News > Infants exposed to chemotherapy during pregnancy develop normally

Infants exposed to chemotherapy during pregnancy develop normally


A recent study of the long-term outcomes, or effects, for children exposed to chemotherapy during pregnancy has shown that most have normal heart, brain and cognitive functions despite exposure to treatment.

Published in Lancet Oncology by a group of Belgian researchers, the study advances what is known about a significant concern for pregnant women affected by cancer.

Background and reason for the study

Of every 2,000 pregnancies, one or two expectant women will be diagnosed with cancer and need treatment during pregnancy. About 40 percent of those diagnoses involve breast cancer.

Women and their doctors used to consider terminating pregnancies rather than expose the fetus to powerful medicines or risk the women’s survival by delaying treatment. Now, increasingly, chemotherapy is used in pregnant women after the first trimester. Yet the effects of that treatment on children exposed before birth have not been well-studied.

The researchers wanted to learn whether chemotherapy influences the general health, heart function or brain and nervous system (neurological) development of children born to mothers who were pregnant while in cancer treatment.

Study structure

Because of the relative rarity of cancer during pregnancy, this multi-center study looked at only 70 children from 68 pregnancies (there was one set of twins). All had been exposed to chemotherapy during pregnancy. Breast cancer was the most common diagnosis for mothers in the study.

Children were assessed at birth, at 18 months or up to 18 years old. They received testing for their nervous systems, hearts, mental processing and developmental progress. Those five years old or older also had their hearing, verbal learning, memory, attention and behavior measured.


Babies in the study were born at the median or midpoint age (some older, some younger) of 35.7 weeks, compared to the standard of about 40 weeks.

Despite prenatal exposure to chemotherapy, the children scored within normal ranges for heart size and function as well as neurocognitive abilities. Their behavior, general health, hearing and growth were similar to children in the general population. The researchers noted “subtle changes” in heart and neurocognitive measurements that they said needed longer follow-up to assess.

Some children in the study were born prematurely after doctors induced labor. Those children had lower cognitive development scores than did the full-term babies studied. The authors urged avoiding early delivery when possible. Preterm delivery may be recommended if the mother’s treatment needs are urgent.

What this means for you

This study offers reassurance if you are pregnant, diagnosed with breast cancer and need chemotherapy. Most children exposed to chemotherapy medicines during pregnancy showed long-term normal development.

Talk with your doctor about your concerns for your baby and yourself. Here are some suggested questions to ask:

  • I think I am [fill in the blank] weeks pregnant. How will that affect my treatment schedule or plan?
  • How would I be treated if I were not pregnant?
  • Has the chemotherapy in my treatment been given to other pregnant women? What have been the results for them and their babies?
  • Will I need to have an early delivery? If so, why? Can it be avoided?
  • What are the risks to my and my baby’s health if I put off chemotherapy until after I give birth?

For more information and support, visit Hope for Two...The Pregnant with Cancer Network . This organization connects women who are pregnant with cancer to share experiences with others who've had the same cancer during pregnancy.


F Amant, K Van Calsteren, MJ Halaska, et al.  Long-term cognitive and cardiac outcomes after prenatal exposure to chemotherapy in children aged 18 months or older: an observational study  Lancet Oncology 2012; 13(3): 256-264.


This article was supported by Cooperative Agreement Number DP11-1111 from The Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention.