Malrotation is a birth defect caused by the incorrect positioning of a fetus's intestines in the abdomen while the fetus is still in the uterus. Malrotation can cause sudden twisting of the intestines.

Most infants with malrotation develop symptoms during the first month of life. Symptoms include:

• Vomiting of blood or yellow or green liquid (bile).
• A swollen, painful abdomen.
• Poor feeding.
• Weight loss.
• Crying and fussiness.

It is a medical emergency if an infant is vomiting blood or green liquid.

If malrotation of the intestines causes symptoms, surgery usually is required to correct the position of the intestines. Malrotation doesn't cause symptoms in all people.