孕前体重指数、孕期体重增加与新生儿窒息的关系

目的 了解孕前体重指数(BMI)、孕期体重增加与新生儿窒息发生危险的关系.方法 数据来自"中美预防出生缺陷和残疾合作项目"中嘉兴地区的围产保健监测数据库.研究对象为1995-2000年在嘉兴地区参加婚前/孕前体检且分娩单胎活产儿孕满20周的83 030名孕产妇.运用χ2检验或趋势χ2检验比较不同BMI组或其他特征人群新生儿窒息发病率的差别,利用多元logistic回归分析孕前BMI、孕期体重增加与新生儿窒息发生危险之间的关系.结果 新生儿窒息发病率为11.3%(95% CI:11.1%～11.6%).新生儿窒息发病率从BMI＜18.5 kg/m2组的11.0%(95% CI:10.5%～11.5%)逐渐升至BMI≥25.0 kg/m2组的12.9%(95% CI:11.6%～14.4%),自孕期体重增加＜0.3 kg/wk的12.4%(95% CI:11.9%～13.0%)逐渐降至≥0.5 kg/wk的10.6%(95% CI:10.1%～11.0%).孕前BMI≥25.0 kg/m2组的新生儿重度窒息发生率高于BMI更低组.在调整了地区、年龄、文化程度、职业、产次、产前检查次数、孕期高危因素、产时高危因素、孕周和出生体重后,以BMI＜18.5 kg/m2组为参照组,BMI为18.5～22.9 kg/m2、23.0～24.9 kg/m2和≥25.0 kg/m2组发生新生儿窒息的OR值分别为1.03(95% CI:0.97～1.09)、1.06(95% CI:0.96～1.16)和1.14(95% CI:1.00～1.31).进一步调整孕期增重后,上述OR值分别为1.02(95% CI:0.95～1.09)、1.01(95% CI:0.90～1.13)和1.08(95% CI:0.92～1.28).以孕期体重增加≥0.5 kg/wk组作为参照,孕期体重增加为0.3～kg/wk和＜0.3 kg/wk组发生新生儿窒息的OR值分别为1.06(95% CI:1.01～1.12)和1.09(95% CI:1.02～1.20).结论 孕期体重增加＜0.5 kg/wk加大新生儿窒息发生的危险,提示临床上宜对妇女孕前的BMI进行监测,并据此进行孕前指导和孕期管理,以保持合理的孕期体重,降低新生儿窒息的发生危险.

Relations between pre-pregnancy body mass index,gestational weightgain, and the occurrence of neonatalasphyxia

Objective To assess the relationship between pre-pregnancy body mass index(BMI),weight gain during pregnancy,and the risk of neonatal asphyxia.Methods Data was collected in 6 counties/cities covered by Peri-natal Health Care Surveillance System which was part of a Sino-American cooperative project on neural tube defects prevention established in 1992.The study population consisted of 83 030 women who attended premarital/preconception medical physical examination program and had delivered single live birth with at least 20 gestational weeks from 1995 to 2000 in Jiaxing area,Zhejiang province.Results from the Chi-square test were employed to test the differences in the rates of neonatal asphyxia between groups with different BMI and other characteristics.Multivariate logistic regression method was conducted to examine the association between pre-pregnancy BMI,gestational weight gain,and the risk of asphyxia.Results The average rate of neonatal asphyxia was 11.3%(95% CI:11.1%-11.6%).The rates of neonatal asphyxia among women with BMI＜18.5 kg/m2,18.5-22.9 kg/m2,23.0-24.9 kg/m2,and≥25.0 kg/m2 were 11.0%(95% CI:10.5%-11.5%),11.3%(95% CI:11.1%-11.6%),11.8%(95% CI:11.0%-12.6%),and 12.9%(95% CI:11.6%-14.4%)respectively.The rates of neonatal asphyxia were 12.4% among women with weight gain＜0.3 kg/wk.higher than women with higher weight gain.After adjusting for residencial area,maternal age,educational level,occupation,parity,times of prenatal visit,high-risk experiences during pregnancy,high-risk experiences at time of delivery,gestational week and birth weight,the estimated ORs were 1.03(95% CI:0.97-1.09),1.06(95% CI:0.96-1.16)and 1.14(95% CI:1.00-1.31),respectively.These ORs became 1.02(95% CI:0.95-1.09),1.01(95% CI:0.90-1.13)and 1.08(95% CI:0.92-1.28)after further adjusting the variable "gestational weight gain".The estimated ORs for neonatal asphyxia were 1.06(95% CI:1.01-1.12)for women with weight gain at 0.3-kg/wk and 1.09(95% CI:1.02-1.20)for women with weight gain＜0.3 kg/wk when compared to those with weight gain≥0.5 kg/wk.Conclusion Lower weight gain seemed to have the effect of increasing the risk of neonatal asphyxia.