fetal pole

The fetal pole is the first direct imaging manifestation of the fetus and is seen as a thickening on the margin of the yolk sac during early pregnancy. It is often used synonymously with the term "embryo".

The fetal pole is usually identified at ~6.5 weeks with transabdominal ultrasound imaging and at ~6 weeks  with transvaginal ultrasound imaging, although it may not be seen until ~9 weeks in some cases.

• a fetal pole should be seen when MSD ≥16 mm on TVS (by RCOG criteria), or MSD ≥25 mm on TAS
• pregnancy failure is not diagnosed until a fetal pole is not seen when MSD ≥25 mm on TVS

When the fetal pole measures ≥7 mm, a fetal heartbeat should be detected.

Siehe auch:

• Dottersack
• early pregnancy

und weiter:

• sonographic values in obstetrics and gynaecology
• mean sac diameter
• embryonal demise
• pregnancy of uncertain viability