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Accurate and Simple Evaluation of Vascular Anastomoses in Monochorionic Placenta using Colored Dye
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Published on: September 5, 2011

Down syndrome in monochorionic twins

I L Sin1, T Y T Tan

  • 1Raffles Women's Centre, Raffles Hospital, 585 North Bridge Road, #12-00, Singapore.

Singapore Medical Journal
|August 1, 2009
PubMed

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.

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