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
Hormone balance is essential for maintaining a normal pregnancy. Early on, elevated progesterone levels are needed to maintain pregnancy and progesterone is produced in excess by the corpus luteum. In the normal menstrual cycle the corpus luteum involutes, but this process is impeded during pregnancy because of the presence of which hormone?
assistant
Human chorionic gonadotropin