title: Association between gestational night blindness and serum retinol in mother/newborn pairs in the city of Rio de Janeiro, Brazil.
abstract: OBJECTIVE
  Gestational night blindness (XN) is associated with increased risk of reproductive morbidity and mortality. This study investigated the prevalence of gestational XN among postpartum women treated in a public maternity hospital in the city of Rio de Janeiro, Brazil and evaluated its association with maternal and neonatal (cord blood) serum retinol concentrations.
  
  
  METHODS
  XN was evaluated retrospectively, using an interview according to guidelines of the World Health Organization, in 222 postpartum women (< or = 6 h after delivery) after singleton births who had low obstetric risk. Serum retinol concentrations were measured according to the modified Bessey method, with a cutoff point lower than 1.05 micromol/L for inadequate serum retinol concentration.
  
  
  RESULTS
  Prevalence of gestational XN was 18%, and inadequate maternal and cord blood serum retinol concentrations were found in 24.4% and 45.5% of samples, respectively. The results associated gestational XN with inadequate maternal serum retinol concentration (P = 0.000), and an association was observed between maternal and neonatal serum retinol concentrations (P = 0.000). A poor association was observed between maternal XN and serum levels of retinol in newborn children (P = 0.06).
  
  
  CONCLUSIONS
  The results suggest that prevalence of gestational XN and inadequate serum retinol concentration among postpartum women and newborns is a concern, calling attention to the need for studies in other parts of Brazil. In addition, the risk of inadequate serum retinol in newborns was significantly higher among infants of postpartum women with serum retinol levels below 1.05 micromol/L. Gestational XN was associated with inadequate levels of maternal serum retinol, and the results suggest a poor relation between maternal XN and vitamin A nutritional status of newborns.
authors.affiliation: National School of Public Health, Oswaldo Cruz Foundation, Rio de Janeiro, Rio de Janeiro, Brazil. cfcoelho@osite.com.br
authors.forename: Cláudia
authors.initials: C
authors.lastname: Saunders
authors.forename: Rejane Andréa
authors.initials: RA
authors.lastname: Ramalho
authors.forename: Ana Paula Pereira Thiapó
authors.initials: AP
authors.lastname: de Lima
authors.forename: Mirian Martins
authors.initials: MM
authors.lastname: Gomes
authors.forename: Luciana Ferreira
authors.initials: LF
authors.lastname: Campos
authors.forename: Bianca Amaral
authors.initials: BA
authors.lastname: dos Santos Silva
authors.forename: Alexandre
authors.initials: A
authors.lastname: Gonçalves Soares
authors.forename: Maria
authors.initials: M
authors.lastname: do Carmo Leal
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D016009:Chi-Square Distribution; D015897:Comorbidity; D005260:Female; D005312:Fetal Blood; D006801:Humans; D007231:Infant, Newborn; D007407:Interviews as Topic; D009755:Night Blindness / Q000097:blood / Q000453:epidemiology*; D009752:Nutritional Status / Q000502:physiology; D049590:Postpartum Period / Q000097:blood; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000453:epidemiology; D012189:Retrospective Studies; D014801:Vitamin A / Q000097:blood*; D014802:Vitamin A Deficiency / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D014801:Vitamin A