title: The impact of change in pregnancy body mass index on macrosomia.
abstract: OBJECTIVE
  To examine the impact of change in body mass index (BMI) during pregnancy on the incidence of macrosomia.
  
  
  METHODS
  This is a retrospective cohort study using 2007 linked birth certificate and discharge diagnosis data from the state of California. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) were calculated for the outcome of macrosomia, as a function of a categorical change in pregnancy BMI: BMI loss (<-0.5), no change (-0.5 to 0.5), minimal (0.6 to 5), moderate (5.1 to 10), and excessive (>10). The impact of pregnancy change in BMI was determined for the entire cohort and then stratified by prepregnancy BMI category. Minimal BMI change served as the reference group.
  
  
  RESULTS
  The study population consisted of 436,414 women. Overall, women with moderate and excessive BMI changes had aORs of 1.66 and 3.21, respectively, for macrosomia, when compared with women with minimal BMI change. When stratified by prepregnancy BMI, normal (aOR 3.85) and overweight women (aOR 2.96) with antenatal BMI change greater than 10 had the highest odds of macrosomia.
  
  
  CONCLUSIONS
  Excessive change in pregnancy BMI results in an increased odds of macrosomia. This finding was most pronounced in the normal and overweight women.
authors.affiliation: University of California, Irvine Medical Center, Orange, California, USA.
authors.forename: Morgan L
authors.initials: ML
authors.lastname: Swank
authors.forename: Aaron B
authors.initials: AB
authors.lastname: Caughey
authors.forename: Christine K
authors.initials: CK
authors.lastname: Farinelli
authors.forename: Elliott K
authors.initials: EK
authors.lastname: Main
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Melsop
authors.forename: William M
authors.initials: WM
authors.lastname: Gilbert
authors.forename: Judith H
authors.initials: JH
authors.lastname: Chung
mesh_terms: D000328:Adult; D001724:Birth Weight; D015992:Body Mass Index; D002140:California / Q000453:epidemiology; D005260:Female; D005320:Fetal Macrosomia / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D050177:Overweight / Q000150:complications / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D015430:Weight Gain / Q000502:physiology*; D055815:Young Adult