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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 pearl index indicates teh number of accidental pregnancies per -
assistant
The correct answer is  park's textbook of preventive and social medicine 23rd edition. *pearl index is defined as the no of failure per 100 women year of exposure.