title: Social inequality in pre-pregnancy BMI and gestational weight gain in the first and second pregnancy among women in Sweden.
abstract: BACKGROUND
  High pre-pregnancy body mass index (BMI) and inappropriate gestational weight gain (GWG) are associated with adverse short and long-term maternal and neonatal outcomes and may act as modifiable risk factors on the path to overweight/obesity, but their social patterning is not well established. This study investigates the association of education with BMI and GWG across two consecutive pregnancies.
  
  
  METHODS
  The study includes 163,352 Swedish women, having their first and second singleton birth in 1982-2010. In both pregnancies, we investigated the association of women's education with (1) pre-pregnancy weight status and (2) adequacy of GWG. We used multinomial logistic regression, adjusting for child's birth year, mother's age and smoking status.
  
  
  RESULTS
  Overall, the odds of starting either pregnancy at an unhealthy BMI were higher among women with a low education compared to more highly-educated women. Lower education also predicted a greater increase in BMI between pregnancies, with this effect greatest among women with excessive GWG in the first pregnancy (p<0.0001 for interaction). Education was also inversely associated with odds of excessive GWG in both pregnancies among healthy weight status women, but this association was absent or even weakly reversed among overweight and obese women.
  
  
  CONCLUSIONS
  Lower educated women had the largest BMI increase between pregnancies, and these inequalities were greatest among women with excessive GWG in the first pregnancy. The importance of a healthy pre-pregnancy BMI, appropriate GWG and a healthy postpartum weight should be communicated to all women, which may assist in reducing existing social inequalities in body weight.
authors.affiliation: Centre for Longitudinal and Life Course Research, School of Public Health, University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Natalie
authors.initials: N
authors.lastname: Holowko
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska Institutet, Stockholm, Sweden.
authors.forename: M Pia
authors.initials: MP
authors.lastname: Chaparro
authors.affiliation: Department of Sociology, Umeå University, Umeå, Sweden.
authors.forename: Karina
authors.initials: K
authors.lastname: Nilsson
authors.affiliation: Department of Public Health and Clinical Medicine, Epidemiology and Global Health, Umeå University, Umeå, Sweden.
authors.forename: Anneli
authors.initials: A
authors.lastname: Ivarsson
authors.affiliation: Centre for Longitudinal and Life Course Research, School of Public Health, University of Queensland, Brisbane, Queensland, Australia.
authors.forename: Gita
authors.initials: G
authors.lastname: Mishra
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska Institutet, Stockholm, Sweden Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Ilona
authors.initials: I
authors.lastname: Koupil
authors.affiliation: Centre for Health Equity Studies (CHESS), Stockholm University/Karolinska Institutet, Stockholm, Sweden Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Anna
authors.identifier: http://orcid.org/0000-0001-9995-6659
authors.initials: A
authors.lastname: Goodman
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015897:Comorbidity; D004522:Educational Status; D005260:Female; D006801:Humans; D016015:Logistic Models; D009765:Obesity / Q000191:economics* / Q000453:epidemiology; D016017:Odds Ratio; D050177:Overweight / Q000191:economics / Q000453:epidemiology; D011247:Pregnancy; D012042:Registries; D012907:Smoking / Q000453:epidemiology*; D012959:Socioeconomic Factors; D013548:Sweden / Q000453:epidemiology; D013851:Thinness / Q000191:economics* / Q000453:epidemiology; D015430:Weight Gain
keywords: OBESITY; PREGNANCY; REPRODUCTIVE HEALTH; SOCIAL INEQUALITIES