Division of Maternal-Fetal Medicine, Department of Obstetrics & Gynecology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina 27599-7516, USA.
Am J Perinatol. 2011 Oct;28(9):735-9. doi: 10.1055/s-0031-1280853. Epub 2011 Jun 9.
We identify characteristics that predict resolution of placenta previa and develop a clinical model for likelihood of resolution. We conducted a retrospective study of 366 singleton pregnancies complicated by placenta previa diagnosed with resolution of the previa as the primary outcome. Regression analyses were performed to determine variables associated with resolution and optimal timing for repeat sonographic evaluation. A likelihood of resolution model was created using a parametric survival model with Weibull hazard function. Of the 366 cases, 84% of complete placentae previae and 98% of marginal placentae previae resolved at a mean gestational age of 28.6 ± 5.3 weeks. Only gestational age and distance from the internal cervical os at the time of diagnosis were significantly associated with resolution ( P < 0.01). Likelihood of resolution was not significantly associated with any other variables. Marginal previae diagnosed in the second trimester do not appear to warrant repeat ultrasound evaluation for resolution.
我们确定了预测胎盘前置胎盘消退的特征，并为其消退的可能性开发了一种临床模型。我们对 366 例由胎盘前置诊断的单胎妊娠进行了回顾性研究，以胎盘前置的消退为主要结局。回归分析用于确定与消退相关的变量和重复超声评估的最佳时机。使用具有 Weibull 风险函数的参数生存模型创建了消退可能性模型。在 366 例中，84%的完全性胎盘前置和 98%的边缘性胎盘前置在平均妊娠 28.6±5.3 周时消退。只有诊断时的孕龄和距宫颈内口的距离与消退显著相关（P<0.01）。消退的可能性与其他任何变量均无显著相关性。在孕中期诊断的边缘性前置胎盘似乎不需要重复超声检查以确定其是否消退。
