Most cancer treatment during last two trimesters doesn't harm fetus, study says Premature birth is a greater concern

Children of women who received cancer treatment during the last two trimesters of pregnancy have normal cognitive and cardiac function, according to a new study in NEJM.

The findings may help families deal with the heart-wrenching question of how to treat pregnant women with cancer. "Some hesitant doctors counsel women to deliver preterm or even terminate the pregnancy" before beginning treatment, Catherine Saint Louis writes in the New York Times.

Details of the study

For the study, researchers assessed the development of 129 children born in Belgium, the Czech Republic, Italy, and the Netherlands to women who had cancer during pregnancy, compared with similar children born to healthy mothers. Researchers performed cognitive tests on the children at 18 months, three years, or both, and gave a subset of 47 children electrocardiography and echocardiography tests to assess cardiac function.

While 14 women with cancer received no treatment, 89 of the children had been exposed to chemotherapy in utero, four to radiotherapy, seven to both, 13 to surgery, and one each to separate cancer drugs. All of the women who received cancer treatment did so during the last two trimesters of pregnancy, and the most common cancers treated were breast and blood cancer.

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Overall, the study found children born to women who had undergone cancer treatment showed no cognitive or cardiac deficits compared with similar children with the same gestational age. Frederic Amant, a professor and gynecological oncologist at University Hospitals Leuven in Belgium who led the study, says, "Our results show that fear of cancer treatment is no reason to terminate a pregnancy, that maternal treatment should not be delayed, and that chemotherapy can be given."

Prematurity

More than 60% of mothers with cancer in the study delivered earlier than 37 weeks, compared with about 8% of mothers in the general population. Amant says he hopes his team's data will help persuade doctors to stop the practice of inducing labor early so cancer treatment can continue.

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Children in both groups suffered cognitive deficits from premature births: Every week in the womb led to about two more points on the Bayley Scales of Infant Development, which was used as a cognitive assessment. "Prematurity is a problem for these children, but chemotherapy is not," Amant notes.

Amant says the results were "surprising" because many cancer treatments are known to be toxic and most chemotherapy drugs cross into the placenta. However, he cautions that the study includes several different types of chemotherapy and does not "guarantee that all types of chemotherapy are safe."

Reaction

In an editorial accompanying the study, Michael Greene, chief of obstetrics at Massachusetts General Hospital, writes that the research may provide reassurance to women undergoing cancer treatment that "it's not inevitably a horrible problem for their offspring."

Elyce Cardonick, a maternal-fetal specialist at Cooper Medical School, agrees that the study suggests pregnant women with cancer have more options than they may think. "The main message of this study is that termination of pregnancy is not necessarily warranted, and that early preterm delivery to be able to do cancer treatment isn't warranted, either," she says (Saint Louis, New York Times, 9/28; Kelland, Reuters, 9/28).