title: Fetal risk associated with rubella vaccination during pregnancy.
abstract: BACKGROUND
  Costa Rica implemented a nationwide measles-rubella vaccination campaign among men and women (15-39 years old) in May 2001. A protocol was developed to follow-up the vaccinated women who were unknowingly pregnant, to determine the risk of congenital rubella syndrome (CRS) or congenital rubella infection only associated with the administration of the rubella vaccine RA27/3 during pregnancy.
  
  
  METHODS
  To classify the prevaccination maternal immune status, a serum sample was taken at the initial evaluation to detect IgM and IgG rubella antibodies (enzyme-linked immunosorbent assay). All pregnancies were followed up and all newborns were evaluated. A cord serum sample of their children was taken at birth. We calculated odds ratio, OR (95% confidence interval, 95% CI) associated with miscarriage, stillbirth, prematurity, low birth weight, and the presence of defects compatible with CRS.
  
  
  RESULTS
  The prevaccination immune status was established in 797 women and 1191 mother and child pairs were analyzed. Adjusted OR for miscarriage (OR = 0.60, 95% CI = 0.26-1.39), stillbirth (OR = 1.32, 95% CI = 0.10-16.81), prematurity (OR = 0.25, 95% CI = 0.03-2.39), low birth weight (OR = 0.25, 95% CI = 0.03-2.23) and defects compatible with CRS (OR = 1.09, 95% CI = 0.34-3.54) showed no association between immune and susceptible maternal status. There were no cases of CRS and no children were IgM positive.
  
  
  CONCLUSIONS
  No adverse pregnancy outcome such as miscarriages or CRS was documented in women who were vaccinated and unknowingly pregnant. These results support RA27/3 rubella vaccine safety.
authors.affiliation: Social Security System of Costa Rica, San José, Costa Rica.
authors.forename: Xiomara
authors.initials: X
authors.lastname: Badilla
authors.forename: Ana
authors.initials: A
authors.lastname: Morice
authors.forename: Maria L
authors.initials: ML
authors.lastname: Avila-Aguero
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Saenz
authors.forename: Ilse
authors.initials: I
authors.lastname: Cerda
authors.forename: Susan
authors.initials: S
authors.lastname: Reef
authors.forename: Carlos
authors.initials: C
authors.lastname: Castillo-Solórzano
mesh_terms: D000293:Adolescent; D000328:Adult; D003364:Costa Rica / Q000453:epidemiology; D016208:Databases, Factual; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005333:Fetus / Q000187:drug effects* / Q000821:virology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007231:Infant, Newborn; D008297:Male; D032541:Mass Vaccination; D011247:Pregnancy / Q000276:immunology; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology / Q000276:immunology; D011256:Pregnancy Outcome / Q000453:epidemiology*; D012409:Rubella / Q000151:congenital* / Q000276:immunology* / Q000517:prevention & control; D012411:Rubella Vaccine / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M; D012411:Rubella Vaccine