OBJECTIVE Inherited thrombophilia is associated with thromboembolic events and/or poor obstetric outcome. We evaluated the pregnancy outcome in women with inherited thrombophilia treated with low-molecular-weight heparin (LMWH). METHODS 38 thrombophilic women with a history of thromboembolic events and/or poor obstetric outcome were treated during their 39 consecutive pregnancies with LMWH from pregnancy verification until 4-6 weeks in puerperium. A fixed dose of enoxaparin 4,000 IU/day (except 1 case who required nadroparin 0.3 ml/day) was administered in most cases, adopting a higher dose (6,000 IU/day to 6,000 IU twice a day) in those with previous thromboembolic events. RESULTS In the treated women, all had a good obstetric outcome, whereas in the previous untreated pregnancies (n = 78), the rate of fetal loss (early and late) was 76.9%, only 12 live infants survived (66.6%). Moreover, birth weight resulted significantly higher in live infants born to treated pregnancies in comparison to that of previous untreated pregnancies (p = 0.009). No maternal thrombosis or major bleeding complications were recorded. CONCLUSIONS The treatment with LMWH improved pregnancy outcome resulting effective and safe in thrombophilic women with a history of thromboembolic events and/or poor obstetric outcome.