[Amniotic band syndrome: pathogenesis, prenatal diagnosis and neonatal management].

Amniotic band syndrome is a collection of fetal congenital malformations, affecting mainly the limbs, but also the craniofacial area and internal organs. Two mains pathogenic mechanisms are proposed: early amnion rupture (exogenous theory) leading to fibrous bands, which entrap the fetal body; the endogenous theory privileges vascular compromise, mesoblastic strings not being a causal agent. The outcome of the disease depends on the gravity of the malformation. Termination of the pregnancy is usually proposed at the time of the diagnostic of severe craniofacial and visceral abnormalities, whereas minor limb defects can be repaired with postnatal surgery. In case of an isolated amniotic band with a constricted limb, in utero lysis of the band can be considered to avoid a natural amputation. However, as the exact etiology of amniotic band syndrome remains unknown and its natural course unpredictable, prenatal surgery continues to be controversial. Doppler studies of the constricted limb could be of useful predictive value of in utero amputation, and therefore could be helpful to determine when in utero treatment should be considered.