This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
Vomiting on the first day of baby's life may be caused by all of the following except – 
Select and explain. 
A. Pyloric stenosis, B. Oesophageal atersia, C. Aerophagy, D. Amniotic gastritis
A: Pyloric stenosis
Answer: A: Pyloric stenosis 
Explanation: A large number of normal babies vomit on first day due to irritation of stomach by swallowed amniotic fluid
The regurgitation / vomiting in a neonate is due to -> faulty feeding techniques or, aerophagy
Eosophageal atresia may present with vomiting on the first day.
In hypertrophic pyloric stenosis vomiting characteristically occurs after 2 weeks of age. (2-3 weeks).