NEW YORK — It is among the most delicate and difficult dilemmas in medicine: Should a pregnant woman who has received a cancer diagnosis begin treatment before her child is born? Some hesitant doctors counsel women to deliver preterm or even terminate the pregnancy first.
But a new study of more than 100 children who were exposed to cancer treatment during the last two trimesters of their mother’s pregnancy showed they had normal cognitive and cardiac function, researchers reported Monday.
“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,” said Dr. Elyce H. Cardonick, a maternal-fetal specialist at Cooper Medical School of Rowan University in Camden, N.J., who was not involved in the new research.
The study, published in The New England Journal of Medicine, was presented Monday at the European Cancer Congress in Vienna.
“We didn’t find any difference in cardiac functioning or cognitive function between children exposed to cancer treatment in utero and the control group,” said Dr. Frédéric Amant, lead author of the study and professor of obstetrics and gynecology at the Katholieke Universiteit Leuven in Belgium.
“To some extent, it’s surprising because cancer treatment is quite toxic,” he said, “and we know most chemotherapy drugs cross the placenta.”
None of the women underwent chemotherapy in the first trimester, because the risk of causing serious birth defects is greatest then. Instead, researchers assessed mental development of 129 children who had been exposed to chemotherapy, radiation, or surgery later in pregnancy, as the fetal brain continues to develop.
The cognitive findings were based on a neurological exam and a test called the Bayley Scales of Infant Development that researchers conducted on the children at 18 months, 3 years, or both.
More than half of the mothers-to-be had breast cancer, and 16 percent had blood cancers.
More than 60 percent of children of mothers with cancer were born earlier than 37 weeks, compared with roughly 8 percent in the general population. Most mothers were induced into labor so cancer treatment could continue. Amant said he hoped his team’s data would persuade clinicians to stop this practice.
Some common chemotherapy agents like doxorubicin can damage the heart muscle in adults, depending on the dose. So the researchers assessed the hearts of 47 of the 129 children in the study using electrocardiography and echocardiography.
At age 3, “the cardiac development of these babies was pretty normal,” said Dr. Michael F. Greene, chief of obstetrics at Massachusetts General Hospital, who was not involved in the study. They did not have significant differences in the size of the heart chambers or the muscle’s ability to pump blood.