Department of Obstetrics, University Hospital Zurich, Frauenklinikstrasse 10, 8091, Zurich, Switzerland.
University of Zurich, Zurich, Switzerland.
Arch Gynecol Obstet. 2021 Oct;304(4):903-911. doi: 10.1007/s00404-021-06027-5. Epub 2021 Mar 20.
Postpartum hemorrhage is the major cause of maternal mortality worldwide. Retained placenta accounts for nearly 20% of severe cases. We investigated the influence of the time factor and retained placenta etiology on postpartum hemorrhage dynamics.
Our retrospective study analyzed a single-center cohort of 296 women with retained placenta. Blood loss was measured using a validated and accurate technique based on calibrated blood collection bags, backed by the post- vs pre-partum decrease in hemoglobin. We evaluated the relationship between these two blood loss parameters and the duration of the third stage of labor using Spearman rank correlation, followed by subgroup analysis stratified by third stage duration and retained placenta etiology.
Correlation analysis revealed no association between third stage duration and measured blood loss or decrease in hemoglobin. A shorter third stage (< 60 min) was associated with significantly increased uterine atony (p = 0.001) and need for blood transfusion (p = 0.006). Uterine atony was significantly associated with greater decrease in hemoglobin (p < 0.001), higher measured blood loss (p < 0.001), postpartum hemorrhage (p = 0.048), and need for blood transfusion (p < 0.001).
Postpartum blood loss does not correlate with third stage duration in women with retained placenta. Our results suggest that there is neither a safe time window preceding postpartum hemorrhage, nor justification for an early cut-off for manual removal of the placenta. The prompt detection of uterine atony and immediate prerequisites for manual removal of the placenta are key factors in the management of postpartum hemorrhage.
产后出血是全球孕产妇死亡的主要原因。胎盘滞留占严重病例的近 20%。我们研究了时间因素和胎盘滞留病因对产后出血动态的影响。
我们的回顾性研究分析了 296 例胎盘滞留的单中心队列。采用一种经过验证和准确的技术，根据校准的采血袋测量失血量，该技术基于产后血红蛋白下降与产前血红蛋白下降的差值。我们使用 Spearman 秩相关分析评估了这两个失血量参数与第三产程时间的关系，然后根据第三产程时间和胎盘滞留病因进行亚组分析。
相关性分析显示第三产程时间与测量失血量或血红蛋白下降之间没有关联。第三产程较短（<60 分钟）与明显增加的子宫收缩乏力（p=0.001）和输血需求（p=0.006）相关。子宫收缩乏力与血红蛋白下降明显相关（p<0.001）、测量失血量增加（p<0.001）、产后出血（p=0.048）和输血需求（p<0.001）。
在胎盘滞留的妇女中，产后失血与第三产程时间无关。我们的结果表明，在产后出血之前没有安全的时间窗口，也没有理由对胎盘的人工移除设定早期截止时间。及时发现子宫收缩乏力并立即准备好进行胎盘的人工移除是处理产后出血的关键因素。
