title: Correlates of physical activity at two time points during pregnancy.
abstract: BACKGROUND
  Correlates of prenatal physical activity can inform interventions, but are not well-understood.
  
  
  METHODS
  Participants in the Pregnancy, Infection, and Nutrition 3 Study were recruited before 20 weeks gestation. Women self-reported frequency, duration, and mode of moderate and vigorous physical activities. We used logistic regression to identify correlates of any physical activity (≥10 minutes/week of any mode), any recreational activity (≥10 minutes/week), and high volume recreational activity (either ≥150 minutes/week of moderate or ≥75 minutes/week of vigorous). Our analysis included 1752 women at 19-weeks gestation and 1722 at 29 weeks.
  
  
  RESULTS
  Higher education, white race, and enjoyment of physical activity were positively correlated with all 3 outcomes. Any recreational activity was negatively associated with parity, body mass index, and history of miscarriage. The associations of history of miscarriage and body mass index differed at 19 weeks compared with 29 weeks. Single marital status, health professional physical activity advice, and time for activity were associated with high volume recreational activity only.
  
  
  CONCLUSIONS
  Correlates of physical activity differed by mode and volume of activity and by gestational age. This suggests that researchers planning physical activity interventions should consider the mode and amount of activity and the gestational age of the participants.
authors.affiliation: Epidemiology Branch, National Institute of Environmental Health Sciences, Durham, NC, USA.
authors.forename: Marie Z
authors.initials: MZ
authors.lastname: Jukic A
authors.forename: Kelly R
authors.initials: KR
authors.lastname: Evenson
authors.forename: Amy H
authors.initials: AH
authors.lastname: Herring
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Wilcox
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Hartmann
authors.forename: Julie L
authors.initials: JL
authors.lastname: Daniels
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D016001:Confidence Intervals; D005260:Female; D005865:Gestational Age; D006801:Humans; D007899:Leisure Activities; D016015:Logistic Models; D008429:Maternal Welfare; D009043:Motor Activity / Q000502:physiology*; D016017:Odds Ratio; D011247:Pregnancy; D011295:Prenatal Care; D011594:Psychometrics; D011998:Recreation; D057566:Self Report; D011795:Surveys and Questionnaires; D013995:Time