title: Pregnancy outcome after exposure to ranitidine and other H2-blockers. A collaborative study of the European Network of Teratology Information Services.
abstract: BACKGROUND
  Published data on pregnancy outcome after exposure to H2-blockers is scarce. The aim of the present study was to evaluate the data collected by the memberships of the European Network of Teratology Information Services (ENTIS).
  
  
  METHODS
  The patients were pregnant women who or whose doctor or midwife did contact a Teratology Information Service for risk assessment after the use of a H2-blocker in pregnancy. The data were prospectively collected, i.e. before the outcome of pregnancy was known. Standardized procedures for data collection were used by each centre. The data of the exposed women were compared to those of a control group exposed to non-teratogenic substances.
  
  
  RESULTS
  Data on the outcome of 553 pregnancies with exposure to an H2-blocker were evaluated (ranitidine n=335; cimetidine n=113, famotidine n=75; nizatidine n=15, roxatidine n=15). Most of them had been exposed at least in the first trimester. The incidence of premature deliveries was higher in the exposed group compared to the control group. There was no increase in the incidence of major malformations. Two pregnancies with maternal use of famotidine in early pregnancy were terminated after the prenatal diagnosis of a neural tube defect.
  
  
  CONCLUSIONS
  There is no indication for an increased risk of major malformations after the use of H2-blockers during pregnancy.
authors.affiliation: Teratology Information Service, National Institute of Public Health and Environment, P.O. Box 1, 3720 BA Bilthoven, The Netherlands. hanneke.garbis@rivm.nl
authors.forename: Hanneke
authors.initials: H
authors.lastname: Garbis
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Elefant
authors.forename: Orna
authors.initials: O
authors.lastname: Diav-Citrin
authors.forename: Pierpaolo
authors.initials: P
authors.lastname: Mastroiacovo
authors.forename: Christof
authors.initials: C
authors.lastname: Schaefer
authors.forename: Thierry
authors.initials: T
authors.lastname: Vial
authors.forename: Maurizio
authors.initials: M
authors.lastname: Clementi
authors.forename: Electra
authors.initials: E
authors.lastname: Valti
authors.forename: Patricia
authors.initials: P
authors.lastname: McElhatton
authors.forename: Carlo
authors.initials: C
authors.lastname: Smorlesi
authors.forename: Elvira Pinilla
authors.initials: EP
authors.lastname: Rodriguez
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Robert-Gnansia
authors.forename: Paul
authors.initials: P
authors.lastname: Merlob
authors.forename: Gertrud
authors.initials: G
authors.lastname: Peiker
authors.forename: Tomas
authors.initials: T
authors.lastname: Pexieder
authors.forename: Lavinia
authors.initials: L
authors.lastname: Schueler
authors.forename: Annukka
authors.initials: A
authors.lastname: Ritvanen
authors.forename: Monique
authors.initials: M
authors.lastname: Mathieu-Nolf
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000453:epidemiology / Q000209:etiology*; D000328:Adult; D016022:Case-Control Studies; D005060:Europe / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005865:Gestational Age; D006635:Histamine H2 Antagonists / Q000009:adverse effects*; D006801:Humans; D007231:Infant, Newborn; D007391:International Cooperation; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D011899:Ranitidine / Q000009:adverse effects*; D018570:Risk Assessment
chemical_list: D006635:Histamine H2 Antagonists; D011899:Ranitidine