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Published on: October 25, 2015
Early amniocentesis: outcome, risks, and technical problems at less than or equal to 12.8 weeks
F W Hanson1, F Tennant, S Hune
1Department of Obstetrics and Gynecology, University of California, Davis.
Objective:
It is the purpose of this report to evaluate our experience with amniocentesis at less than or equal to 12 weeks' gestation.
Study Design:
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%.
Conclusion:
Amniocentesis at 12 weeks is a viable option for patients desiring earlier prenatal genetic diagnostic information.
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