<prompt> The anticoagulant of choice in pregnancy isHeparinWarfarinDicumarolPhenindione  <response>: Heparin 562-KDT 598-KDT6thHEPARIN - is the anticoagulant of choice during pregnancy because it does not cross BBB or placentaAdverse effects1. Bleeding due to overdoses is the most serious complications2. Thrombocytopenia is another common problem3. Transient and reversible alopecia is infrequent4. Osteoporosis5. Hypersensitivity reactionsCONTRAINDICATIONS1. Bleeding disorders, thrombocytopenia2. Severe hypertension risk of cerebral haemorrhage threatened abortion, piles, GI ulcers aggrevated bleeding3. SABE, large malignancies, Tuberculosis hemoptesis4. Ocular and neuro-surgery, lumber puncture5. Chronic alcoholics, cirrhosis, renal failure6. Aspirin and other antiplatelet drugs, should be used very cautiously during heparin therapy 