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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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Chorionic villous sampling is needed in all except
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The correct answer is  Chorionic villous sampling(CVS) is done at the 10 - 13 week of gestation to diagnose conditions which could be debilitating or life threatening for the unborn fetus. Neural tube defects are best assessed at a later gestation around 20 weeks though the earliest to be picked up is ANENCEPHALY which can be picked up by 10-12 weeks with USG. The most specific indicator for Neural tube defects is the acetylcholinesterase