Previously asymptomatic mitral stenosis can lead to remarkably sudden development of life-threatening pulmonary edema in pregnancy and the patients, often immigrants from the developing world, may be unaware that they have heart disease. Diagnosis and treatment need to be rapid and effective. Left ventricular outflow tract obstruction may also lead to trouble in pregnancy with the development of angina and left ventricular failure. Regurgitant valve disease is much better tolerated in pregnancy than valvular stenosis, but mitral valve repair, usually feasible for nonrheumatic prolapsing mitral valves, should be carried out before pregnancy if regurgitation is severe. The treatment of women with Marfan's syndrome who already have aortic root widening but desire children remains very difficult, both with regard to the mother's safety and in relation to the dominant inheritance of the condition. Advice to women with artificial valves desiring pregnancy remains controversial, with continuation of warfarin increasingly favored over transfer to heparin in Europe. The use of bioprostheses in young women anticipating future pregnancy is also fading due to mounting evidence of accelerated deterioration of such bioprostheses during pregnancy.