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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.
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Define perinatal period?
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The correct answer is  Perinatal period: The interval between the bih of an infant born after 20 weeks' gestation and the 28 completed days after that bih. When perinatal rates are based on bihweight, rather than gestational age, it is recommended that the perinatal period is defined as commencing at 500 g.Ref: William&;s Obstetrics; 24th edition; Chapter 1; Overview of Obstetrics