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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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The MOST common cause of vaginal bleeding in a neonate is:
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The correct answer is  Neonatal vaginal bleeding is caused by maternal hormone exposure during pregnancy. These maternal hormones are abruptly withdrawn at the time of bih. It is entirely normal and presents soon after bih as a 'mini period' in females. It will resolve, usually lasting less than a day, and is painless. Ref: A Practical Guide to Pediatric Emergency Medicine: Caring for Children in ... edited by N. Ewen Amieva-Wang, 2011, Page 333 ; Shaw, 13th ed, Page 48