system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
At what level of b-hCG is it that normal pregnancy can be earliest detected by TVS (transvaginal USG)?
assistant
The correct answer is  Ans. is b, i.e. 1000IU/MLRef Dutta Obs. 7/e, p 642Critical titre of hCG:b-hCG level (mIU/ml)Structure visibleTVS/TAS* 1000-1200Gestational sacTVS* 6000Gestational SacTAS