Abstract： Objective To evaluate the clinical features,diagnostic methods and treatment of venous thromboembolic disease (VTE) during pregnancy.Methods From June 2006 to June 2011,a total of 20 pregnant women were diagnosed VTE at the Department of Obsterics and Gynaecology,Qilu Hospital of Shandong University.Clinical data of these patients were analyzed retrospectively.Results (1) Characteristics of patients:the symptoms of all the 20 patients commenced in pregnancy.Of these,6 (30％) happened in the first trimester,7 (35％) in the second trimester,and 7 (35％) in the third trimester.Twelve (60％) patients went to hospital in one week after they had symptoms,while 8(40％ ) went to hospital after one week.(2)Clinical manifestation:18 patients were diagnosed deep venous thrombosis (DVT),one was diagnosed pulmonary embolism (PE).One patient was diagnosed DVT and PE simultaneously.Among the 19 DVT patients,16 (16/19)were on the left side,3 (3/19)were on the other.They all came with sudden swelling and pain of the affected lower extremity.In 17(17/19) patients,the circumference differences between two legs were beyond (4.0 ±0.5) cm.In all the 20 patients,12 (60％) had elevated plasma level of D-dimmer.The diagnosis of DVT was made mainly by a Doppler ultrasound.Among the 19 DVT events,7 (7/19) were proximal DVT,2 (2/19) were distal,and 10( 10/ 19) were mixed type.(3)Anticoagulant therapy:patients with VTE during pregnancy were treated with low molecular weight heparin (LMWH) (enoxaparin,once 1 mg/kg subcutaneous,twice a day).After delivery,patients were treated with subcutaneous LMWH and warfarin simultaneously for at least 5 days,until the prothrombin time-international normalized ratio ( PT-INR ) was ＞ 2.0 for 24 hours.( 4 ) Thrombolytic therapy:for most patients with VTE,we are against the routine use of thrombolytic therapy,especially before delivery.For patients with acute massive PE,urokinase of 600 000 units intravenously daily was recommended for 3 days.For those patients with DVT whose standard anticoagulation therapy was ＜ 30 days,an inferior vena cava filter(IVCF) placement was recommended before delivery or abortion.If it was ≥30 days,IVCF was not recommended as a routine,and anticoagulant therapy was used 24 hours after delivery.If there was no recurrent DVT or PE,IVCF was retrieved routinely in 12 days.(5)Outcome:among patients treated with LMWH (95％,19/20).Three received IVCF placement,which was retrieved successfully in 12 days,with no interventional complication.All patients recovered well after 2 weeks,and the circumference differences between two legs were within (2.0 ± 0.3 ) cm.Of the 18 patients maintained to the third trimester,17 received anticoagulant therapy,and no abnormal findings were found during antenatal examination.Ten patients received cesarean section (50％,10/20),while 8 had vaginal delivery (40％,8/ 20).Neither neonatal asphyxia nor malformation was observed.The patients were followed-up for 1 - 24 months,no venous thrombus extension was found in 17 cases by Doppler ultrasound,thrombus disappeared in 2 cases of distal DVT after 4 weeks and 8 weeks respectively.By echocardiography,the pulmonary arterial pressure of the 2 patients with PE was found normal 3 months after hospital discharge.There was no maternal death during the study,no recurrent PE or bleeding occured.Conclusions LMWH is safe and effective for VTE during pregnancy.Routine use of thrombolytic therapy is not recommended.VTE in pregnancy is not the absolute indication of termination of pregnancy.The indication of an IVCF placement should be stricter,and a retrievable suprarenal IVCF is recommended under certain circumstances.