Pregnant women with illness require efficacious and safe drug therapy during pregnancy; however, their treatment is often hindered by a lack of information regarding the use of medications during pregnancy. Ethical challenges are encountered in conducting drug trials in pregnant women, who are often excluded from participation due to fear of harm to the fetus. However, as the health of the fetus is ultimately affected by that of the pregnant woman, inclusion of pregnant women in studies of medications that they may require for their own benefit may also benefit the unborn child. The principle of autonomy argues for the pregnant woman being able to make an informed choice to take part in a clinical trial, and the principle of justice dictates that she not be denied the benefits of drug research.