RUSSELL-SILVER SYNDROME - AN EXPLANATION FOR DISCORDANT GROWTH IN MONOZYGOTIC TWINS

Severe intrauterine growth retardation and suggestive dysmorphic and m alformation syndrome in 1 twin with a normal karyotype during a monozy gotic, monochorionic pregnancy led to the diagnosis of discordant Russ ell-Silver syndrome (RSS). Placental anomalies (velamentous cord inser tion, single umbilical artery, placental hypotrophy) for the small-for -date twins and a twin-twin transfusion syndrome confirmed at 21 weeks of amenorrhea suggest that early hemodynamic disorders may reveal or trigger RSS which has been considered to be of genetic origin. The pro gnosis for RSS is favorable, except for diminished adult size (less th an -2 standard deviations).