[The use of low-molecular heparin for anticoagulation in pregnancy].

A 26-year-old woman, on bedrest since the 6th week of pregnancy because of threatened abortion, developed thrombosis in the left iliac, superficial femoral and common femoral veins with small pulmonary emboli in the 11th week. Inhibitor deficiency was excluded. The thrombosis was only partially recanalized by unfractionated heparin at therapeutic dosage (38,400 IU per 24 h). As thrombolysis treatment and oral anticoagulation were contraindicated because of the threatened abortion, coagulation with low molecular weight heparin (LMWH) was started in the 18th week (5000 anti-Xa units daily subcutaneously). Maximal anti-Xa activity in plasma never exceeded 0.3 U/ml and there were no complications. The patient was delivered of a healthy girl (2,660 g, 48 cm) by caesarean section in the 37th week. Immediately post-partum LMWH was demonstrated with an anti-Xa activity of 0.3 U/ml in maternal blood, but none in simultaneously obtained cord venous blood. This case suggests that treatment of phlebothrombosis with LMWH is a reasonable measure even during pregnancy.