HCG Levels and early Pregnancy

Q: At what hCG level should a pregnancy be seen?

A: The earliest sign of pregnancy, the gestational sac (GS), should be seen on transvaginal ultrasound by the time the hCG has reached 1500-2000 mIU/cc, though it's not unusual to see the GS even earlier. If the hCG is above 2000 mIU/cc and there is no GS seen on transvaginal ultrasound, then most doctors suspect an ectopic pregnancy.