The Study Of Associations Of Gestational Weight Gain With Maternal And Child Health Outcomes And Methods Of Gestational Weight Management

Objective: Gestational weight gain is the most appropriate index of maternal nutrition and fetal intrauterine nutrition level during pregnancy,which is an important indicator for maternal and infant health status during pregnancy.Up to now,there is no suitable reference value for gestational weight gain or method of weight managementt in China.Therefore,the main purposes of this study are as follows: 1.To examine the association of prenatal body mass index(BMI),gestational weight gain(GWG)with adverse pregnancy outcomes such as macrosomia,low birth weight(LBW),larger than gestational age(LGA),smaller than gestational age(SGA),preterm birth(PTB),cesarean section,neonatal asphyxia,and pregnancy-specific diseases such as gestational diabetes mellitus and gestational hypertension.2.To examine the association of maternal BMI and GWG with infant overweight and obesity and infant development level.3.To explore the suitable range of gestational weight gain for pregnant women in China.4.To define the influencing factors of GWG and explore the methods of gestational weight management in Chinese population.Methods: In this prospective birth cohort study based on natural population,we investigated pregnant women and their infants in Shenyang.Based on the national three-level network of maternal and child health care.We used a stratified random sampling method to include the pregnant women in the second trimester(21-24 weeks of pregnancy)who met the inclusion criteria.We conducted follow up visits at third trimester of pregnancy(33-36 weeks of pregnancy),the time of delivery and the age of 1,3,6,8,12 month of infant.The survey methods of each period include: mid-pregnancy(questionnaire survey,physical examination,biological sample collection,clinical data collection);late pregnancy(questionnaire survey,physical examination,clinical data collection);infant stages(questionnaire survey,physical examination,child development diagnosis,clinical data collection).We used logistic regression,generalized linear regression and mixed effect model to examine the association of prenatal BMI status and GWG with adverse pregnancy outcomes,pregnancy-specific diseases,infant obesity and development level.The appropriate range of GWG was determined by prevalence method and quartile spacing method in healthy population,and compared with IOM 2009 guidelines in the United States.We determined the influencing factors of unsuitable GWG,and explored the appropriate reference values of relevant influencing factors,and further explored the methods of gestational weight management in Chinese pregnant women.Results: 1.Excessive GWG was a significant risk factor for macrosomia(OR = 2.86,95% CI: 1.78-2.16).The weight gain rate during pregnancy was significantly correlated with the risk of macrosomia(OR = 28.40,95% CI: 7.56-106.58).The weight gain rate in the first two trimester was significantly correlated with the risk of macrosomia(OR = 9.99,95% CI: 3.03-32.13).Insufficient GWG was a significant risk factor for LBW(OR = 4.93,95% CI: 1.65-14.66).Pre-pregnancy overweight was a significant risk factor for LGA(OR = 1.66,95% CI: 1.23-2.24).Excessive GWG was a significant risk factor for LGA(OR = 2.27,95% CI: 1.72-3.00).Pre-pregnancy obesity was a significant risk factor for PTB(OR = 3.55,95% CI: 1.73-7.30).Excessive GWG was a significant protective factor for PTB(OR = 0.52,95% CI: 0.28-0.99).Pre-pregnancy obesity was a significant risk factor for cesarean section(OR = 2.89,95% CI: 1.61-5.18).Pre-pregnancy overweight was a significant risk factor for GDM(OR = 1.92,95% CI: 1.35-2.74).Pre-pregnancy overweight and obesity were significant risk factors for pregnancy-induced hypertension(OR = 1.79,95% CI: 1.27-2.53),(OR = 3.89,95% CI: 2.43-6.22).2.The rates of overweight and obesity of infants aged 0,1,3,6,8 and 12 months were 10.77%,16.25%,25.61%,25.53%,24.57% and 30.95% respectively.Low-weight of pregnant women was associated with lower risk of overweight and obesity in the offspring of at 0,1,3 and 6 months of age(OR= 0.14,95% CI: 0.03-0.59),(OR= 0.51,95% CI: 0.26-0.98),(OR= 0.46,95% CI: 0.26-0.81),(OR= 0.54,95% CI: 0.31-0.95);pre-pregnancy obesity was associated with higher risk of infat aged 6,8 and 12 months(OR = 2.30,95% CI: 1.33-3.98),(OR = 2.02,95% CI: 1.18-3.46),(OR = 1.96,95% CI: 1.16-3.30).The offspring of pregnant women with excessive GWG had a higher risk of overweight and obesity at the age of 0 and 1 month(OR = 2.72,95% CI: 1.52-4.88),(OR = 1.55,95% CI: 1.01-2.38),and had a higher risk of obesity at the age of 12 months(OR = 2.84,95% CI: 1.38-5.86).The effect of GWG on children's weight was significant in early and mid-pregnancy(?=0.64,0.39-1.34),but not in late pregnancy.Pre-pregnancy low weight was a protective factor for slow development of large and fine motor in 7-month-old infants(OR = 0.37,95% CI: 0.15-0.87),(OR = 0.43,95% CI: 0.19-0.98).Excessive GWG in pregnant women was a risk factor for slow social development of infants at 7 months of age(OR = 2.45,95% CI: 1.12-5.37).3.According to the prevalence method,the suitable GWG of low-weight pre-pregnant women is 14.0-18.0 kg,that of normal-weight pre-pregnant women is 10.0-16.0 kg,and that of overweight and obese pre-pregnant women is 10.0-14.0 kg.According to the quartile method,the suitable GWG of low-weight pre-pregnant women is 14.5-19.0 kg,that of normal-weight pre-pregnant women is 13.0-19.0 kg,and that of overweight and obese pre-pregnant women is 11.0-17.0 kg.The incidence of overweight and obesity in 6-month-old infants delivered by pregnant women who met the GWG reference values recommended by this study(prevalence method,healthy population quartile method)was lower than that of pregnant women who met the IOM2009 standard.4.Based on the GWG reference value determined by the prevalence rate method,in order to reach the appropriate GWG level,the BMI before pregnancy should be controlled in the range of 19-22 kg/m2;the average daily energy intake in the second trimester of pregnancy of low-weight pre-pregnant women should be 1740-1905 Kcal;the average daily energy intake in the second trimester of pregnancy of normal-weight pre-pregnant women should be 2062-2489 Kcal;and the average daily energy intake in the second trimester of overweight and obese pre-pregnant women of pregnancy should be 1095 Kcal.-2062 Kcal;Weekly physical activity level of low-weight pre-pregnant women should be controlled at 14.9-24.6 MET;Weekly physical activity level of normal-weight pre-pregnant women should be controlled at 31.2-42.6 MET;Weekly physical activity level of overweight and obese pre-pregnant women should be controlled at 24.6-31.2 MET;Sleep quality score of pregnant women should be controlled below 7 points during the second trimester of pregnancy(measured by Pittsburgh sleep index scale).The pregnancy stress score of pregnant women in the second trimester should be controlled below 39 points(measured by pregnancy stress scale);the depression score of pregnant women in the second trimester should be controlled below 4 points(measured by Edinburgh depression index).According to this management method,the risk of unsuitable GWG in pregnant women can be reduced by 63%.Conclusions: Pre-pregnancy weight status and gestational weight gain are associated with health outcomes mothers and infants.The gestational weight gain standard for Chinese population is significantly different from that of IOM2009 in the United States.Diet and physical activity during pregnancy are key factors in managing gestational weight.The recommended method of gestational weight management in this study is practical and effective.It is suggested that on this basis,the guidelines for gestational weight management in Chinese population should be further developed.