OEIS complex (omphalocele exstrophy imperforate anus spinal defects) in monozygotic twins

The omphalocele-exstrophy-imperforate anus-spinal defects (OEIS) complex is a consistent and recognizable pattern of midline abdominal and pelvic defe cts. It is rare, affecting 1 in 200,000 to 400,000 pregnancies and is even rarer in twin gestations. This is arm autopsy study of OEIS complex in mono zygotic twins after pregnancy termination at 20 weeks of gestation. Unremar kable family history but concordance of monozygotic twins for the defects m ay support the theory that early malformation complexes, e.g,, OEIS, and mo nozygotic twinning are manifestations of the same disturbance of early blas togenesis. (C) 1999 Wiley-Liss, Inc.