Herceptin and Pregnancy: An Overview
Herceptin® (
trastuzumab) is generally considered unsafe for women who are pregnant. In animal studies that looked at the effects of Herceptin during pregnancy, the drug did not cause any problems.
Herceptin and Pregnancy Category D
The U.S. Food and Drug Administration (FDA) uses a pregnancy category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category D is a classification given to medicines that have been shown to present a risk to the fetus in studies of pregnant women but may still offer benefits that outweigh the risks the drug presents.
Herceptin appears to increase the risk of low amniotic fluid in pregnant women. In many cases, amniotic fluid increased once Herceptin was stopped. In one case, the low amniotic fluid recurred after Herceptin was started again (this strongly suggests that the problem was caused by Herceptin).
Pregnancy Category D medicines (including Herceptin) may still be given to a pregnant woman if the healthcare provider believes that the benefits to the woman outweigh the possible risks to the unborn child. Dealing with (and treating) cancer in pregnant women is a difficult situation, often without any clear answers. Your healthcare provider can help you think through the various treatment options you may have.
Women who take Herceptin during pregnancy should be monitored for low amniotic fluid.