Chemotherapy During Pregnancy Doesn't Cause Complications, Study Says

Aug. 16, 2012 — -- There is growing evidence that pregnant women with cancer aren't putting their babies at risk by undergoing chemotherapy treatments.

A new study that followed more than 400 pregnant women in Europe who were diagnosed with breast cancer, found little to no evidence of negative health effects on infants whose mothers underwent chemotherapy -- good news for the one in a thousand women who are pregnant and also suffering from cancer.

Infants whose mothers were treated with chemotherapy weighed less than those that weren't exposed to chemotherapy, but they were not at higher risk of birth defects, blood disorders or loss of hair.

According to the German Breast Group, which led the study, premature birth not the chemotherapy treatment was responsible for babies being born at a low birth weight and other complications.

"More complications were reported in the group of infants exposed to chemotherapy than in the group not exposed to chemotherapy," the study said. "However, most complications were reported in babies who were delivered prematurely, irrespective of exposure to chemotherapy."

Incidences of pregnant women with cancer are growing and it may be because many women are delaying childbirth until later in their lives.

"I would say it is an increasing problem because people are generally delaying pregnancy," said Dr. Stephanie Bernik, chief of surgical oncology at Lenox Hill Hospital in New York. "Women want to have careers before they start a family, so women are getting pregnant later."

Additionally, pregnant women are often diagnosed with cancer at a more advanced stage because cancer symptoms can sometimes be mistaken for signs of pregnancy, making treatment more complex, Bernik said.

Now, a small body of scientific research has increasingly brought hope to women who are pregnant with cancer or those who become pregnant after a cancer diagnosis.

In the past, women have been told by their doctors that chemotherapy could harm their baby and were sometimes advised to terminate the pregnancy.

However, recent studies have found that chemotherapy treatment after the first trimester -- when most of the baby's critical growth occurs -- can be safe for baby and mother.

"Ideally, you would avoid chemotherapy in the first trimester of pregnancy," Dr. Bernik said. "The thought is that the fetus is really developing at that stage and the organs are being developed."

It was also initially feared that the high hormone levels present during pregnancy could cause a specific kind of hormone-sensitive breast cancer to reoccur. But a recent, first-of-its-kind study found that it is safe for women to become pregnant after they were treated with this form of cancer -- which accounts for about 60 percent of all breast cancer cases.

This growing evidence may play a critical role in giving doctors confidence to treat pregnant cancer patients, said Dr. Elyce Cardonick, a maternal fetal medicine physician at Cooper University Hospital in New Jersey.

"The first time someone experiences a patient who is pregnant they may be very fearful to treat them," said Cardonick, who maintains a registry of pregnant cancer patients that tracks their progress during and after their pregnancy. "When that oncologist or a gynecologist has a second patient, you get a little more comfortable. Each physician might only see one or two patients like this in their careers; that's why it's important to maintain a registry."

The study by the German Breast Group confirmed other research indicating that chemotherapy treatments carry fewer risks to an unborn child than was originally assumed. But more research needs to be done on the potential physical and mental effects of chemotherapy drugs on a child later in its life.

"The role of chemotherapy is to save the patient to be a mom," Cardonick said. "It's a risk-to-benefit ratio. Nothing is 100 percent safe."