孕前体重指数轻度偏低与新生儿出生结局关系的研究

Association between maternal pre-pregnancy body mass index and birth outcome

目的探讨孕前BMI轻度偏低与新生儿出生结局的关系。方法选取2017年9月至2018年9月在宁波市妇女儿童医院行首次产前检查的孕妇为研究对象,将研究对象分为孕前BMI轻度偏低组(18.5 kg/m^(2)≤BMI<19.8 kg/m^(2))和孕前BMI适宜组(19.8 kg/m^(2)≤BMI<24 kg/m^(2)),观察其在分娩时新生儿低出生体重、早产、小于胎龄儿(SGA)等的发生情况。采用多重线性回归分析孕前BMI轻度偏低与新生儿出生体重、头围、体重指数(PI)、身长、孕周的关系;采用多因素logistic回分析孕前BMI轻度偏低与新生儿低出生体重、早产和SGA的关联。结果共有1212例孕妇纳入本研究。调整年龄、学历、体重增重、孕次、子宫手术史和月经初潮年龄后,多重线性回归分析显示,孕前BMI轻度偏低与新生儿出生体重(β=-0.26,Z=-7.19,P<0.01)、PI(β=-0.21,Z=-8.65,P<0.01)、孕周(β=-0.65,Z=-5.86,P<0.01)均有关;多因素logistic回归分析显示,孕前BMI轻度偏低与与低出生体重(OR=2.59,95%CI:1.68~3.97,P<0.01)、早产(OR=2.68,95%CI:1.76~4.09,P<0.01)、SGA(OR=3.33,95%CI:2.03~5.48,P<0.01)均有关。结论孕前BMI轻度偏低与低出生体重、早产和SGA等多个出生结局有关,应值得进一步研究。

Objective To explore the relationship between maternal pre-pregnancy body mass index(BMI)and birth outcomes.Methods A total of 1212 pregnant women who had their first antenatal check-up at Ningbo Women and Children's Hospital from September 2017 to September 2018 were enrolled in the study.According to the BMI at first antenatal check-up the pregnant women were divided into low BMI group(18.5 kg/m^(2)≤BMI<19.8 kg/m^(2),n=264)and normal BMI group(19.8 kg/m^(2)≤BMI<24 kg/m^(2),n=948).The low birth weight of infants,premature delivery,small for gestational age(SGA)were compared between two groups.Multiple linear regression was used to analyze the relationship between midly low pre-pregnancy BMI and Multivariate logistic analysis was used to analyze the relationship between midly low pre-pregnancy BMI and low birth weight,premature delivery,SGA.Results After adjusting for age,education,weight gain,number of pregnancy,history of uterine surgery,and menarche,multiple linear regression showed that mildly low pre-pregnancy BMI was associated with newborn birth weight(β=-0.26,Z=-7.19,P<0.01),PI(β=-0.21,Z=-8.65,P<0.01)and gestational age(β=-0.65,Z=-5.86,P<0.01).Multivariate logistic regression showed that mildly low pre-pregnancy BMI was associated with low birth weight(OR=2.59,95%CI:1.68-3.97,P<0.01),premature delivery(OR=2.68,95%CI:1.76-4.09,P<0.01)and SGA(OR=3.33,95%CI:2.03-5.48,P<0.01).Conclusion Mildly low pre-pregnancy BMI is associated with low birth weight,premature delivery,and SGA.