[Study on the distribution and related factors of birth weight of live births in Guangxi Zhuang Autonomous Region of China from 2016 to 2018].

Objective: To investigate the distribution and related factors of birth weight of live births and full-term infants in Guangxi Zhuang Autonomous Region of China. Methods: Based on Guangxi women and children information system from 2016 to 2018, a large real-time database about maternal and live-birth information was established. It covered 1 712 midwifery institutions in Guangxi. A total of 2 394 240 cases of live births were collected and 2 243 129 cases of which were full-term infants. The multivariate logistic regression model was used to analyze the related factors of low birth weight. Results: The birth weight of 2 394 240 live births, (3 123.49±461.08) g, in Guangxi was approximately normal distribution with a peak distribution to the left. The incidence of low birth weight was 8.05%, and the incidence of macrosomia was 2.07%. The incidence of low birth weight was 10.92% for the puerpera with body mass index (BMI, kg/m(2)) <18.5, 16.82% for the puerpera with height <145 cm, 8.92% for the puerpera with age <20 years old, 7.67% for the puerpera with age ≥35 years old, and 54.65% for the puerpera with premature birth. The birth weight of 2 243 129 full-term infants, (3 176.01±400.78) g, was approximately normal distribution with a peak distribution to the right. The incidence of low birth weight was 2.97%, and the incidence of macrosomia was 2.19%. The incidence of low birth weight was 4.73% for puerpera with BMI<18.5, 8.17% for puerpera with height<145 cm, 4.83% for puerpera with age <20 years old, and 3.05% for puerpera with age ≥35 years old. The risks of low birth weight [OR (95%CI) value] of pregnant women aged <20, 25-29 and 30-34 years old were 1.31 (1.28-1.35), 0.88 (0.86-0.90) and 0.89 (0.87-0.91) times of those aged ≥35 years old. The risks of low birth weight [OR (95%CI) value] of pregnancy BMI <18.5 and 18.5-23.9 kg/m(2) group were 1.98 (1.94-2.03) and 1.20 (1.18-1.23) times of those pregnancy BMI ≥24 kg/m(2). The risks of low birth weight [OR (95%CI) value] of pregnant women's height (cm)<145, 145-154, 155-159 and 160-164 cm were 4.67 (4.39-4.97), 2.36 (2.29-2.44), 1.58 (1.53-1.63) and 1.22 (1.18-1.26) times of those heights ≥165 cm group. The risks of low birth weight [OR (95%CI) value] of pregnant women's gestational age <28, 28-31 and 32-36 years old were 136.65 (124.33-150.20), 1 704.37 (1 509.02-1 925.02) and 33.45 (32.98-33.94) times of those gestational age ≥37 years old. Conclusion: The incidence of low birth weight of live births was higher in Guangxi from 2016 to 2018. There is a higher risk of low birth weight for younger, older, low height, low BMI and preterm women in Guangxi from 2016 to 2018.目的： 探讨广西活产儿、足月产儿出生体重的分布特征及相关因素。 方法： 依托"桂妇儿信息系统" ，全程记录2016—2018年广西1 712家助产机构住院分娩的孕产妇、活产儿住院分娩实时信息，共纳入活产儿2 394 240名，其中足月产儿2 243 129名。描述出生体重分布情况；采用多因素logistic回归模型分析低体重儿发生的相关因素。 结果： 活产儿出生体重为（3 123.49±461.08）g，近似服从正态分布（呈偏左尖峰分布）。低出生体重发生率为8.05%，巨大儿发生率为2.07%。产妇体重指数（BMI）<18.5 kg/m(2)者低出生体重发生率为10.92%，身高<145 cm者为16.82%，年龄<20岁者为8.92%，年龄≥35岁者为7.67%，<37孕周者为54.65%。2 243 129例足月产儿出生体重为（3 176.01±400.78）g，近似服从正态分布（呈偏右尖峰分布）。低体重儿发生率为2.97%，巨大儿发生率为2.19%。产妇BMI<18.5 kg/m(2)者低出生体重发生率为4.73%，身高<145 cm者为8.17%，年龄<20岁者为4.83%，年龄≥ 35岁者为3.05%。孕妇年龄<20、25~29、30~34岁组的低出生体重风险[OR（95%CI）值]分别是≥35岁组的1.31（1.28~1.35）、0.88（0.86~0.90）、0.89（0.87~0.91）倍；孕前BMI<18.5、18.5~23.9 kg/m(2)组分别是孕前BMI≥24 kg/m(2)孕妇的1.98（1.94~2.03）、1.20（1.18~1.23）倍；孕妇身高<145、145~154、155~159、160~164 cm组分别是身高≥165 cm组的4.67（4.39~4.97）、2.36（2.29~2.44）、1.58（1.53~1.63）、1.22（1.18~1.26）倍；孕周<28、28~31、32~36分别是孕周≥ 37的136.65（124.33~150.20）、1 704.37（1 509.02~1 925.02）、33.45（32.98~33.94）倍。 结论： 广西活产儿低出生体重发生率较高；小年龄及大年龄产妇、BMI偏低、身高偏低、早产产妇发生低出生体重风险较高。.