THROMBOPROPHYLAXIS WITH LOW-MOLECULAR-MASS HEPARIN, FRAGMIN (DALTEPARIN), DURING PREGNANCY - A LONGITUDINAL SAFETY STUDY

Twenty-five women with previous verified thromboembolic complications were treated with dalteparin (Fragmin(R)) during pregnancy and puerper ium. Women with known hereditary thrombophilia (antithrombin, protein C and protein S deficiencies) or with phospholipid antibodies were exc luded. The dose at entry was calculated according to body weight and t hereafter monitored by anti-FXa activity aiming at 0.20-0.40 IU/ml pla sma 3 h post injection. Dalteparin or dextran was used during delivery . Twenty-two women completed the study and 14 of these could be given the same dose throughout pregnancy. There was an increased dose respon se postpartum. There were no thromboembolic recurrences or severe blee ding complications. The level of antithrombin activity remained normal . Our thrombosis-prone pregnant women had initially increased levels o f thrombin markers but no further increase was observed during the dal teparin thromboprophylaxis. Retrospectively, three heterozygous and th ree homozygous individuals for the FV Leiden mutation leading to activ ated protein C resistance were identified. In conclusion, dalteparin c ould safely be used as thromboprophylaxis during pregnancy in these th rombosis-prone women. Women weighing 50-79 kg at entry could be treate d with 5000 IU of dalteparin once daily during pregnancy, without moni toring. Postpartum, many of the women were given a reduced dose. (C) 1 998 Rapid Science Ltd.