目的 调查发生前置胎盘的相关危险因素，为其预防和治疗提供理论依据。方法 收集420例前置胎盘和1260例正常孕妇的临床资料，建立数据库，应用Logistic回归分析方法分析临床相关危险因素。结果 剖宫产次数(OR=2.656，95%CI:1.457~5.536)、双胎及多胎妊娠(OR=2.325，95%CI: 1.643~5.673)、子宫内膜炎(OR=4.646，95%CI:1.642~6.534)、吸烟或被动吸烟(OR=3.453，95%CI: 1.653~7.562)、流产次数(OR=2.267，95%CI:1.785~6.545)与引发前置胎盘密切相关，并且前置胎盘可以导致胎盘粘连、胎盘植入、产后出血、早产、死胎等。结论 剖宫产次数、吸烟或被动吸烟、流产次数、双胎及多胎妊娠、子宫内膜炎是引发前置胎盘的相关危险因素。

Objective To investigate and analyse the clinical associated risk factors which affect the placenta praevia, providing theoretical basis for early prevention and treatment of this disease. Methods Clinical data of 420 cases, diagnosed as having placenta praevia, were collected to establish database, and logistic regression analysis was conducted to analyze the clinical associated risk factors. Results The number of cesarean section (OR=2.656, 95%CI: 1.457-5.536 ), twin and multiple pregnancy (OR=2.325, 95%CI: 1.643-5.673), endometritis (OR=4.646, 95%CI: 1.642-6.534) , smoking (OR=3.453, 95%CI: 1.653-7.562), number of abortion (OR=2.267, 95%CI: 1.785-6.545), were closely related to placenta praevia and placenta praevia can lead to adherent placenta, placenta accreta, postpartum hemorrhage, premature birth, stillbirth and other adverse pregnancy outcomes. Conclusions Uterine incision delivery, smoking, abortion, multiple pregnancy, and endometritis are related risk factors of placenta praevia.