Objective: To anlysis the efficacy and safety of cut-umbilical cord milking (C-UCM) compared with immediate cord clamping in preventing anemia and iron deficiency among term cesarean-delivered newborns. Methods: A total of 485 pregnant women planning to deliver by cesarean section were recruited in this randomized controlled trial in Hunan Maternal and Child Health Hospital and Liuyang Maternal and Child Health Care Hospital from July 2016 to April 2019. A block randomization was conducted to evenly allocate them to the controlled group and the C-UCM group. In the controlled group, the cord was clamped within 30 seconds as routine. In the C-UCM group, the cord was first clamped at 25 cm from the newborn's navel, and then the blood in the cord was gently squeezed into the newborn's body until the cord became white and shriveled. The cord was clamped twice at 2-3 cm from the newborn's navel subsequently. Neonatal jaundice, hyperbilirubinemia and polycythemia were monitored before discharge. After the newborns discharged, their hemoglobin, red blood cell count, hematocrit (at the age of 1, 6 and 12 months) and serum ferritin (at the age of 6 and 12 months) were followed up; body length and weight were measured; and information about their feeding and iron supplementation were collected (at the age of 1, 6, 12 and 18 months). The two groups were compared by t test, Mann-Whitney U test, χ² test, or Fisher exact probability method. The hospital was set as a random item, and the mixed effects regression model was used to evaluate the effect of C-UCM on relevant indicators of cesarean-delivered newborns. Results: There were 244 women in the C-UCM group with an average age of (31.9±4.4) years, and 241 in the control group with an average age of (31.8±4.2) years (P>0.05). There was no statistically significant difference between the C-UCM group and the control group at 1, 6 and 12 months of age in hemoglobin [(123.6±14.5) vs (122.2±14.5) g/L, (115.3±9.4) vs (114.1±8.5) g/L, (115.6±9.6) vs (116.1±12.6) g/L] or anemia incidence rate [15.2% (17/112) vs 18.4% (19/103), 22.7% (34/150) vs 26.8% (44/164), 22.3% (25/112) vs 19.5% (22/113)] (all P>0.05). There was no statistically significant difference between the two groups at 6 and 12 months of age in serum ferritin [M (Q1, Q3), 39.9 (24.9, 61.8) vs 43.6 (25.2, 100.9) μg/L, 40.3 (25.4, 259.2) vs 40.3 (26.4, 167.6) μg/L)] or iron deficiency incidence rate [6.1% (5/82) vs 4.2% (3/72), 6.7% (5/75) vs 3.8% (3/80)] (all P>0.05). There were also no significant difference between the two groups in other indicators, such as the Z-score of weight-for-length, the incidence of neonatal jaundice, and the incidence of neonatal hyperbilirubinemia (all P>0.05). After adjusting for the relevant covariates, there were still no significant effects of C-UCM on these outcomes above. Conclusions: Compared to immediate cord clamping, the intervention of gently squeezing 25 cm of the cord does not significantly reduce the risk of anemia or iron deficiency in term cesarean-delivered newborns, nor does it have a significant impact on infant growth and development. Yet this intervention does not increase the risk of jaundice or hyperbilirubinemia in newborns as well.
目的： 分析断脐后捋挤脐血（C-UCM）预防足月剖宫产儿贫血和铁缺乏的有效性和安全性。 方法： 本随机对照试验纳入2016年7月至2019年4月湖南省妇幼保健院和浏阳市妇幼保健院剖宫产孕妇485名，采用区组随机分组将其等比例分配至对照组和C-UCM组。对照组按照临床常规在30 s内完成结扎断脐，C-UCM组在距新生儿肚脐25 cm处行初次结扎断脐，而后轻柔捋挤该段脐带中的血液至新生儿体内、待脐带发白变瘪后再在距肚脐2~3 cm处行二次结扎断脐。新生儿出院前监测黄疸、高胆红素血症和红细胞增多症情况；出院后随访并检测血红蛋白、红细胞计数和红细胞压积（1、6和12月龄）和血清铁蛋白（6和12月龄），测量身长、体重，询问喂养和补铁情况（1、6、12和18月龄），并比较上述指标在两组间差异。将医院设为随机项，采用混合效应回归模型评价C-UCM对剖宫产儿相关指标的影响。 结果： 485名孕妇年龄为（31.8±4.3）岁；对照组241名，年龄为（31.8±4.2）岁，C-UCM组244名，年龄为（31.9±4.4）岁，两组年龄差异无统计学意义（P>0.05）。C-UCM组和对照组新生儿1、6和12月龄血红蛋白水平［（123.6±14.5）比（122.2±14.5）g/L、（115.3±9.4）比（114.1±8.5）g/L、（115.6±9.6）比（116.1±12.6）g/L］和贫血发生率［15.2%（17/112）比18.4%（19/103）、22.7%（34/150）比26.8%（44/164）、22.3%（25/112）比19.5%（22/113）］差异无统计学意义（均P>0.05）。C-UCM组和对照组6和12月龄血清铁蛋白水平［M（Q1，Q3）］［39.9（24.9，61.8）比43.6（25.2，100.9）μg/L，40.3（25.4，259.2）比40.3（26.4，167.6）μg/L］和铁缺乏发生率［6.1%（5/82）比4.2%（3/72）、6.7%（5/75）比3.8%（3/80）］差异均无统计学意义（均P>0.05）。两组间身长别体重Z评分、新生儿黄疸和新生儿高胆红素血症发生率等差异均无统计学意义（均P>0.05）。调整相关协变量后仍未见C-UCM对上述结局有影响（均P>0.05）。 结论： 与立即钳夹脐带相比，未见断脐后轻柔捋挤25 cm脐带血的干预方法降低足月剖宫产儿贫血和铁缺乏的发生风险，未见影响婴儿生长发育，但也未见其增加新生儿黄疸和高胆红素血症发生风险。.