摘要目的:探讨妊娠早期阴道流血特征与先兆流产孕妇发生难免流产的关系。方法:回顾性分析2019年1月至2022年12月重庆医科大学附属妇女儿童医院收治的240例以阴道流血为主要表现的先兆流产孕妇的临床资料。随访其妊娠结局，采用分组分层方法分析年龄、体重指数（BMI）、不良孕产史、妊娠方式、妊娠胎数、流血开始孕周、流血持续时间、绒毛膜下血肿（SCH）面积及感染等对其妊娠结局的影响，单因素及多因素logistic回归分析筛选导致难免流产的高危因素。结果:（1）一般情况：240例妊娠早期阴道流血孕妇的年龄（30.6±4.5）岁；自然妊娠者105例，体外受精-胚胎移植（IVF-ET）者135例；单胎妊娠176例，双胎妊娠64例；无SCH者59例，合并SCH者181例。（2）妊娠结局：总流产率为9.2%（22/240），活产率为90.8%（218/240）。活产孕妇中，存在至少1项妊娠并发症或合并症者占51.8%（113/218），早产率为11.9%（26/218），剖宫产率为57.8%（126/218），产后出血率为1.8%（4/218）。（3）不同分组孕妇的妊娠结局：与自然妊娠组比较，IVF-ET组孕妇的年龄更大、流血开始孕周更早、双胎妊娠率及剖宫产率更高，但流血持续时间更短、SCH面积更小、流产率更低，与非SCH组比较，SCH组孕妇的年龄更小、流血开始孕周更晚、持续时间更长、妊娠期高血压疾病（HDP）的发生率更低，分别比较，差异均有统计学意义（ P均<0.05）。（4）单因素及多因素logistic回归分析结果：BMI≥25 kg/m 2的孕妇流产率高于BMI<25 kg/m 2的孕妇（分别为17.1%、7.5%），自然妊娠者的流产率高于IVF-ET者（分别为13.3%、5.9%），流血开始孕周≥8周者的流产率高于孕周<8周者（分别为14.7%、4.6%），流血持续时间≥10 d者的流产率高于<10 d者（分别为22.7%、4.0%），存在感染者的流产率高于不存在感染者（分别为14.9%、5.5%），分别比较，差异均有统计学意义（ P均<0.05）。BMI≥25 kg/m 2（ OR=3.950，95% CI为1.288~12.118）、流血开始孕周≥8周（ OR=4.909，95% CI为1.687~14.290）及流血持续时间为≥10 d（ OR=10.337，95% CI为3.595~29.725）均为流产的独立危险因素（ P均<0.05）。 结论:妊娠早期阴道流血开始孕周及持续时间与该类先兆流产孕妇发生难免流产密切相关，SCH可加重阴道流血症状，临床上应注重先兆流产孕妇的阴道流血事件的管理。

abstractsObjective:To investigate the relationship between characteristics of bleeding in the first trimester and pregnancy loss in women with threatened abortion.Methods:The clinical data of 240 threatened abortion women with bleeding as the main manifestation admitted to Women and Children′s Hospital of Chongqing Medical University from January 2019 to December 2022 were retrospectively analyzed. The pregnancy outcomes were followed up, and the effects of age, body mass index (BMI), history of adverse pregnancy and childbirth, pregnancy mode, number of pregnancy fetus, gestation at presentation, duration of bleeding, subchorionic hematoma (SCH) area and infection indicators on pregnancy outcomes were analyzed by grouping and stratification method. Univariate and multivariate logistic regression analysis were used to screen the high risk factors associated with miscarriage.Results:(1) General conditions: the age of 240 pregnant women with first-trimester bleeding was (30.6±4.5) years old. There were 105 cases of natural pregnancy and 135 cases of in vitro fertilization-embryo transfer (IVF-ET); 176 singleton pregnancies and 64 twin pregnancies; 59 without SCH and 181 with SCH. (2) Pregnancy outcome: the total miscarriage rate was 9.2% (22/240), and the live birth rate was 90.8% (218/240). Among the live birth pregnant women, 51.8% (113/218) had at least one pregnancy complications, and the rates of premature delivery, cesarean section and postpartum hemorrhage were 11.9% (26/218), 57.8% (126/218), and 1.8% (4/218), respectively. (3) Pregnancy outcomes in different groups: compared with the spontaneous pregnancy group, the pregnant women in the IVF-ET group were older, the onset of bleeding was earlier, and the rates of twin pregnancy and cesarean section were higher, but the duration of bleeding and SCH area were smaller, and the incidence of miscarriage were lower. Compared with the non-SCH group, the pregnant women in the SCH group were younger and the duration of bleeding was longer. The incidence of hypertensive disorder in pregnancy (HDP) was lower, and the differences were statistically significant (all P<0.05). (4) Univariate and multivariate logistic regression analysis results: the miscarriage rate of pregnant women with BMI ≥25 kg/m 2 was higher than that of pregnant women with BMI <25 kg/m 2 (17.1% vs 7.5%), the rate of spontaneous pregnancy was higher than that of IVF-ET (13.3% vs 5.9%), the rate of pregnant women with bleeding ≥8 weeks of gestation was higher than that of <8 weeks of gestation (14.7% vs 4.6%), the rate of pregnant women with bleeding duration ≥10 days was higher than that of <10 days (22.7% vs 4.0%), and the rate of pregnant women with infection was higher than that of pregnant women without infection (14.9% vs 5.5%). The differences were statistically significant (all P<0.05). BMI≥25 kg/m 2 ( OR=3.950, 95% CI: 1.288-12.118), bleeding onset at ≥8 weeks of gestation ( OR=4.909, 95% CI: 1.687-14.290) and bleeding duration ≥10 days ( OR=10.337, 95% CI: 3.595-29.725) were independent risk factors for miscarriage (all P<0.05). Conclusions:The onset and duration of first-trimester bleeding are closely related to pregnancy loss in threatened abortion patients, SCH could worsen the symptoms of bleeding. First-trimester bleeding events should be focused on such patients.