Hello palvinder, thanks for the query. While it is very important to be on acitrom for you to prevent thrombotic complications in pregnancy, it is equally important to prevent significant malformations in the baby due to acitrom. Please consider the following facts. 1. The fact that you were on acitrom says you must have had mechanical prosthetic valve replacement rather bio prosthetic valve where anti coagulation may not be required at all. 2. The use of any anticoagulants in pregnancy is a risk for bleeding at the placental site and subsequent miscarriage, preterm birth and low birth weight in the baby. In such a circumstance, using acitrom ( warfarin) in the first trimester poses further risk of malformations in the baby. And hence once pregnancy is detected, acitrom is usually replaced with either low molecular weight heparin or unfractionated heparin till 12 to 13 weeks to avoid teratogenicity. As acitrom is the best anticoagulant used to prevent thrombotic complications ( the risk for blood clotting in pregnancy is magnified 6 fold), it can be restarted following 12 weeks or continued with heparin depending on physician judgement. However, one must know that the risk for valvular thrombosis increases about 7% if only heparin is used during this period. 3. Although it is very hard to determine the effects of acitrom on baby so early, as you have discontinued it in the very early stage and the dose is less 5mg) there may not be any harm on the baby. But I must warn you that you need to see your doctor for a detailed discussion and for anticoagulant replacement with heparin which is of utmost importance till 12 weeks following which you can be on warfarin again. Continued therapy during breast feeding is safe and encouraged. Hope this helped. Take care.