A new study shows there is little evidence that chemotherapy treatments on a pregnant woman will negatively impact her unborn child's health, Baptist Press reports. The research on more than 400 European women with breast cancer showed their babies weighed less but were not at a greater risk for birth defects, blood disorders or hair loss. Premature birth, not chemotherapy, actually caused the babies' low birth weight in the study, according to the German Breast Group, which led the research. However, the group acknowledged more research was needed to determine if chemotherapy could cause physical or mental problems for a child later in life. In the past, physicians have told women with breast cancer that chemotherapy could harm their unborn children -- and sometimes recommended abortion -- but this study, among others, has shown such treatments after the first trimester can be safe for both the babies and their mothers.