A prescription drug whose generic name is isotretinoin, a synthetic derivative of vitamin A used to treat severe types of cystic acne unresponsive to other medications. Known from the time of its approval to cause birth defects, Accutane continued to be used by many women who became pregnant. Often it was used in the first weeks after conception, before the pregnancy was recognized. Among the birth defects associated with fetal exposure to Accutane are hydrocephaly (increase in the amount of fluid in spaces in the brain), a very small head (microcephaly), various ear and facial abnormalities, heart defects, and mental retardation. Women are advised to have a pregnancy test performed at least two weeks before starting Accutane therapy, to start the therapy on the second or third day of their next menstrual period, and to use two reliable forms of contraception simultaneously during therapy if they do not abstain from sexual intercourse.