Abstract: Objective　To investigate the effects of vitamin D supplementation in the third trimester of pregnancy on maternal and neonatal 25 hydroxyvitamin D [25(OH)D] levels, neonatal physical development, and neonatal diseases. Methods　The pregnant women who delivered in Zhongshan Hospital Xiamen University and The First Affiliated Hospital of Xiamen University from January 2019 to December 2021 and their neonates were collected as research objects and were randomly divided into an intervention group (316 cases) and a control group (337 cases). In the intervention group, 269 cases were <35 years old and 47 cases were ≥35 years old; in the control group, 283 cases were <35 years old and 54 cases were ≥35 years old. The intervention group received daily vitamin D supplementation ≥600 IU from 28 weeks of gestation to delivery, and the control group received daily vitamin D supplementation <600 IU. The maternal antepartum and neonatal 25(OH)D levels were detected, the neonatal body weight, length, and head circumference were measured, and the delivery mode, premature delivery rate, and incidence of neonatal diseases were counted. Independent sample t test and χ² test were used. Results　The maternal antepartum and neonatal 25(OH)D levels in the intervention group were significantly higher than those in the control group [(27.91±7.56) μg/L vs. (24.65±6.83) μg/L, (16.24±4.31) μg/L vs. (12.60±3.97) μg/L], with statistically significant differences (both P<0.001). The maternal antepartum and neonatal vitamin D deficiency rates in the intervention group were significantly lower than those in the control group [19.62% (62/316) vs. 47.18% (159/337), 17.09% (54/316) vs. 49.26% (166/337)], with statistically significant differences (both P<0.001). The neonatal body weight, length, and head circumference in the intervention group were significantly higher than those in the control group (all P<0.05). The incidences of neonatal early-onset sepsis and neonatal necrotizing enterocolitis in the intervention group were significantly lower than those in the control group [1.27% (4/316) vs. 4.15% (14/337), 2.53% (8/316) vs. 6.23% (21/337)], with statistically significant differences (both P<0.05). There were no statistically significant differences in the cesarean section rate and premature delivery rate between the two groups (both P>0.05). Conclusion　Daily vitamin D supplementation ≥600 IU in the third trimester of pregnancy can increase the maternal and neonatal serum 25(OH)D levels, promote the neonatal physical development, and reduce the incidence of severe neonatal diseases, but has no significant effects on the cesarean section rate and premature delivery rate.

Key words: Vitamin D, 25 hydroxyvitamin D, Physical development, Neonatal diseases

摘要： 目的　探讨孕晚期补充维生素D对母儿25羟维生素D［25（OH）D］水平、新生儿体格发育及新生儿疾病的影响。方法　收集2019年1月至2021年12月在厦门大学附属中山医院及厦门大学附属第一医院定期产检并分娩的孕产妇及新生儿作为研究对象，随机分为干预组（316例）和对照组（337例）。干预组<35岁269例，≥35岁47例；对照组<35岁283例，≥35岁54例。干预组自妊娠28周至分娩每日补充维生素D≥600 IU，对照组每日补充维生素D <600 IU。检测孕产妇分娩前及新生儿25（OH）D水平，测量新生儿体质量、身长、头围，统计分娩方式、早产比例及新生儿疾病的发生率。行独立样本t检验、χ²检验。结果　干预组孕产妇分娩前及新生儿25（OH）D水平分别为（27.91±7.56）μg/L、（16.24±4.31）μg/L，均高于对照组（24.65±6.83）μg/L、（12.60±3.97）μg/L，差异均有统计学意义（均P<0.001）；干预组孕产妇分娩前及新生儿出生后维生素D缺乏率分别为19.62%（62/316）、17.09%（54/316），均低于对照组47.18%（159/337）、49.26%（166/337），差异均有统计学意义（均P<0.001）。干预组新生儿出生体质量、身长、头围均高于对照组（均P<0.05）；干预组新生儿早发型败血症、新生儿坏死性小肠结肠炎的发生率分别为1.27%（4/316）、2.53%（8/316），均低于对照组4.15%（14/337）、6.23%（21/337），差异均有统计学意义（均P<0.05）；两组孕产妇剖宫产率及早产率差异均无统计学意义（均P>0.05）。结论　孕晚期每日补充维生素D≥600 IU可以提高孕产妇及新生儿血清25（OH）D水平、促进新生儿体格发育并降低新生儿期重症疾病的发生率，但对孕产妇剖宫产率及早产的发生率不产生影响。

关键词: 维生素D, 25羟维生素D, 体格发育, 新生儿疾病