Upper limb abnormalities as an isolated ultrasonographic finding in early detection of trisomy 18. A case report

Trisomy 18 is the second most common multisystem malformation syndrome. We present here a case of a fetus with trisomy 18, in which upper limb reduction was detected prenatally, as an isolated defect, at 17 weeks of gestation. The pregnancy was terminated by vaginal administration of misoprostol, and postmortem examination confirmed the ultrasound findings, including bilateral upper limb reduction with radial aplasia, absent first metacarpal and thumb and ventrally hyperflexed hands. This case demonstrates the need for thorough ultrasound evaluation of the fetal hands, as early as possible, because upper limb deformities can be the only abnormality of trisomy 18.