Hi bugalug

It is all very confusing. The 12 week scan SPECIFICALLY checks for Downs because some women (especially older mums like me) are higher risk than younger mums like yourself. As someone has said, you have a pretty low risk on your age alone of having a child with Downs.

Having said that, the 20 week scan will check for physical abnormalities - some of which would be 'fixable' ie. like something wrong with the intestines, heart, lungs etc whereas obviously Downs is something that isn't 'fixable'.

So don't be too freaked out by the word 'abnormalities'.

So at your 20 week scan they won't SPECIFICALLY be checking for Downs whereas they would at the 12 week one by looking at something called the nuchal transparency. Now I don't know whether they can still do this at your 20 week scan if you ask for it or not. Obviously they can take any measurement they like but at 12 weeks they are able to compare what that measurement would be for a child with Downs as opposed to a child without Downs. Later on, perhaps that difference is not as pronounced - not sure.

My ob also told me that if you do have a baby with a chromosomal abnormality like Downs, there is usually some other physical characteristic that is picked up at the 20-week scan that would also be an indication eg. a hole in the heart.

I'm sure it's not too late to run some tests if you are concerned though your risk is low. Perhaps just ring your doctor and have a chat - I know what you mean, sometimes we read too much and we end up more confused!