Cancer Care for Pregnant Moms Won't Harm Baby, Study Says

By Gil Ross — Sep 30, 2015
Women diagnosed with cancer while pregnant have plenty to worry about. A new study may help reduce that burden, since it shows that typical cancer treatments may have no significant adverse effect on their fetus or newborn.

Pregnant!While being diagnosed with cancer is tremendously disconcerting at any time, its concern is redoubled when that diagnosis is rendered to a woman who is pregnant.

Among the many thoughts swirling through her mind, one is likely paramount: Can I proceed with the appropriate treatment to save my life, without harming my growing baby?

Often, both the patient and her doctor resort to desperate measures to avoid potentially damaging chemotherapies or radiation impacting the fetus. Those would include either early delivery or termination of the pregnancy, neither of which are a preferred option.

But now, findings in a new study might help to relieve this terrible burden.

The study showed that among a cohort of 129 children born to mothers who were diagnosed with cancer while pregnant, there were no significant differences in birth weight, cognitive, or cardiac function -- when tested at birth, at 18 months and 36 months -- as when compared to a control group whose mothers were not cancer patients.

The study, entitled Pediatric Outcome after Maternal Cancer Diagnosed during Pregnancy, was led by Frédéric Amant, M.D., Ph.D.; Tineke Vandenbroucke, M.Sc.; and Magali Verheecke, M.D of the Katholieke Universiteit Leuven, Belgium; and a multinational group called the International Network on Cancer, Infertility, and Pregnancy (INCIP). It was published this week in an early release in the New England Journal of Medicine, after the results were presented at the European Cancer Congress in Vienna.

During pregnancy, 96 children were exposed to chemotherapy, 11 to radiotherapy, 13 to surgery and two to "other drug treatments," while 14 had no treatment exposures. Of note, none of the expected mothers received any cancer-directed treatments during their first trimester. More than half of the women had breast cancer; 16 percent had "blood cancers."

Dr. Amant told the New York Times, [t]o some extent, it s surprising because cancer treatment is quite toxic, and we know most chemotherapy drugs cross the placenta.

More than 60 percent of children of mothers with cancer were born earlier than 37 weeks, compared with roughly eight percent in the general population. Most mothers were induced into labor so cancer treatment could continue. Dr. Amant said he hoped his team s data would persuade clinicians to stop this practice. (Prematurity was correlated with worse cognitive functioning among the children born early.)

Prematurity is a problem for these children," Dr. Amant said, "but chemotherapy is not.

In an accompanying editorial to the study, Dr. Michael F. Greene, the chief of obstetrics at Massachusetts General Hospital (who was not involved with the study), expressed cautious optimism about the study, saying it offered reassurance to pregnant women undergoing cancer treatment that it s not inevitably a horrible problem for their offspring.

Another expert cited in the Times article, Dr. Elyce H. Cardonick, a maternal-fetal specialist at Cooper Medical School of Rowan University in Camden, N.J., supported Dr. Amant's conclusion.

The main message of this study is that termination of pregnancy is not necessarily warranted," said Dr. Cardonick, who was not involved in the new research, "and that early preterm delivery to be able to do cancer treatment isn t warranted, either.

While likely to offer much-needed comfort to women in such a distressing situation, the study has its limitations. The different classes of chemotherapy agents were not distinguished, and indeed there were not enough subjects in each drug class to extract much cogent information.

Moreover, no "novel" or "targeted" anticancer therapies were studied. And the general term "cancer" is not necessarily applicable to each and every woman with that generic diagnosis, as different cancers have vastly different effects on mother and fetus regardless of treatments.

In conclusion, the authors said "[o]ur data suggest that the diagnosis of cancer during pregnancy is not necessarily an indication to terminate the pregnancy. Although caution is always indicated, treatment of the maternal cancer in the second trimester or later may not be harmful to the fetus.

"Pregnant women may be informed that the likelihood of prematurity is higher than that in the general population, but among preterm babies, the child is unlikely to have unique problems more serious than those of preterm babies born of women without cancer during pregnancy."