PRECONCEPTIONAL counseling is appropriate not only for women with medical complications but for any woman or couple contemplating pregnancy. The internist is in the unique position of seeing patients before conception. Carrier screening for genetic disorders may be offered to specific populations with an increased frequency for a particular disease. Commonly used drugs such as tobacco, alcohol, cocaine, and perhaps caffeine can adversely affect perinatal outcome. Women with medical illnesses such as diabetes mellitus and phenylketonuria have improved pregnancy outcomes with strict periconceptional metabolic control. Patients requiring chronic anticoagulation, seizure prophylaxis, antihypertensive pharmacotherapy, or control of manic-depressive illness may benefit from a change to a more appropriate medication for pregnancy. Periconceptional folic acid supplementation should be recommended for all patients considering pregnancy. The medical community has long recognized the importance of discussing the possibility of pregnancy with women of reproductive age with a variety of medical conditions. In certain