title: Pre-Pregnancy Body Mass Index, Gestational Weight Gain, and Birth Weight: A Cohort Study in China.
abstract: OBJECTIVE
  To assess whether pre-pregnancy body mass index (BMI) modify the relationship between gestational weight gain (GWG) and child birth weight (specifically, presence or absence of low birth weight (LBW) or presence of absence of macrosomia), and estimates of the relative risk of macrosomia and LBW based on pre-pregnancy BMI were controlled in Wuhan, China.
  
  
  METHODS
  From June 30, 2011 to June 30, 2013. All data was collected and available from the perinatal health care system. Logistic regression models were used to estimate the independent association among pregnancy weight gain, LBW, normal birth weight, and macrosomia within different pre-pregnancy BMI groups. We built different logistic models for the 2009 Institute of Medicine (IOM) Guidelines and Chinese-recommended GWG which was made from this sample. The Chinese-recommended GWG was derived from the quartile values (25th-75th percentiles) of weight gain at the time of delivery in the subjects which comprised our sample.
  
  
  RESULTS
  For LBW children, using the recommended weight gain of the IOM and Chinese women as a reference, the OR for a pregnancy weight gain below recommendations resulted in a positive relationship for lean and normal weight women, but not for overweight and obese women. For macrosomia, considering the IOM's recommended weight gain as a reference, the OR magnitude for pregnancy weight gain above recommendations resulted in a positive correlation for all women. The OR for a pregnancy weight gain below recommendations resulted in a negative relationship for normal BMI and lean women, but not for overweight and obese women based on the IOM recommendations, significant based on the recommended pregnancy weight gain for Chinese women. Of normal weight children, 56.6% were above the GWG based on IOM recommendations, but 26.97% of normal weight children were above the GWG based on Chinese recommendations.
  
  
  CONCLUSIONS
  A GWG above IOM recommendations might not be helpful for Chinese women. We need unified criteria to classify adult BMI and to expand the sample size to improve representation and to elucidate the relationship between GWG and related outcomes for developing a Chinese GWG recommendation.
authors.affiliation: Department of Primary Guidance, Wuhan Women and Children Health Care Center, Wuhan, Hubei Province, 430015, China.
authors.forename: Shaoping
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Primary Guidance, Wuhan Women and Children Health Care Center, Wuhan, Hubei Province, 430015, China.
authors.forename: Anna
authors.initials: A
authors.lastname: Peng
authors.affiliation: Key Laboratory of Environment and Health, Ministry of Education & Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wei
authors.affiliation: Key Laboratory of Environment and Health, Ministry of Education & Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Primary Guidance, Wuhan Women and Children Health Care Center, Wuhan, Hubei Province, 430015, China.
authors.forename: Jinzhu
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Primary Guidance, Wuhan Women and Children Health Care Center, Wuhan, Hubei Province, 430015, China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Maternal and Children Health Care Department of Districts of Wuhan, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Maternal and Children Health Care Department of Districts of Wuhan, Wuhan, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Maternal and Children Health Care Department of Districts of Wuhan, Wuhan, China.
authors.forename: Yuzhen
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Department of Primary Guidance, Wuhan Women and Children Health Care Center, Wuhan, Hubei Province, 430015, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
mesh_terms: D000328:Adult; D001724:Birth Weight; D015992:Body Mass Index; D002681:China; D015331:Cohort Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D016017:Odds Ratio; D011247:Pregnancy; D062486:Public Health Surveillance; D015430:Weight Gain