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Fertility Glossary

Gestational Sac

The first ultrasound-visible sign of pregnancy in the uterus.

Pregnancy after fertility treatment

The gestational sac is usually visible from about 5 weeks of pregnancy.

Also known as: pregnancy sac, sac

Related United Kingdom guides

Last reviewed: 23 September 2026. Written by the Antega Editorial Team. General information only — always follow the advice of your own clinic, doctor or pharmacist.

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