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18 Jan 2006

Down syndrome testing
Dear Doc

I am 10 weeks pregnant with twins (not identical)! We are over the moon. Went for a scan this morning and all looks well. Saw the spine,arms,legs,face, heartbeat etc, and they both moved!

The Dr is concerned because the one measures 9w 6days and the other one 10w 3days. He now wants me to go for Down syndrome testing in 2weeks time - just to make sure all is okay.

1. What could be the causes for the one being smaller than the other?
2. How do they test for Down syndrome?

I am trying to remain calm here, but can't help to feel concerned.

Answer 416 views

01 Jan 0001

A difference of 4 days at this stage should not be a cause for concern. Twins often vary in size anyway.
The test your doctor ha recommended is a nuchal translucency, which involves measuring the thickness of the neck folds. This gives an idea of the risk for Down syndrome.

Best wishes
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