Thromboprophylaxis After Surgery for Gynecologic Malignancy in China

Inclusion Criteria: * Patients of ovarian cancer, cervix cancer or endometrial cancer; * Age ≤ 70 years; female, Chinese women; * Initial treatment is surgery; * Laboratory tests: WBC ≥ 4×10(9)/L, NEU ≥ 2×10(9)/L, PLT ≥ 100×10(9)/L, serum bilirubin ≤ 1.5 times the upper limit of normal, transaminase ≤ 1.5 times the upper limit of normal, BUN, Cr ≤ normal * No prior pharmacologic prophylaxis; * Provide written informed consent. Exclusion Criteria: * PLT ≤ 75×10(9)/L * Vascular injury * History of thrombosis * Liver and kidney dysfunction * Concurrently participating in other clinical trials * Unable or unwilling to sign informed consents; * Unable or unwilling to abide by protocol.