Booking in with midwife

[brodiee]

Is it true that they assume a 28 day cycle for all women and use the 28day wheel thing to calculate due date?

I have a ds and when I had him I had approx 27/28 day cycles so everything worked out.

I had a mc earlier in the year and after that my cycles were 24 days. Starting taking pregnacare conception and it extended my period by nearly a week and then delayed ovulation by a week. Then I got a bfp. So that cycle was like 32 days long.

If I was to tell midwife first date of last period (21 June) she will assume due date 28 March. However I was using ovulation kits and know i ovulated a week late on 12 July.

Working out due date from ovulation this would mean due date 4 April. A whole week later.

Is it worth just saying I can't recall first day of period but know when I ovulated? I've heard stories of midwives ignoring individuals cycle lengths if not '28 days' and therefore calculating incorrect due dates

We didn't know our dates at all as were on the contraceptive pill with no periods. I just said I didn't know and then we had a private scan to find out how far along we were..... could try that option if you can then you'll know for sure?

A week wont really make much difference at this stage. They will date your pregnancy from the 12 week scan and go by that

I think they do, but they might adjust according to your scan anyway.

My first, they changed my due date to 4 days later than what my LMP date would have made it.

They should adjust due date by the dating scan if it's found to be a week out.

If it particularly bothers you the other choice would be to lie and add 7 days onto your previous period date since you know exactly when you ovulated.

They’ll go by the 12 week scan so don’t worry about it too much. They’ll only use the LMP EDD to work out roughly when you need a scan.

They only fill in EDD once you've had the dating scan so don't worry.

They won’t give you an official due date until the dating scan at approx 12 weeks (precisely for this reason). I have long cycles and always knew my due date wouldn’t work out right when using LMP. It was always pretty much what I expected after the dating scan though.

Ok thanks. I just don't want them to stick by the due date at booking if I give lmp date as could possibly mean they think I'm an extra week along at the end of the pregnancy and I want to avoid induction.

Also worried that they could end up giving me my 12 week scan a week or two early if they use lmp for due date.

I was high risk for Down's syndrome with my son after my 12 week scan and I'm particularly anxious about this stage.

If I was to get a scan at 10 weeks when they thought I was 11, would the nuchal measurement and test still be able to be done?

If they send you for your 12 week scan too early they will arrange another for the following week so they get an accurate nuchal food measurement. It’s happened to me twice!
They won’t stick by your LMP due date, that’s the point of the dating scan really. Very few people have a 28 day cycle, and obviously people all ovulate at different times/implantation takes different times. LMP is a ‘best guess’ scenario and then the dating scan gives a more accurate view. My cycles were anything from 26 days to 45 days with DD1.

I had very long cycles (45 the cycle I conceived) but midwife wouldn’t take ovulation date only lmp. It just meant I had two scans-one at what midwife believed to be 12 weeks where they couldn’t get all the measurements because baby was too small and the other at what was actually 12 weeks where they could.

I had the same problem and was worried they’d sent me for my scan to early, however although I also knew when I’d ovulated my dating scan dated me at 11+6 when I was convinced I would be more like 11+2. Knowing when you ovulated still doesn’t mean you can predict the EDD really as you don’t know when implantation occurred. If they can’t get the measurements then they’ll just give you another appointment to go back the following week. Better to go too early than to late in my opinion.