C354 Normal Development, Structure, and Function of the Stomach and Intestines C355 Pyloric Stenosis and Other Congenital Anomalies of the Stomach Hypertrophic pyloric stenosis ?? ????? Epidemiology Symptoms usually develop between the 2nd and 7th week of age (rarely after the 12th week). Etiology Environmental factors Exposure to nicotine during pregnancy Infants who are bottle-fed tend to consume a larger volume in less time compared to infants who are … Continue reading S4 Stomach and Intestines