Anatomical closure of ductus aeriosus occurs at ________: (A) Bih, (B) 3-4 days, (C) 10-21 days, (D) 10-15 hours
Answer is C. Ductus aeriosus is functionally closed at 10-15 hours after bih and then anatomical closure occurs at 10-12 days. Ref: Ghai essential pediatrics 9th edition Pgno: 400