Chemo During Pregnancy Doesn't Seem to Harm Newborn

WEDNESDAY, Aug. 15, 2012 (HealthDay News) -- Women who need chemotherapy for breast cancer during pregnancy should not compromise their treatment or deliver their babies early, a new study says.

In the study, published online Aug. 15 in The Lancet Oncology, researchers in Germany found that babies born to breast cancer patients who had chemotherapy while they were pregnant were not at greater risk for complications. They also found that the babies who did suffer from complications were premature, regardless of whether or not they were exposed to chemotherapy.

"Our findings emphasize the importance of prioritizing a full-term delivery in women who undergo chemotherapy while pregnant," study leader Sibylle Loibl, of the German Breast Group, said in a journal news release.

"Illness and mortality in newborn babies is directly related to gestational age at delivery," Loibl stressed. "This is an important clinical message because the decision to deliver the fetus preterm is often taken without medical indication. Our work suggests that treating patients with breast cancer while pregnant is possible, and there is no need to interrupt the pregnancy or receive inferior therapy."

In conducting the study, the researchers examined more than 400 European women diagnosed with early stage breast cancer while they were pregnant. Of these women, 48 percent underwent chemotherapy during their pregnancy.

The infants exposed to chemotherapy in the womb had, on average, a lower birth weight than other infants who were not exposed to the cancer drugs, the study found. The authors pointed out, however, that that was about the only noticeable difference among the babies, and the number of chemotherapy cycles the women received did not appear to affect their babies' birth weight.

Complications among the infants were more often associated with preterm delivery, regardless of exposure to chemotherapy in the womb, the researchers noted. Half of the women in the study delivered prematurely. Of these, 23 percent gave birth before they were 35 weeks pregnant. In comparison, about 10 percent to 15 percent of infants are born preterm in the general population, Loibl pointed out in the news release.

"If our findings are confirmed by other studies, breast cancer during pregnancy could be treated as it is in nonpregnant women without putting fetal and maternal outcomes at substantially increased risk," Loibl concluded.

In response to the study's findings, Dr. Olivier Mir, of the Cancer Associated with Pregnancy Network in France, said more research is needed to determine the best chemotherapy doses for pregnant women as well as the long-term risks children face from having been exposed to the cancer drugs in the womb.

More information

The U.S. National Library of Medicine has more about chemotherapy.