孕前体重指数和孕期增重对妊娠结局的影响

Impact of gestational weight gain and pre-pregnant body mass index on pregnant outcomes

目的探讨孕前体重指数（body mass index，BMI）和孕期增重对妊娠结局的影响，为制定孕期体重分级管理方案提供依据。方法研究对象为2009年1月至2010年4月在南京大学医学院附属鼓楼医院产科定期产前检查的健康单胎妊娠孕妇2409例。根据孕前BMI分为孕前体重过低（BMI〈18．5）、体重正常（BMI18．5～）、超重和肥胖（BMI≥24．0）3组。孕期增重计算方法为分娩前最高体重减去孕前体重。将孕前体重过低和体重正常的孕产妇，分别按孕期增重〈10kg、10kg～、≥15妇分为3个亚组；孕前超重和肥胖的孕产妇，按孕期增重〈5kg、5k～、10kg～、≥15kg分为4个亚组。记录分娩孕周、分娩方式、新生儿出生体重和Apgar评分，以及妊娠期高血压疾病、妊娠期糖尿病、巨大儿、胎儿生长受限及早产的发生率。统计学分析采用t检验、方差分析、Student Newman—Keuls检验、χ2检验或Fisher精确概率法。结果（1）2409例孕妇中，孕前体重过低、体重正常、超重和肥胖组的构成比分别为18．5％（445例）、69．9％（1685例）和11．6％（279例）。孕前超重和肥胖组HDP、GDM和巨大儿发生率、剖宫产率分别为12．9％．（36例）、17．9Voo（50例）、13．6％（38例）和52．3％（146例），均高于孕前体重过低组[3．4％（15例）、4．3％（19例）、3．8Voo（17例）和25．8％（1t5例），χ2分别为23．8、37．1、23．5和50．2，P〈0．05]和体重正常组[5．5％（92例）、7．8％（132例）、7．8％（132例）和31．6％（532例），15。分别为21．8、29．0、10．1和3．4，P％0．05]。（2）孕前体重正常者，孕期增重〈10kg亚组FGR发生率和早产率分别为3．5％（4／115）和8．7％（10／115），高于增重10kg～亚组[0．7％（4／548）和3．3％（18／548），χ2分别为6．0和6．9，P％0．05]和≥15kg亚组[0．8％（8／1022）和3．6％（37／1022），χ2分别为7．2和6．7，P〈0．05]。增重≥15kg亚组巨大儿发生率和剖宫产率分别为10．7％（109／1022）和34．5％（353／1022），高于增重〈10kg亚组[3．5％（4／115）和32．2％（37／115），15。分别为6．0和63．0，P〈0．05]和10kg～亚组[3．5％（19／548）和25．9％（142／548），χ2分别为24．7和31．0，P％0．053。（3）孕前超重和肥胖者，孕期增重不同的4个亚组妊娠并发症和妊娠结局比较，差异均无统计学意义（P〉0．05）。结论孕前超重或肥胖者妊娠并发症和剖宫产的风险增加。孕前体重正常者如果孕期增重过高或过低，也可能增加妊娠并发症风险，孕期增重控制在10～15kg较为适宜。

Objective To evaluate the effects of gestationa; weight gain（GWG） in different pre- pregnant body mass index （BMI） women on perinatal outcomes and to provide evidences for gestational weight management protocol. Methods Totally, 2409 healthy singleton pregnant women accepted regular prenatal examinations in Nanjing Drum Tower Hospital from January 2009 to April 2010 were recruited in this study. They were divided into three groups according to pre-pregnant BMI, which were low BMI group （BMI〈18.5）, normal BMI group （BMI 18.5-） and high BMI group （BMI≥24.0）. According to GWG, the difference between pre-delivery maximal weight and pre pregnant weight, the low and normal BM1 women were divided into 〈10 kg, 10 kg and ≥15 kg GW（; subgroups, and the high BMI women were divided into 〈5 kg, 5 kg-, 10 kg- and ≥15 kg GWG subgroups. Data including gestational age, delivery mode, newborns＇ birth weight, Apgar score and incidences of gestational complications, such as hypertensive disorders complicating pregnancy （HI）P）, gestational diabetes mellitus （GDM）, macrosomia, fetal growth restriction （FGR） and preterm birth, were recorded. Analysis of variance, Student-Newman Keuls, C/H square test and Fisher exact lest were applied for statistics. Results （1） Among the 2409 women, the percentages of low, normal and high BMI groups were 18.5% （n 445）, 69.9% （n=1685） and 11.6% （n= 279）, respectively. The incidences of HDP, GI）M, macrosomia and caesarean delivery in high BM1 group were 12.9% （n=36）, 17.9% （n=50）, 13.6% （n=38） and 52.3% （n=146）, respectively, higher than those in low BM1 group [3.4% （n=lh）, 4.3% （n=19）, 3.8% （n 17） and 25.8% （n=115）, χ2 =23.8, 37. 1, 23.5 and 50.2, P〈0.05% and those in normal BMI group [5.5% （n 92）, 7.8% （n=132）, 7.8% （n=132） and31.6% （n=532）,）%% 21.8, 29.0, 10.1 and 3.4, P〈 0. 05]. （2） In normal BMI group, the rates of F（;R and preterm birth in GWG 〈%10 kg subgroup were 3.5% （4/115） and 8.7% （10/115）, higher than those in GWG 10 kg subgroup [0.7%（4/548） and 3. 3%（18/548）, χ2=6.0 and 6.9, P〈0.05] and GWG ≥15 kg subgroup [（0.8% （8/1022） and 3.6% （37/1022）, χ2=7.2 and 6.7, P〈0.05]. The rates of macrosomia and cesarean delivery in GWG ≥15 kg subgroup were 10.7% （109/1022） and 34.5% （353/1022）, higher than those in C-WG%10 kg subgroup [3.5% （4/115） and 32.2% （37/115）,χ2= 6.0 and 63.0, P〈0.05% and GWG 10 kg subgroup [3.5% （19/548） and 25.9% （142/548）, χ2=24.7 and 31.0, P〈0.05%. （3） In high BMI group, the incidences of all pregnancy complications and perinatal outcomes did not show statistical significance among the four GWG subgroups （P〉0. 05）. Conclusions High pre pregnant BMIisa high risk factor of pregnancy complications. It is suggested that normalBMI women should control GWG at 10-15 kg to lower the incidences of pregnancy complications.