Males are more commonly affected than females, with firstborn males affected about four times as often, and there is a genetic predisposition for the disease. It is commonly associated with people of Scandinavian ancestry, and has multifactorial inheritance patterns.<unk>  is more common in Caucasians than Hispanics, Blacks, or Asians. The incidence is 2.4 per 1000 live births in Caucasians, 1.8 in Hispanics, 0.7 in Blacks, and 0.6 in Asians. It is also less common amongst children of mixed race parents. Caucasian male babies with blood type B or O are more likely than other types to be affected. Infants exposed to erythromycin are at increased risk for developing hypertrophic<unk> , especially when the drug is taken around two weeks of life and possibly in late pregnancy and through breastmilk in the first two weeks of life.
Pyloric stenosis
Gastroesophageal reflux disease
Retained antrum syndrome
Intussusception (medical disorder)
Gastric volvulus
Esophageal achalasia
Hiatal hernia
Atresia