A crown rump length (CRL) of ≥7 mm without a heartbeat on a endovaginal ultrasound confirms the diagnosis.
Additional clues are presence of abnormal hyperechoic material within the uterine cavity and an irregular gestational sac.
If there is an absence of the heartbeat in a fetus that is less than 7 mm, the diagnosis of miscarriage cannot be made with certainty. This scenario is termed "pregnancy of uncertain viability (PUV)", and follow up with ultrasound (generally in 7-10 days) and serial beta hCG levels recommended.
First trimester of pregnancy
- ultrasound findings in early pregnancy
- confirming intrauterine gestation
- pregnancy of unknown location (PUL)
first trimester vaginal bleeding
- ectopic pregnancy
failed early pregnancy
- pregnancy of uncertain viability (PUV)
- anembryonic pregnancy
- yolk sac abnormalities
- gestational trophoblastic disease
- subchorionic haemorrhage
- demise of a twin
- implantation bleeding
- aneuploidy testing
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