[Relationship between the pre-pregnancy BMI, gestational weight gain, and risk of preeclampsia and its subtypes].

Objective: To explore the effects of maternal pre-pregnancy body mass index (BMI) and gestational weight gain and its subtypes on the risk of preeclampsia. Methods: Pregnant women delivered in the Department of Obstetrics and Gynecology of the First Affiliated Hospital of Shanxi Medical University from March 2012 to September 2016 were selected as the research subjects. According to the inclusion and exclusion criteria, 9 274 pregnant women were included. 901 preeclampsia pregnant women were selected as the case group, and 8 373 non-preeclampsia pregnant women were selected as the control group. General demographic characteristics, pre-pregnancy weight, height, lifestyle during pregnancy, reproductive history, and disease history of pregnant women were collected, and pre-pregnancy BMI and gestational weight gain were calculated. Unconditional logistic regression was used to analyze the relationship between pre-pregnancy BMI and weight gain during pregnancy and PE and its clinical subtypes. Results: Among the 901 preeclampsia after inclusion and exclusion, 401 cases were diagnosed as early-onset PE (EOPE), 500 cases were late-onset PE (LOPE), 178 cases were Mild PE (MPE), and 723 cases were severe PE (SPE). There were statistically significant differences between PE and non-PE pregnant women in terms of maternal age, residence, parity, family history of gestational diabetes and hypertension (P<0.05). After adjusting for the above factors, the logistic regression analysis results showed that pre-pregnancy BMI<18.5 kg/m2 and inadequate gestational weight gain were protective factors for PE (OR=0.74, 95%CI: 0.56-0.98; OR=0.78, 95%CI: 0.62-0.99), while pre-pregnancy BMI≥24.0 kg/m2 and excessive gestational weight gain were risk factors for PE (OR=1.82, 95%CI: 1.54-2.14; OR=1.82, 95%CI: 1.54-2.15). After subtype analysis on PE, the results showed that pre-pregnancy BMI<18.5 kg/m2 was a protective factor for EOPE and MPE (OR=0.52, 95%CI: 0.32-0.83; OR=0.47, 95%CI: 0.23-0.97), while pre-pregnancy BMI≥24.0 kg/m2 and excessive gestational weight gain were risk factors for clinical subtypes of PE. After stratification according to pre-pregnancy BMI, excessive gestational weight gain was the risk factor for PE (OR=1.86, 95%CI: 1.51-2.30; OR=1.90, 95%CI: 1.39-2.60) in pregnant women 18.5 kg/m2≤BMI<24.0 kg/m2 and ≥24.0 kg/m2. Inadequate gestational weight gain (OR=0.55, 95%CI: 0.34-0.89) was a protective factor for PE in pregnant women with pre-pregnancy BMI≥24.0 kg/m2. Excessive gestational weight gain (OR=4.05, 95%CI: 1.20-13.69) was a risk factor for EOPE in pregnant women with pre-pregnancy BMI<18.5 kg/m2. Excessive gestational weight gain was a risk factor for the clinical subtype of PE in pregnant women 18.5 kg/m2≤BMI<24.0 kg/m2 before pregnancy. Inadequate gestational weight gain was a protective factor for EOPE and MPE (OR=0.39, 95%CI: 0.19-0.80; OR=0.29, 95%CI: 0.11-0.77) in pregnant women with pre-pregnancy BMI≥24.0 kg/m2. Excessive weight gain was a risk factor for EOPE, LOPE and SPE (OR=1.60, 95%CI: 1.06-2.42;OR=2.20, 95%CI: 1.44-3.37;OR=2.28, 95%CI: 1.58-3.29). Conclusions: Pre-pregnancy BMI and gestational weight gain affect the risk of preeclampsia and its clinical subtypes. In contrast, the influence of gestational weight gain on preeclampsia varies among different pre-pregnancy BMI groups. Therefore, it is recommended to pay attention to the changes in pre-pregnancy BMI and gestational weight gain simultaneously to reduce preeclampsia.目的： 探讨孕前BMI和孕期增重与子痫前期（PE）及其临床亚型的发生风险的关系。 方法： 选取2012年3月至2016年9月在山西医科大学第一医院妇产科分娩的孕妇，根据纳入排除标准，共纳入9 274例孕妇，901例PE孕妇作为病例组，8 373例非PE孕妇作为对照组。收集一般人口学特征、孕前身高和体重、孕期生活方式、生育史和疾病史等资料，计算孕前BMI及孕期增重。采用非条件logistic回归分析孕前BMI和孕期增重与PE及其临床亚型的关系。 结果： PE中早发型PE（EOPE）401例、晚发型PE（LOPE）500例，轻度PE（MPE）178例、重度PE（SPE）723例。PE孕妇和非PE孕妇在年龄、居住地、产次、妊娠期糖尿病及高血压家族史等方面差异有统计学意义（P<0.05）。调整以上因素后，logistic回归分析结果显示，孕前BMI<18.5 kg/m2和孕期增重不足是PE的保护因素（OR=0.74，95%CI：0.56~0.98；OR=0.78，95%CI：0.62~0.99），孕前BMI≥24.0 kg/m2和孕期增重过多是PE的危险因素（OR=1.82，95%CI：1.54~2.14；OR=1.82，95%CI：1.54~2.15）。对PE临床亚型分析后结果显示，孕前BMI<18.5 kg/m2是EOPE和MPE的保护因素（OR=0.52，95%CI：0.32~0.83；OR=0.47，95%CI：0.23~0.97），孕前BMI≥24.0 kg/m2和孕期增重过多是PE临床亚型的危险因素。按孕前BMI分层后，孕前18.5 kg/m2≤BMI<24.0 kg/m2和孕前BMI≥24.0 kg/m2的孕妇中孕期增重过多（OR=1.86，95%CI：1.51~2.30；OR=1.90，95%CI：1.39~2.60）均是PE的危险因素；孕前BMI≥24.0 kg/m2的孕妇中孕期增重不足（OR=0.55，95%CI：0.34~0.89）是PE的保护因素。孕前BMI<18.5 kg/m2的孕妇中孕期增重过多（OR=4.05，95%CI：1.20~13.69）是EOPE的危险因素；孕前18.5 kg/m2≤BMI<24.0 kg/m2的孕妇中孕期增重过多是PE各临床亚型的危险因素；孕前BMI≥24.0 kg/m2的孕妇中孕期增重不足是EOPE和MPE的保护因素（OR=0.39，95%CI：0.19~0.80；OR=0.29，95%CI：0.11~0.77），孕期增重过多是EOPE、LOPE和SPE的危险因素（OR=1.60，95%CI：1.06~2.42；OR=2.20，95%CI：1.44~3.37；OR=2.28，95%CI：1.58~3.29）。 结论： 孕前BMI和孕期增重影响PE及其临床亚型的发生风险，且不同孕前BMI人群孕期增重对PE的影响有差异，提倡同时关注孕前BMI和孕期体重变化，从而减少PE发生。.