美国哥伦比亚大学欧文医学中心Cynthia Gyamfi-Bannerman小组取得一项新突破。他们的研究分析了延迟与即刻脐带结扎对剖宫产产妇失血的影响。2019年11月19日，国际知名学术期刊《美国医学会杂志》发表了这一成果。

美国妇产科学会建议足月新生儿出生后至少延迟30-60秒再行脐带结扎。大多数支持这种做法的文献来自于低风险的阴道分娩，而针对剖宫产的数据很少。

2017年10月至2018年2月，研究组在纽约市的两家医院进行了一项随机、临床试验，共招募了113名欲行剖宫产的单胎足月妇女，平均年龄为32.6岁。将其随机分组，其中56名行即刻脐带结扎，即在婴儿出生后15秒内结扎（即刻组），57名行延迟脐带结扎，即在婴儿出生60秒后再行结扎（延迟组）。

延迟组术前的平均血红蛋白水平为12.0 g/L，即刻组为11.6 g/L。延迟组术后第一天平均血红蛋白水平为10.1 g/L，即刻组为9.8 g/L，与术前相比差异均不显著。延迟组新生儿的平均血红蛋白水平为18.1 g/L，显著高于即刻组（16.4 g/L）。两组中各有1例非计划子宫切除。

总之，足月单胎妊娠剖宫产术后第一天，延迟脐带结扎与即刻脐带结扎相比，孕妇的血红蛋白水平并无显著差异。

附：英文原文

Title: Effect of Delayed vs Immediate Umbilical Cord Clamping on Maternal Blood Loss in Term Cesarean Delivery: A Randomized Clinical Trial

Author: Stephanie E. Purisch, Cande V. Ananth, Brittany Arditi, Logan Mauney, Barouyr Ajemian, Amy Heiderich, Tina Leone, Cynthia Gyamfi-Bannerman

Issue&Volume: 2019/11/19

Abstract:

Importance  The American College of Obstetricians and Gynecologists recommends a delay in umbilical cord clamping in term neonates for at least 30 to 60 seconds after birth. Most literature supporting this practice is from low-risk vaginal deliveries. There are no published data specific to cesarean delivery.

Objective  To compare maternal blood loss with immediate cord clamping vs delayed cord clamping in scheduled cesarean deliveries at term (≥37 weeks).

Design, Setting, and Participants  Randomized clinical trial performed at 2 hospitals within a tertiary academic medical center in New York City from October 2017 to February 2018 (follow-up completed March 15, 2018). A total of 113 women undergoing scheduled cesarean delivery of term singleton gestations were included.

Interventions  In the immediate cord clamping group (n = 56), cord clamping was within 15 seconds after birth. In the delayed cord clamping group (n = 57), cord clamping was at 60 seconds after birth.

Main Outcomes and Measures  The primary outcome was change in maternal hemoglobin level from preoperative to postoperative day 1, which was used as a proxy for maternal blood loss. Secondary outcomes included neonatal hemoglobin level at 24 to 72 hours of life.

Results  All of the 113 women who were randomized (mean [SD] age, 32.6 [5.2] years) completed the trial. The mean preoperative hemoglobin level was 12.0 g/dL in the delayed and 11.6 g/dL in the immediate cord clamping group. The mean postoperative day 1 hemoglobin level was 10.1 g/dL in the delayed group and 9.8 g/dL in the immediate group. There was no significant difference in the primary outcome, with a mean hemoglobin change of −1.90 g/dL (95% CI, −2.14 to −1.66) and −1.78 g/dL (95% CI, −2.03 to −1.54) in the delayed and immediate cord clamping groups, respectively (mean difference, 0.12 g/dL [95% CI, −0.22 to 0.46]; P = .49). Of 19 prespecified secondary outcomes analyzed, 15 showed no significant difference. The mean neonatal hemoglobin level, available for 90 neonates (79.6%), was significantly higher with delayed (18.1 g/dL [95% CI, 17.4 to 18.8]) compared with immediate (16.4 g/dL [95% CI, 15.9 to 17.0]) cord clamping (mean difference, 1.67 g/dL [95% CI, 0.75 to 2.59]; P < .001). There was 1 unplanned hysterectomy in each group.

Conclusions and Relevance  Among women undergoing scheduled cesarean delivery of term singleton pregnancies, delayed umbilical cord clamping, compared with immediate cord clamping, resulted in no significant difference in the change in maternal hemoglobin level at postoperative day 1.

DOI: 10.1001/jama.2019.15995

Source: https://jamanetwork.com/journals/jama/article-abstract/2755613