1 % of all pregnancies end in habitual/recurrent abortion. In about half of women with habitual abortions (HAB) hereditary or acquired (antiphospholipid antibodies) thrombophilia are observed. The investigators wanted to test whether antithrombotic treatment (Low-Molecular Weight Heparin, LMWH, ASA or both combined)would prevent these women from a subsequent abortion. Depending on thrombophilic status the women included in one of the three sub-studies: HABENOX 1 (mild, single thrombophilia), HABENOX 2 (no known thrombophilia), HABENOX 3 (moderate to severe thrombophilia, with combined thrombophilia or moderate to high titer antiphospholipid antibodies).