At what maternal serum beta-hCG level should a gestational sac normally be visible inside the uterus on TRANSVAGINAL ultrasound?

• A 500 to 1000 mIU/mL
• B 1500 to 2000 mIU/mL ✓
• C 3500 to 4000 mIU/mL
• D 6000 to 6500 mIU/mL

Explanation

The discriminatory zone for transvaginal sonography is approximately 1500 to 2000 mIU/mL (Third International Standard); above this level an intrauterine sac should be seen in a singleton pregnancy. Transabdominal scanning requires roughly double this level, about 6500 mIU/mL. An empty uterus with beta-hCG well above the discriminatory zone strongly suggests ectopic pregnancy or early failed pregnancy rather than a very early normal gestation.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.