<unk> s are often discovered before birth; either during a routine sonogram which shows a dilated intestinal segment due to the blockage, or by the development of polyhydramnios (the buildup of too much amniotic fluid in the uterus). These abnormalities are indications that the fetus may have a bowel obstruction which a more detailed ultrasound study can confirm. Infants with stenosis instead of atresia are often not discovered until several days after birth. Some fetuses with bowel obstruction have abnormal chromosomes. An amniocentesis is recommended because it can determine not only the sex of the baby, but whether or not there is a problem with the chromosomes. If not diagnosed in utero, infants with<unk>  are typically diagnosed at day 1 or day 2 after presenting with eating problems, vomiting, and/or failure to have a bowel movement. Diagnosis can be confirmed with an X-ray, and typically followed with an upper gastrointestinal series, lower gastrointestinal series, and ultrasound. Classification Sites of small bowel atresia: duodenum,alt By location<unk>  may be classified by its location. Patients may have<unk>  in multiple locations. * Duodenal atresia – malformation of the duodenum, part of the intestine that empties from the stomach, and first section of the small intestine * Jejunal atresia – malformation of the jejunum, the second part of the small intestine extending from the duodenum to the ileum, that causes the jejunum to block blood flow to the colon * Ileal atresia – malformation of the ileum, the lower part of the small intestine * Colon atresia – malformation of the colon Malformations may also occur along multiple portions of the intestinal tract; for instance a malformation that occurs along or spans the length of the jejunum and the ileum is termed jejunoileal atresia. By malformation<unk>  can also by classified by the type of malformation. The classification system by Bland-Sutton and Louw and Barnard (1955) initially divided them into three types. This was later expanded to five by Zerella and Grosfeld et al. Type I In type I, there is a wall (septum) or membrane at some point in the bowel, leading to dilation of the bowel on the nearer side and a collapse of the bowel on the latter side. Bowel length is not usually affected in this type. Type II In type II, there is a gap in the bowel, and either end of the remaining intestine is closed off and connected to the other by a fibrous cord that runs along the edge of the mesentery. The mesentery remains intact. Type IIIa Type IIIa is similar to type II, but the mesentery is defective (there is a V-shaped gap), and the bowel length may be shortened. Type IIIb In type IIIb, also known as the "apple peel" or "Christmas tree" deformity, the atresia affects the jejunum, and the intestine is often malrotated with most of the mesenteric arteries absent. The remaining ileum, which is of varying length, survives on a single mesenteric artery, which it is twisted around in a spiral form. The term apple-peel<unk>  is generally reserved for when it affects the jejunum, while Christmas tree<unk>  is used if it affects the duodenum. It may affect both, however. Type IV Type IV involves a combination of all the other types and takes the appearance of a string of sausages. The length of the bowel is always shortened, but the last part of the ileum is usually not affected, as in type III. This type usually affects the nearest end of the jejunum, but the far end of the ileum may instead be affected.
Intestinal atresia
Gastric atresia
Duodenal atresia
Gastroschisis
Choanal atresia
Situs inversus
Familial multiple intestinal atresia
Atresia