Limb reduction anomalies and early in utero limb compression.

Seven instances of limb reduction defects are reported with a presumed common underlying etiologic theme of early in utero limb compression, deduced as being due to a bicornuate uterus in four instances, a large fibroid in one instance, and early amnion rupture with transient amniotic fluid loss in two instances. Similar types of limb reduction defects have been experimentally produced as a consequence of early withdrawal of amniotic fluid with resultant compression of the developing limbs, leading to vascular disruption. A similar mechanism is hypothesized to have caused these seven instances of limb reduction defects.