This article does not cite any sources. (December 2009) (Learn how and when to remove this template message)
The fetal pole is a thickening on the margin of the yolk sac of a fetus during pregnancy. It is usually identified at 8 weeks with abdominal ultrasound imaging, and 6 weeks with vaginal ultrasound imaging. However it is quite normal for the fetal pole to not be visible until about 9 weeks. The fetal pole may be seen at 2–4 mm crown-rump length (CRL).
|This developmental biology article is a stub. You can help Wikipedia by expanding it.|