title: Maternal weight and body composition in the first trimester of pregnancy.
abstract: OBJECTIVE
  Previous studies on weight gain in pregnancy suggested that maternal weight on average increased by 0.5-2.0 kg in the first trimester of pregnancy. This study examined whether mean maternal weight or body composition changes in the first trimester of pregnancy.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  We studied 1,000 Caucasian women booking for antenatal care in the first trimester of pregnancy.
  
  
  METHODS
  Large university teaching hospital.
  
  
  METHODS
  Maternal height and weight were measured digitally in a standardized way and Body Mass Index (BMI) was calculated. Maternal body composition was measured using segmental multifrequency Bioelectrical Impedance Analysis (BIA). Sonographic examination confirmed the gestational age and a normal ongoing singleton pregnancy in all subjects.
  
  
  METHODS
  Maternal weight, maternal body composition.
  
  
  RESULTS
  The mean BMI was 25.7 kg/m(2) and 19.0% of the women were in the obese category (> or =30.0 kg/m(2)). Cross-sectional analysis by gestational age showed that there was no change in mean maternal weight, BMI, total body water, fat mass, fat-free mass or bone mass before 14 weeks gestation.
  
  
  CONCLUSIONS
  Contrary to previous reports, mean maternal weight and mean body composition values remain unchanged in the first trimester of pregnancy. This has implications for guidelines on maternal weight gain during pregnancy. We also recommend that calculation of BMI in pregnancy and gestational weight gain should be based on accurate early pregnancy measurements, and not on self-reported or prepregnancy measurements.
authors.affiliation: UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Dublin, Ireland.
authors.forename: Chro
authors.initials: C
authors.lastname: Fattah
authors.forename: Nadine
authors.initials: N
authors.lastname: Farah
authors.forename: Sinead C
authors.initials: SC
authors.lastname: Barry
authors.forename: Norah
authors.initials: N
authors.lastname: O'Connor
authors.forename: Bernard
authors.initials: B
authors.lastname: Stuart
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Turner
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D047109:Fetal Development / Q000502:physiology; D006801:Humans; D008429:Maternal Welfare; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000502:physiology*; D011295:Prenatal Care / Q000379:methods; D011336:Probability; D011446:Prospective Studies; D012016:Reference Values; D013997:Time Factors; D016216:Ultrasonography, Prenatal; D015430:Weight Gain / Q000502:physiology