Pregnancy
A gestational sac can usually be seen from about five weeks on a transvaginal scan, before the embryo itself. Its presence in the uterus is reassuring against an ectopic pregnancy but does not yet confirm a viable pregnancy, which is why a follow-up scan is arranged.
Also known as: pregnancy sac
Related Australia guides
Sources
- Royal Australian and New Zealand College of Obstetricians and Gynaecologists (ranzcog.edu.au)
- Healthdirect Australia (healthdirect.gov.au)
Last reviewed: 10 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.