12 week scan

[monal]

Hello,
I am confused about the dates I should be having my scan at. My doctor is counting from the assumed date of conception, two weeks after my LMP, and says I should have it mid-December which is "14 weeks." Is it supposed to be 12 weeks from conception, or 12 weeks from the start of my last period? My online date calculator thing thinks it should be between the end of November and the end of the first week of December.

And, also, is it going to make a massive difference?

Cheers.

Hi monal
Dates should be counted from first day LMP and not conception. The timing of your scan is important as it may affect whether they can do nuchal fold measurements . I'd ring the scanning department directly and explain your concerns or your midwife .

As the above poster says, it should be from your LMP. (e.g. I am 11w, which means the first day of my last period was 11 weeks ago, actual conception was probably around 9 weeks ago but no sure way of knowing).

According to the guidance on Mumsnet if you want the Nuchal fold measurements done: "The scan needs to be done between 11 weeks and 13 weeks plus six days gestation. Some hospitals will offer the test as part of your 12-week scan."

Having that part of the scan is optional though (you may wish not to know for whatever reason), but if you do want it, the date of your scan is important and definitely shouldn't be 14 weeks.

My 12 week scan is on monday which puts me at 13w5d, checked with midwife and she said it wasn't a problem. the only problem is in the last week I've really started to show so harder to keep a secret till then!

Thank you everybody. The receptionist was proper arsy about it and told me if the doctor said it was the right date then it was the right date. Then she said the conception date and the date of my last period was the same. Then she got a calendar out and agreed with me and my scan's on December 7th . I stuck to my guns.

And yeah, AlphaBeta82, I look very pregnant some days, when I officially tell people at work they are all going to say, "well obviously."

Well done monal. Receptionist obviously doesn't know her arse from her elbow if she thinks conception and LMP are the same thing..

Sounds like you got the result you need - eventually!

My 12 week scan is timed at exactly 12 weeks based on last period date, even though I have already had a scan at what I thought was 7 weeks, but was revised to 5 weeks. So by that dating when I turn up on Monday I will be 10 weeks, which is too early for the NT test. I just hope it means they ask me to come back in 2 weeks for another one rather than saying I've missed my chance for the NT test.

All fun and games! (And if I'm lucky it should mean I get 2 12 week scans!!!!)

Glad you got it sorted Monal.

Stuckinthefens. They will offer you another appt if you are too early for the nt scan. It happens very regularly with ppl not being totally sure of dates/ovulation etc. Even just 1 day too early matters. I'm suprised they've booked you for a scan when they should know you are only 10 weeks, unless it was at a diff hospital maybe?

Be wary if your scan is for 13+5. That's exactly when I went in and while it was within the proper time period, the baby wouldn't lie in the right position for her to take the measurement. And because they can't do it after 14 weeks I had to opt for the blood test instead. This was fine for me but may not be for everyone.

Good luck and let us know.

To clarify, I'm not sure how many hospitals offer you anothe appt if the measurement can't be done due to position etc rather than dates. Ours doesn't. Provided you are within dates you get one shot, they try everything within the half hour slot to get the measurement but if they can't get it then its just the blood test at ?16 weeks if you want it.

Not every PCT offers the nuchal - here we aren't offered one so they are fine to scan at 14 weeks. But we don't get a first booking appointment with the midwife until 12 weeks as so much can happen between the pregnancy test and 12 weeks that they don't need to see everyone in the end.

Once you get past the nuchal scan date requirement, it all gets a bit arbirtrary. I was induced at 40 + 11 days by the dating scan which was 40 + 22 days by the day of conception. Alas I couldn't convince anyone to take the early date so I ended up at home twiddling my fingers for 2 weeks before being induced...

Good luck op with your scan - I had mine

I've been redated back to 12 + 2days! So they could do a nuchal test but little one was not cooperative and wouldn't stay still enough in a position to allow measurement. There's no rescan offered - instead I just get a blood test at 15 weeks.

I had my scan today and weeblue you were right little one was a complete wriggler and took ages to get the measurements and pictures.

DH and I had some fun looking at pictures and guessing gender based on nub theory - if it has any credit to it must be a boy! ;-)