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Five-millimeter and smaller embryos without embryonic cardiac activity: outcomes in women with vaginal bleeding
Seerat Aziz1, Richard C Cho, Diana B Baker
1Department of Radiology, University of California, San Francisco, California USA.
Objective:
The purpose of this study was to assess outcomes in embryos with a crown-rump length (CRL) of 5 mm or less without embryonic cardiac activity (ECA) among pregnant women with vaginal bleeding in the first trimester.
Methods:
A retrospective study of all first-trimester sonograms in women with vaginal bleeding from 1999 to 2002 was conducted.
Results:
Thirty-seven embryos without detectable ECA that had a CRL of 5 mm or less were identified. All resulted in pregnancy failure. The breakdown of these embryos by CRL was as follows: 13 were 5 mm; 10 ranged from 4 to 4.9 mm; 11 ranged from 3 to 3.9 mm; and 3 ranged from 2 to 2.9 mm.
Conclusions:
In pregnant women with vaginal bleeding, embryos of 5 mm and smaller without a heartbeat all resulted in pregnancy failure.
