The risks to the mother and fetus of valve thrombosis and anticoagulation dur- ing pregnancy with a mechanical valve must be weighed against the reduced durability of bio- prosthetic valves in young women. For women considering a mechanical prosthesis, it has been proposed that they undergo a preoperative trial of anticoagulation with warfarin to assess the dose needed to achieve a target INR. In 1 small study, women who required <5 mg daily of warfarin and then underwent subsequent mechanical AVR did not experience maternal or fetal complica- tions during pregnancy.15 Larger trials are needed, however, before this becomes standard practice. Shared decision-making with a cardiologist with expertise in the management of severe valve dis- ease during pregnancy allows discussion of these issues in women of childbearing age before valve surgery, even when pregnancy is not planned in the near future.1,14,16 3. Severe rheumatic MS presents a significant risk of maternal adverse outcome during pregnancy. In asymptomatic women with severe rheumatic MS (mitral valve area 1.5 cm2 , Stage C) and favor- able valve morphology who are considering preg- nancy, PMBC results in an increase in mitral valve area and reduction in transmitral gradient, which makes the patient more resilient to the hemody- namic load of pregnancy.1 5,12,13 4. Pregnant women with a bioprosthetic valve, compared with women with a mechanical valve who are on anticoagulation, have a lower risk of valve thrombosis, excessive bleeding, and fetal and maternal death.14 The Ross procedure is an alternative if performed in women with favor- able anatomy and at centers with expertise in the procedure. 5. Most patients with mild to moderate AS can tol- erate the hemodynamic changes of pregnancy without cardiovascular events. 