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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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HIV transmission to the fetus from mother occurs most commonly at what gestational age?
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The correct answer is  Virologic analysis of aborted fetuses indicates that HIV can be transmitted to the fetus as early as the first and second trimester of pregnancy. However, maternal transmission to the fetus occurs most commonly in the perinatal period. Studies indicate that the relative proportions of mother-to-child transmissions were 23-30% before birth, 50-65% during birth, and 12-20% via breast-feeding.