, can be quite difficult to take in. Talk with your family, oncologist, and obstetrician to fully understand and consider all your options. The choice is personal and, ultimately, yours.

Breast Cancer Doctor Discussion Guide

Get our printable guide for your next healthcare provider's appointment to help you ask the right questions.

Doctor Discussion Guide Woman

A Word From Verywell

You're being asked to make incredibly difficult decisions, weighing your treatment needs against the risks to your baby. Along with leaning on friends and family, you may want to consider seeing a counselor to help you get through this process emotionally.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Esposito S, Tenconi R, Preti V, Groppali E, Principi N. Chemotherapy against cancer during pregnancy: A systematic review on neonatal outcomes. Medicine. 2016 Sep;95(38):e4899. doi:10.1097/MD.0000000000004899

  2. Monteiro DL, Trajano AJ, Menezes DC, et al. Breast cancer during pregnancy and chemotherapy: A systematic review. Rev Assoc Med Bras. 2013 Mar-Apr;59(2):174-80. doi: 10.1016/j.ramb.2012.10.003

  3. Murthy RK, Theriault RL, Barnett CM, et al. Outcomes of children exposed in utero to chemotherapy for breast cancer. Breast Cancer Res. 2014;16(6):500. doi:10.1186/s13058-014-0500-0

  4. Dawson AL, Riehle-Colarusso T, Reefhuis J, Arena JF; National Birth Defects Prevention Study. Maternal exposure to methotrexate and birth defects: a population-based studyAm J Med Genet A. 2014;164A(9):2212–2216. doi:10.1002/ajmg.a.36625

  5. Cardonick, E, Irfan, F, Torres, N. The use of Neupogen (filgrastim) or Neulasta (pegfilgrastim) during pregnancy when chemotherapy is indicated for maternal cancer treatment. Journal of Cancer Therapy. 2012;3:157-161. doi:10.4236/jct.2012.32021

  6. Keyser EA, Staat BC, Fausett MB, Shields AD. Pregnancy-associated breast cancer. Rev Obstet Gynecol. 2012;5(2):94-9. doi:10.3747/co.22.2338

  7. Keyser EA, Staat BC, Fausett MB, Shields AD. Pregnancy-associated breast cancer. Rev Obstet Gynecol. 2012;5(2):94–99.

  8. American Cancer Society. Treating breast cancer during pregnancy. 2019.

Additional Reading

By Pam Stephan
Pam Stephan is a breast cancer survivor.