Amniotic band syndrome is a rare condition that occurs by chance in approximately 1 in 15,000 live births. It is believed that amniotic band syndrome occurs because of early rupture of the amnion, or one layer of the bag of waters that is closest to the fetus. The ruptured amnion then forms bands that cross the womb and can attach onto the body of the baby, thereby causing amputations, constrictions and/or other deformities. The cause of the syndrome is not known. The diagnosis of amniotic band syndrome is made during the pregnancy by ultrasound.
Some fetuses with amniotic band syndrome develop swelling of an extremity without evidence of amputation. The constriction results in marked edema and dysfunction of the extremity at birth. It is thought that fetoscopic (surgery using a scope placed into the womb) release of the amniotic bands could be of benefit in these cases. In utero endoscopic release of the constriction has been shown to result in restoration of the contour of the extremity and normal function after delivery. It is believed that in utero endoscopic release of the constriction may be able to avoid amputation of the extremity or prevent further neurological or vascular damage.
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