# first trimester screening for down's



## hoping2 (Jul 24, 2010)

Dear Emily, I've just had my 12-week scan. I'm pregnant with twins. Twin 1 has a combined risk of 1:153 and twin 2 has a combined risk of 1:134. I'm pregnant from donor eggs and the donor was 22. The nuchal folds for twin 1 were 1.3mm and for twin 2 1.5mm. My blood test came back as a 1 in 30 chance of down's. Can you tell me, are the blood test results very reliable? The nuchal folds measurements seem very good. Should I have a repeat blood test by next week (week 14)?

Thanks, Hoping2


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## emilycaitlin (Mar 7, 2006)

Hi,

The last statistics I heard were that these tests on a singleton pregnancy were 85% accurate, however I don't know the statistics with twins. It is a relatively recent thing that bloods can be done for screening with twins. Have you seen an ante natal screening midwife? They are the best people to give you advice as it is a specialised midwifery area and they have specific in depth training. If it's not possible, let me know and I will try to find out for you,

Emilycaitlin xx


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## hoping2 (Jul 24, 2010)

Dear Emily, thanks for your message. Yes, I've spoken to an antenatal screening midwife on the phone and am seeing a consultant next week. I know from researching online that some clinics don't use the blood tests for twins as they don't think they're accurate enough. I'm a bit unsure about what to do. But thanks for your help. Best wishes, hoping2


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## emilycaitlin (Mar 7, 2006)

Hi,

The tests that there have been till now weren't accurate with twins, but the new ones that have come out in the last couple of months are much more accurate than they were,

Emilycaitlin xx


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