title: Early amniocentesis: outcome, risks, and technical problems at less than or equal to 12.8 weeks.
abstract: OBJECTIVE
  It is the purpose of this report to evaluate our experience with amniocentesis at less than or equal to 12 weeks' gestation.
  
  
  METHODS
  Medical records of 936 patients at less than or equal to 12.8 weeks' gestation undergoing genetic amniocentesis between Oct. 1, 1986, and June 30, 1990, were evaluated for gestational age, indication, frequency of needle insertion, amniocentesis complications, and pregnancy outcome.
  
  
  RESULTS
  There were seven miscarriages within 2 weeks of amniocentesis (0.7%), 21 miscarriages before 28 weeks (2.2%), and four stillbirths or neonatal deaths (0.4%), resulting in a total postprocedural loss rate of 3.4%. There were 26 chromosomally abnormal fetuses (2.8%). The spontaneous abortion rate in ultrasonographically normal pregnancies at less than 14 weeks, not undergoing amniocentesis, has been estimated at 2.1% to 3.2%.
  
  
  CONCLUSIONS
  Amniocentesis at 12 weeks is a viable option for patients desiring earlier prenatal genetic diagnostic information.
authors.affiliation: Department of Obstetrics and Gynecology, University of California, Davis.
authors.forename: F W
authors.initials: FW
authors.lastname: Hanson
authors.forename: F
authors.initials: F
authors.lastname: Tennant
authors.forename: S
authors.initials: S
authors.lastname: Hune
authors.forename: K
authors.initials: K
authors.lastname: Brookhyser
mesh_terms: D000649:Amniocentesis / Q000009:adverse effects; D005260:Female; D005313:Fetal Death / Q000209:etiology; D005865:Gestational Age; D006801:Humans; D016104:Oligohydramnios / Q000209:etiology; D011247:Pregnancy; D011256:Pregnancy Outcome; D012307:Risk Factors; D013997:Time Factors