can you only have the ultrascreen in the 12th week?

if so, why? just wondering because i'm scheduled for my u/s next week when i'll be 12w6d but might need to reschedule because of work. obviously if it can only be done in your 12th week i wont reschedule, but for my own peace of mind, why do they do it in the 12th week?

Re: can you only have the ultrascreen in the 12th week?

Bewteen the 11th and 13th week; the calculations for the risk will be off otherwise.

If you miss the ultrascreen the next 'chance' to calculate the genetic risk will be your AFP (done between 15 and 17 weeks). This does not include a sono like the ultrascreen does - it's just a blood test.

Re: can you only have the ultrascreen in the 12th week?

i went at 11w5d

Re: can you only have the ultrascreen in the 12th week?

I went at 13w1d and it was perfectly fine

Re: can you only have the ultrascreen in the 12th week?

Re: can you only have the ultrascreen in the 12th week?

I did it at 11 weeks 1 day. They said to do it between the 11th and 13th week or else the results are not accurate.
When you call up to reschedule I would stress to them your due date and how far along you are so they schedule it at the proper time.