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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
The foetal pole with cardiac activity is detected with Transvaginal USG by what stage of gestation?
assistant
The correct answer is  Using transvaginal USG, the gestational sac can usually be seen at 4 weeks, the yolk sac at 5 weeks, and the fetal pole with cardiac activity by 6 weeks. Cardiac activity can be seen simultaneously with the appearance of a fetal pole as a pulsation at the lateral aspect of the yolk sac. Normal embryonic hea rate may be as low as 70-100 beats per minute range during early gestation, but soon rises to the fetal normal range of 120-160 beats/min by 9-10 weeks gestational age.