title: Vitamin C intake and the risk of preterm delivery.
abstract: OBJECTIVE
  Ascorbic acid deficiency may lead to premature rupture of the membranes.
  
  
  METHODS
  The study included a prospective cohort of pregnant women, aged >/=16 years, with singleton gestations who received care at one of four prenatal clinics in central North Carolina from 1995 through 1998. Vitamin C intake preconceptionally and during the second trimester was examined for its association with preterm delivery and subsets of preterm labor, premature rupture of the membranes, and medical induction in 2064 women.
  
  
  RESULTS
  Women who had total vitamin C intakes of <10th percentile preconceptionally had twice the risk of preterm delivery because of premature rupture of the membranes (relative risk, 2.2; 95% CI, 1.1, 4.5). This risk was attenuated slightly for second-trimester intake (relative risk, 1.7; 95% CI, 0.8, 3.5). The elevated risk of preterm premature rupture of the membranes was greatest for women with a low vitamin C intake during both time periods.
  
  
  CONCLUSIONS
  Because diet and supplement use are modifiable behaviors, corroboration of these findings would suggest a possible intervention strategy.
authors.affiliation: Department of Nutrition, School of Public Health, the Carolina Population Center, University of North Carolina, Chapel Hill, USA.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Siega-Riz
authors.forename: Joanne H E
authors.initials: JH
authors.lastname: Promislow
authors.forename: David A
authors.initials: DA
authors.lastname: Savitz
authors.forename: John M
authors.initials: JM
authors.lastname: Thorp
authors.forename: Thad
authors.initials: T
authors.lastname: McDonald
mesh_terms: D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage*; D015331:Cohort Studies; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007752:Obstetric Labor, Premature; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies; D012044:Regression Analysis; D012306:Risk
chemical_list: D000975:Antioxidants; D001205:Ascorbic Acid