Clinical Epidemiology Division, Department of Medicine, Karolinska Institutet, Solna, Stockholm, Sweden.
Department of Women's Health, Division of Obstetrics, Karolinska University Hospital, Stockholm, Sweden.
Sci Rep. 2024 Sep 27;14(1):22152. doi: 10.1038/s41598-024-72963-2.
With increasing rates of postpartum hemorrhage (PPH) in high-income countries, an important clinical concern is the impact of labor duration on the risk of PPH. This study examined the relationship between increasing active first stage labor duration and PPH and explored the role of second stage labor duration and cesarean delivery (CD) in this association. Including 77,690 nulliparous women with spontaneous labor onset, first stage labor duration was defined as the time from 5 cm to 10 cm, second stage duration from 10 cm dilation to birth and PPH as estimated blood loss > 1000 ml. Using modified Poisson regression for risk ratios (RR) and confidence intervals (CI), we found a 1.5-fold (RR, 1.53; 95% CI, 1.41‒1.66) increased PPH risk when first stage of labor exceeded 12.1 h compared to the reference (< 7.7 h). Mediation analysis showed that 18.5% (95% CI, 9.7‒29.6) of the increased PPH risk with a prolonged first stage (≥ 7.7 h) was due to a prolonged second stage (> 3 h) or CD. These results suggest that including first stage duration in intrapartum assessments could improve PPH risk identification in first-time mothers with a singleton fetus in vertex presentation at full term with spontaneous labor onset.
随着高收入国家产后出血 (PPH) 率的上升，一个重要的临床关注点是产程持续时间对 PPH 风险的影响。本研究探讨了活跃的第一产程持续时间增加与 PPH 的关系，并探讨了第二产程持续时间和剖宫产 (CD) 在这种关联中的作用。该研究纳入了 77690 名自发性临产的初产妇，第一产程持续时间定义为从 5cm 到 10cm，第二产程持续时间从 10cm 扩张到分娩，PPH 定义为估计出血量 > 1000ml。使用校正后的泊松回归分析风险比 (RR) 和置信区间 (CI)，我们发现与参考值 (<7.7h) 相比，第一产程持续时间超过 12.1h 时，PPH 风险增加了 1.5 倍 (RR，1.53；95% CI，1.41-1.66)。中介分析显示，第一产程持续时间延长（≥7.7h）导致 PPH 风险增加 18.5%（95% CI，9.7-29.6），这归因于第二产程延长（>3h）或 CD。这些结果表明，在第一产程评估中纳入第一产程持续时间，可能会提高足月、自发性临产、头位初产妇的 PPH 风险识别能力。
