In OBGYN, the gestational sac is the first sonographic sign of an intrauterine pregnancy, appearing as a small, fluid-filled structure within the uterus. It typically becomes visible via transvaginal ultrasound around 4.5 to 5 weeks of gestation. This sac encloses the developing embryo and yolk sac, providing essential early nourishment and protection. Identifying the gestational sac is crucial for confirming pregnancy, assessing its location, and estimating gestational age.
Its presence on ultrasound confirms an early viable pregnancy within the uterine cavity, helping clinicians differentiate it from ectopic pregnancies. Monitoring the gestational sac’s size and growth is vital for early pregnancy assessment, aiding in the diagnosis of potential complications. This makes the gestational sac a cornerstone for early medical and ultrasound evaluations in obstetrics and gynecology.
