Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Loyola University Medical Center, Maywood, IL (Drs Dhillon, Holthaus, and Alrahmani).
Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Women's Health, University of Minnesota Medical Center, Minneapolis, MN (Dr Nashif).
Am J Obstet Gynecol MFM. 2023 Jul;5(7):100951. doi: 10.1016/j.ajogmf.2023.100951. Epub 2023 Apr 4.
Magnesium sulfate is used for seizure prophylaxis in preeclampsia and for fetal neuroprotection when delivery is anticipated before 32 weeks of gestation. Existing risk assessment tools for postpartum hemorrhage often identify the use of magnesium sulfate as an intrapartum risk factor. Previous studies examining the association between the use of magnesium sulfate and postpartum hemorrhage have relied largely on qualitative estimates of blood loss rather than quantitative estimates of blood loss.
This study aimed to determine whether intrapartum administration of magnesium sulfate is associated with an increased risk of postpartum hemorrhage using a quantitative blood loss assessment via the use of graduated drapes and weight differences in surgical supplies.
This case-control study was conducted to test the hypothesis that intrapartum parenteral administration of magnesium sulfate is not independently associated with postpartum hemorrhage. All deliveries at our tertiary-level academic medical center between July 2017 and June 2018 were reviewed. Of note, 2 categories of postpartum hemorrhage were defined: the traditional definition (>500 mL for vaginal delivery and >1000 mL for cesarean delivery) and the contemporary definition (>1000 mL regardless of delivery mode). Statistical analyses using the chi-square test, Fisher exact test, t test, or Wilcoxon rank-sum test were performed to compare the patients who did and did not receive magnesium sulfate concerning the rates of postpartum hemorrhage, pre- and postdelivery hemoglobin level, and rates of blood transfusion.
A total of 1318 deliveries were included, with postpartum hemorrhage rates of 12.2% (traditional definition) and 6.2% (contemporary definition). Multivariate logistic regression did not find the use of magnesium sulfate as an independent risk factor by either definition (odds ratio, 1.44 [95% confidence interval, 0.87-2.38] and 1.34 [95% confidence interval, 0.71-2.54]). The only significant independent risk factor was cesarean delivery, by both definitions (odds ratio, 2.71 [95% confidence interval, 1.85-3.98] and 19.34 [95% confidence interval, 8.55-43.72]).
In our study population, intrapartum administration of magnesium sulfate was not found to be an independent risk factor for postpartum hemorrhage. Cesarean delivery was determined as an independent risk factor, consistent with previous reports.
硫酸镁被用于子痫前期的惊厥预防以及预计在 32 周妊娠前分娩的胎儿神经保护。现有的产后出血风险评估工具通常将硫酸镁的使用视为分娩期的一个风险因素。之前研究使用硫酸镁与产后出血之间的关联，主要依赖于对出血量的定性估计，而非对出血量的定量估计。
本研究旨在通过使用带刻度的手术巾和手术用品的重量差异进行定量失血量评估，确定分娩期给予硫酸镁是否会增加产后出血的风险。
本病例对照研究旨在检验以下假设：分娩期给予硫酸镁不会增加产后出血的风险。对 2017 年 7 月至 2018 年 6 月在我们三级学术医疗中心进行的所有分娩进行了回顾性研究。需要注意的是，定义了两种产后出血类型：传统定义（阴道分娩>500 毫升，剖宫产>1000 毫升）和现代定义（无论分娩方式，出血量>1000 毫升）。使用卡方检验、Fisher 确切检验、t 检验或 Wilcoxon 秩和检验比较接受硫酸镁与未接受硫酸镁的患者之间的产后出血率、分娩前后血红蛋白水平以及输血率。
共纳入 1318 例分娩，产后出血率分别为传统定义的 12.2%（1318/10809）和现代定义的 6.2%（1318/21172）。多变量逻辑回归未发现硫酸镁的使用是任何一种定义下的独立危险因素（比值比，1.44[95%置信区间，0.87-2.38]和 1.34[95%置信区间，0.71-2.54]）。唯一显著的独立危险因素是剖宫产，两种定义均如此（比值比，2.71[95%置信区间，1.85-3.98]和 19.34[95%置信区间，8.55-43.72]）。
在我们的研究人群中，分娩期给予硫酸镁并未被发现是产后出血的独立危险因素。剖宫产被确定为独立危险因素，与之前的报告一致。
