title: Down syndrome in monochorionic twins.
abstract: Down syndrome in monochorionic twins has rarely been reported. We report such a case diagnosed prenatally. Maternal serum screening was performed at 15 weeks for a twin pregnancy which indicated a risk of greater than 1:50 for Down syndrome. The review of early ultrasonography confirmed monochorionic twins. Amniocentesis at 17 weeks' gestation was performed on one of the twin sacs, which confirmed Down syndrome. A screening scan at 19 weeks' gestation showed isolated absent nasal bones in both twins. Termination of pregnancy was performed subsequently.
authors: Raffles Women's Centre, Raffles Hospital, 585 North Bridge Road, #12-00, Singapore.
authors: I L
authors: IL
authors: Sin
authors: T Y T
authors: TY
authors: Tan
mesh_terms: D000328:Adult; D000649:Amniocentesis; D000650:Amnion; D002823:Chorion; D004200:Diseases in Twins; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis; D014430:Twins, Monozygotic; D016216:Ultrasonography, Prenatal