妊娠中期胎盘前置状态缓解孕妇的围产结局分析

Analysis of perinatal outcomes in pregnant women with the resolution of placenta previa in the second trimester

目的探讨妊娠中期胎盘前置状态缓解孕妇的围产结局。方法本研究为回顾性队列研究, 纳入2019年1月1日至2020年12月31日于北京大学第三医院行产前检查并分娩的单胎妊娠孕妇, 将妊娠20~24周超声诊断胎盘前置状态且在分娩前胎盘位置恢复正常的孕妇403例纳入为研究组, 并1∶1匹配胎盘位置始终正常的孕妇403例为对照组。主要结局为产后出血率, 次要结局包括产后出血量、严重出血并发症、输血、药物应用、器械或手术止血措施应用、分娩孕周以及新生儿相关结局。通过单因素及多因素logistic回归方法分析围产结局。结果 (1)与对照组比较, 研究组孕妇的产后出血发生率[分别为10.4%(42/403)、17.6%(71/403)]、产后出血量(中位数分别为375、400 ml)、产后出血量≥500 ml的比例[分别为18.6%(75/403)、30.5%(123/403)]、器械或手术止血措施的应用比例[分别为1.7%(7/403)、4.5%(18/403)]均升高, 分别比较, 差异均有统计学意义(P均<0.05)。两组的新生儿结局, 包括新生儿出生体重、小于胎龄儿、入住新生儿重症监护病房、新生儿窒息的发生率分别比较, 差异均无统计学意义(P均>0.05)。(2)研究组阴道分娩孕妇的产后出血率[分别为31.7%(66/208)、17.5%(39/223)]、产后出血量(中位数分别为390、380 ml)、器械或手术止血措施的比例[分别为3.8%(8/208)、0.4%(1/223)]均高于对照组阴道分娩孕妇, 分别比较, 差异均有统计学意义(P均<0.05)。研究组与对照组剖宫产术分娩孕妇的产后出血率比较, 差异无统计学意义(P=0.545), 但研究组与对照组产后出血量≥500 ml的比例分别为29.2%(57/195)、20.0%(36/180), 差异有统计学意义(P=0.039)。(3)多因素分析结果显示, 与对照组相比, 研究组孕妇的产后出血风险(aOR=2.042, 95%CI为1.313~3.175)、药物应用(aOR=1.684, 95%CI为1.142~2.484)及器械或手术止血措施应用(aOR=2.696, 95%CI为1.089~6.675)均显著增加(P均<0.05)。研究组阴道分娩孕妇的产后出血风险为对照组相应者的2.021倍(95%CI为1.269~3.220;P=0.003)。结论妊娠中期胎盘前置状态的孕妇, 即使分娩前胎盘位置恢复正常, 仍是产后出血的高危因素, 尤其是阴道分娩时应特别予以关注和警惕。

Objective:To investigate perinatal outcomes of pregnant women with the resolution of placenta previa in the second trimester.Methods:This study was a retrospective cohort study,which included singleton pregnant women who received prenatal care and delivered at Peking University Third Hospital from January 1st 2019 to December 31st 2020.A total of 403 pregnant women diagnosed with placenta previa by ultrasound at 20-24 weeks of gestation and the placental position returned to normal before delivery were included in the study group,and 403 pregnant women with normal placental position matched 1∶1 were the control group.The primary outcome was postpartum hemorrhage rate,and secondary outcomes included postpartum bleeding volume,severe hemorrhage complications,blood transfusion,drug application,the application of instrument or surgical hemostasis measures,gestational week of delivery,and neonatal outcomes.The perinatal outcomes were analyzed by univariate and multivariate logistic regression methods.Results:(1)Compared with the control group,the incidence of postpartum hemorrhage[10.4%(42/403)vs 17.6%(71/403)],postpartum hemorrhage volume(median:375 vs 400 ml),the proportion of postpartum hemorrhage≥500 ml[18.6%(75/403)vs 30.5%(123/403)],and the proportion of application of instrument or surgical hemostasis measures[1.7%(7/403)vs 4.5%(18/403)]in the study group were increased,and the differences were statistically significant(all P<0.05).Neonatal outcomes,including birth weight,small for gestational age,hospitalization in neonatal intensive care unit and incidence of neonatal asphyxia,were compared between the two groups,and there were no statistically significant differences(all P>0.05).(2)In pregnant women with vaginal delivery,the postpartum hemorrhage rate[31.7%(66/208)vs 17.5%(39/223)],postpartum hemorrhage volume(median:390 vs 380 ml),the proportion of instrument or surgical hemostasis measures[3.8%(8/208)vs 0.4%(1/223)]of the study group were higher than those of the control group,and the differences were statistically significant(all P<0.05).There was no significant difference in the rate of postpartum hemorrhage between the study group and the control group who gave birth by cesarean setion(P=0.545),but the proportion of postpartum hemorrhage≥500 ml in the study group and the control group were 29.2%(57/195)and 20.0%(36/180),and the difference was statistically significant(P=0.039).(3)The results of multivariate analysis showed that compared with the control group,the risk of postpartum hemorrhage(a OR=2.042,95%CI:1.313-3.175),the application of drugs(a OR=1.684,95%CI:1.142-2.484)and the application of instruments or surgical hemostasis measures(a OR=2.696,95%CI:1.089-6.675)were significantly increased in the study group(all P<0.05).Among women who delivered vaginally,the risk of postpartum hemorrhage in the study group was 2.021 times greater than that in the control group(95%CI:1.269-3.220;P=0.003).Conclusion:In women with placental previa in the second trimester of pregnancy,even if the placental position returns to normal before delivery,it is still a high risk factor for postpartum hemorrhage,especially in vaginal delivery.