Fetal heart beat
Citation, DOI and article data
Fetal heart beat can be detected as early as 34 days (just under 6 weeks) gestation on good quality, high frequency transvaginal ultrasound, as a crown rump length (CRL) of as little as 1-2 mm.
If a fetal heartbeat cannot be identified with a CRL ≥7 mm using transvaginal scanning, then embryonal demise can be diagnosed 3,4. Demise can be confirmed with repeated scanning and serial quantitative beta-HCG.
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