<prompt> Anencephaly can be diagnosed by USG at10-12 weeks of gestation14-18 weeks of gestation20-24 weeks of gestation24-28 weeks of gestation  <response>: A i.e. 10-12 weeks of gestation Earliest detectable congenital anomaly on USG is Anencephaly.Q Anencephaly can be diagnosed - Earliest at 10 weeksQ Best at 12 weeksQ 100 accuracy 