LONDON — Researchers have encouraging news for women who find themselves in a frightening situation: having cancer while pregnant. Studies suggest that these women can be treated almost the same as other cancer patients are, with minimal risk to the fetus.
Only about 1 in 1,000 pregnant women face this dilemma, but doctors fear that more will because the risk of cancer rises with age, and more women are delaying having children until they’re older.
Doctors have long worried about how to balance treating a pregnant woman with cancer and the need to protect her fetus from the effects of toxic cancer drugs and radiation treatments, and whether it is safe to continue a pregnancy in certain situations.
A series of papers in the journals Lancet and Lancet Oncology published Friday make several key contributions:
• A Belgian-led study of 70 children in Europe exposed to chemotherapy while they were in the womb found they developed just as well as other children, according to tests on their hearts, IQ and general health. They were assessed at birth, 18 months and every few years until age 18.
• Chemotherapy after the first trimester is possible, using extra ultrasounds to ensure the baby is developing properly. Radiation therapy is best done in the first two trimesters, when the baby is small enough to be covered with a lead blanket, according to a review of previous studies, led by Belgian researchers.
• Ending the pregnancy doesn’t improve chances for the mother, the same study found.
• The type of cancer seems to matter: An Israeli analysis of past research suggested pregnant women with blood cancers might want to terminate an early pregnancy when chemotherapy can’t be delayed.
Dr. Richard Theriault, a professor of medicine at the MD Anderson Cancer Center in Texas, said he hoped the papers would change how doctors treat pregnant cancer patients.
He said the placenta seems to act as a filter for chemotherapy drugs, restricting their effects on the fetus. “There’s the phenomenon of the bald mother who gives birth to a baby with a full head of hair,” he said. “It seems to suggest not as much gets to the baby as we thought.”
That was certainly the experience for Caroline Swain, who was diagnosed with breast cancer while pregnant with her second son. She had her left breast and many lymph nodes removed and had to wait until her fetus was 12 weeks old before starting chemotherapy.
“I was just so grateful it was possible to have treatment and keep my baby,” said Swain, 45, who lives near London. “I was scared that my child wouldn’t remember me if something happened to me.”
