Objective: To analyze the outcome of vaginal trial labor of pregnant women with low-lying placenta detected by translabial ultrasonography, and to explore the influencing factors of vaginal trial delivery and the risk factors of postpartum hemorrhage (PPH). Methods: A total of 80 pregnant women who were diagnosed by translabial ultrasonography with low-lying placenta and underwent vaginal trial delivery in Women's Hospital, School of Medicine Zhejiang University were collected. Based on the distance of placenta lower edge to cervical internal os (IOD) 1 cm, and the general characteristics and pregnancy outcomes of pregnant women with IOD≤1 cm and 1-2 cm were compared and the related factors of PPH were analyzed by binary logistic regression analysis. Results: Among the 80 pregnant women with low-lying placenta, 41 cases with IOD≤1 cm and 39 cases with IOD 1-2 cm, respectively. The rate of cesarean section in the two groups were 15% (6/41) and 15% (6/39), respectively. The birth weight of newborns were (3 334±360) and (3 460±365) g, respectively. PPH rates were 24% (10/41) and 26% (10/39), respectively, and the differences were not statistically significant (all P>0.05). Among the 80 pregnant women with low-lying placenta, 60 cases did not have PPH, and 20 cases did. The rates of placenta manual removal were 2% (1/60) and 20% (4/20), respectively. The birth weight of newborns were (3 330±368) and (3 591±284) g, respectively. The differences were statistically significant (all P<0.05). Binary logistic regression analysis suggested that placenta manual removal was a risk factor for PPH in pregnant women with low-lying placenta (OR=30.448, P=0.029). Conclusions: The results of vaginal trial labor in women with IOD≤1 cm and 1-2 cm are comparable, and vaginal trial labor could be attempted in those without contraindications of vaginal delivery. The main adverse complication of vaginal trial labor is PPH, and those with placenta manual removal need to make corresponding plans.
目的： 分析经会阴超声检查足月单胎低置胎盘孕妇阴道试产分娩结局，探讨低置胎盘孕妇阴道试产的影响因素及产后出血的高危因素。 方法： 收集2013年1月至2020年12月于浙江大学医学院附属妇产科医院住院分娩，经会阴超声检查确诊为低置胎盘并行阴道试产的足月单胎孕妇80例。以胎盘下缘据子宫颈内口距离（IOD）1 cm为界，分为IOD≤1 cm组和1~2 cm组，比较两组孕妇的妊娠结局，同时使用二元logistic回归分析探讨产后出血的相关因素。 结果： 80例低置胎盘孕妇中，IOD≤1 cm组41例，1~2 cm组39例，两组孕妇的中转剖宫产率分别为15%（6/41）和15%（6/39），新生儿出生体重分别为（3 334±360）和（3 460±365）g，产后出血率分别为24%（10/41）和26%（10/39），分别比较，差异均无统计学意义（P均>0.05）。80例低置胎盘孕妇中，未发生产后出血60例，发生产后出血20例，胎盘人工剥离率分别为2%（1/60）和20%（4/20），新生儿出生体重分别为（3 330±368）和（3 591±284）g，分别比较，差异均有统计学意义（P均<0.05）。二元logistic回归分析显示，胎盘人工剥离是低置胎盘孕妇发生产后出血的危险因素（OR=30.448，P=0.029）。 结论： IOD≤1 cm与1~2 cm低置胎盘孕妇的阴道试产结局相当，排除禁忌均可尝试阴道试产。阴道试产的主要不良并发症为产后出血，胎盘人工剥离者需做好相应预案。.