<unk>  occurs in around 1 in 3,000 births in the United States. The most common form of<unk>  is duodenal atresia. It has a strong association with Down syndrome. The second-most common type is ileal atresia. 95% of congenital jejunoileal obstructions are atresias; only 5% are stenoses. Prevalence of jejunoileal atresia is 1 to 3 in 10,000 live births. It is weakly associated with cystic fibrosis, intestinal malrotation, and gastroschisis. The frequencies of each type from Louw and Barnard's classification are as follows: * Type I: 19–23% of cases (mean: 20.6%) * Type II:10–35% of cases (mean: 25.3%) * Type IIIa: 15%–46% of cases (mean: 30%) * Type IIIb ("apple-peel" type): 4–19% of cases (mean: 8.8%) * Type IV: 6–32% of cases (mean: 15.9%). (Note: the mean percentages total higher than 100% due to rounding.)
Intestinal atresia
Gastric atresia
Duodenal atresia
Gastroschisis
Choanal atresia
Situs inversus
Familial multiple intestinal atresia
Atresia