Amniotic band syndrome (ABS) is a rare congenital disorder that results when the amnion, part of the fluid-filled sac around the baby, is damaged. This produces bands, or fibers, that can wrap around or trap parts of the fetus, decreasing blood flow to those areas. Hands and fingers are the most common body parts to be affected by ABS, but it also may damage the face, legs or toes. Effects can range from slight creases in the skin to severe limb deformity or amputation. ABS is one of the main causes of club foot. Since the bands are slender, ABS often is difficult to diagnose by prenatal ultrasound. Most cases are found at birth.
Treatment for ABS depends on the extent and location of the bands. Sometimes surgery is attempted shortly after birth; other times the doctor will advise waiting several months. In severe, rare cases, fetal surgery to remove the bands is an option.