title: Birth Defects Among Fetuses and Infants of US Women With Evidence of Possible Zika Virus Infection During Pregnancy.
abstract: Understanding the risk of birth defects associated with Zika virus infection during pregnancy may help guide communication, prevention, and planning efforts. In the absence of Zika virus, microcephaly occurs in approximately 7 per 10 000 live births.
  
  
  
  To estimate the preliminary proportion of fetuses or infants with birth defects after maternal Zika virus infection by trimester of infection and maternal symptoms.
  
  
  
  Completed pregnancies with maternal, fetal, or infant laboratory evidence of possible recent Zika virus infection and outcomes reported in the continental United States and Hawaii from January 15 to September 22, 2016, in the US Zika Pregnancy Registry, a collaboration between the CDC and state and local health departments.
  
  
  
  Laboratory evidence of possible recent Zika virus infection in a maternal, placental, fetal, or infant sample.
  
  
  
  Birth defects potentially Zika associated: brain abnormalities with or without microcephaly, neural tube defects and other early brain malformations, eye abnormalities, and other central nervous system consequences.
  
  
  
  Among 442 completed pregnancies in women (median age, 28 years; range, 15-50 years) with laboratory evidence of possible recent Zika virus infection, birth defects potentially related to Zika virus were identified in 26 (6%; 95% CI, 4%-8%) fetuses or infants. There were 21 infants with birth defects among 395 live births and 5 fetuses with birth defects among 47 pregnancy losses. Birth defects were reported for 16 of 271 (6%; 95% CI, 4%-9%) pregnant asymptomatic women and 10 of 167 (6%; 95% CI, 3%-11%) symptomatic pregnant women. Of the 26 affected fetuses or infants, 4 had microcephaly and no reported neuroimaging, 14 had microcephaly and brain abnormalities, and 4 had brain abnormalities without microcephaly; reported brain abnormalities included intracranial calcifications, corpus callosum abnormalities, abnormal cortical formation, cerebral atrophy, ventriculomegaly, hydrocephaly, and cerebellar abnormalities. Infants with microcephaly (18/442) represent 4% of completed pregnancies. Birth defects were reported in 9 of 85 (11%; 95% CI, 6%-19%) completed pregnancies with maternal symptoms or exposure exclusively in the first trimester (or first trimester and periconceptional period), with no reports of birth defects among fetuses or infants with prenatal exposure to Zika virus infection only in the second or third trimesters.
  
  
  
  Among pregnant women in the United States with completed pregnancies and laboratory evidence of possible recent Zika infection, 6% of fetuses or infants had evidence of Zika-associated birth defects, primarily brain abnormalities and microcephaly, whereas among women with first-trimester Zika infection, 11% of fetuses or infants had evidence of Zika-associated birth defects. These findings support the importance of screening pregnant women for Zika virus exposure.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Honein
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: April L
authors.initials: AL
authors.lastname: Dawson
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Emily E
authors.initials: EE
authors.lastname: Petersen
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Abbey M
authors.initials: AM
authors.lastname: Jones
authors.affiliation: New York City Department of Health and Mental Hygiene, Queens, New York.
authors.forename: Ellen H
authors.initials: EH
authors.lastname: Lee
authors.affiliation: Massachusetts Department of Public Health, Boston.
authors.forename: Mahsa M
authors.initials: MM
authors.lastname: Yazdy
authors.affiliation: New York State Department of Health, Albany.
authors.forename: Nina
authors.initials: N
authors.lastname: Ahmad
authors.affiliation: Virginia Department of Health, Richmond.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Macdonald
authors.affiliation: Texas Department of State Health Services, Austin.
authors.forename: Nicole
authors.initials: N
authors.lastname: Evert
authors.affiliation: Florida Department of Health, Tallahassee.
authors.forename: Andrea
authors.initials: A
authors.lastname: Bingham
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Sascha R
authors.initials: SR
authors.lastname: Ellington
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Carrie K
authors.initials: CK
authors.lastname: Shapiro-Mendoza
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Titilope
authors.initials: T
authors.lastname: Oduyebo
authors.affiliation: New York City Department of Health and Mental Hygiene, Queens, New York.
authors.forename: Anne D
authors.initials: AD
authors.lastname: Fine
authors.affiliation: Massachusetts Department of Public Health, Boston.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Brown
authors.affiliation: New York State Department of Health, Albany.
authors.forename: Jamie N
authors.initials: JN
authors.lastname: Sommer
authors.affiliation: Virginia Department of Health, Richmond.
authors.forename: Jyoti
authors.initials: J
authors.lastname: Gupta
authors.affiliation: Florida Department of Health, Tallahassee.
authors.forename: Philip
authors.initials: P
authors.lastname: Cavicchia
authors.affiliation: New York City Department of Health and Mental Hygiene, Queens, New York.
authors.forename: Sally
authors.initials: S
authors.lastname: Slavinski
authors.affiliation: New York State Department of Health, Albany.
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: White
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: S Michele
authors.initials: SM
authors.lastname: Owen
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Lyle R
authors.initials: LR
authors.lastname: Petersen
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Coleen
authors.initials: C
authors.lastname: Boyle
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Dana
authors.initials: D
authors.lastname: Meaney-Delman
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Denise J
authors.initials: DJ
authors.lastname: Jamieson
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000002:abnormalities* / Q000821:virology; D000013:Congenital Abnormalities / Q000453:epidemiology / Q000821:virology*; D005124:Eye Abnormalities / Q000821:virology*; D005260:Female; D005333:Fetus / Q000821:virology*; D006801:Humans; D007223:Infant; D008831:Microcephaly / Q000453:epidemiology / Q000821:virology; D008875:Middle Aged; D009436:Neural Tube Defects / Q000453:epidemiology / Q000821:virology*; D059906:Neuroimaging; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology; D014481:United States; D055815:Young Adult; D000071244:Zika Virus; D000071243:Zika Virus Infection / Q000453:epidemiology