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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
In what period, following delivery, does the cardiac output return to the pre-pregnancy state?
assistant
The correct answer is  Cardiac output returns to pre labour values by one hour following delivery and pre pregnancy level by 4 weeks. Cardiac output: It stas to increase from 5th week of pregnancy reaches a peak 40-50% at about 30-34 weeks. It increases fuher during labour (50%) and immediately following delivery (70%) over pre labour values. Increase in cardiac output is due to: Increased blood volume To meet the additional oxygen required due to increased metabolic activity during pregnancy. Ref: Textbook of Obstetrics By D.C Dutta, 6th edn, page 53