12 week scan changed due date to an impossible date - worried about impact on C-section timing

[duedateworry]

I tracked my cycle with LH strips, which pinpointed the LH peak / day of ovulation. Once pregnant, I had my HCG tested at 11, 13 and 15dpo. The results were exactly in line with what they should have been on those days.

At my 12 week scan, the due date was changed to be four days earlier.

This would mean I ovulated on CD8(!), and days before getting an LH peak. It also means that the HCG results (which they’re now saying were taken on days 15, 17 and 19 dpo), would have been completely out of sync with what they should have been.

I know the date they’ve given me is wrong and I’m worried that the c-section I need to have will be set for a date four days too soon.

Has anyone had any joy in getting the NHS to change a due date that is patently wrong?

Later scans will confirm, wait til 20 weeks, mine changed.

Will you be having a section at 37 weeks? If not, 4 days won't make a difference, they are happy as long as baby is 37 weeks.

I had the same btw, I was tracking ovulation so knew when I conceived yet they moved my date as though I was 5 days further along. Think it's quite normal!

My 12 weeks scan put my ovulation date on CD5, I know that I ovulated on CD11. I will opt for an elective c-section. I think it’s fine, there will be more measurements. And often the NHS c-section dates are on the late side anyway due to availability issues (my friend’s kept being pushed back, should have been at 38 weeks but she was 39+1 in the end).

@spannered Usually a c-section is booked at 39 weeks of pregnancy. Babies born earlier than 39 weeks are more likely to need help with their breathing. So yes, if they’re saying I’m 39 weeks but I know I’m 38w3d then there is an issue there.

There is absolutely no issue with baby being born after 37 weeks... Hence why it's called term and then full term at 38 weeks. My son broke my waters naturally at 37+5 and we went home a day after he was born. only staying overnight as it was 11pm by the time we left the delivery ward. He's now 5, big for his age (height) and very healthy.

I've also never known a pregnancy to date exactly as ovulation etc predicts. My babies are always 'due earlier' by atleast a week if you rely on ovulation tracking. That would mean in your eyes, my son was born at 36+5 but he wasn't lol, he was also 7lb latched immediately and breathing perfectly fine. The tracking is not an exact science, nor does every baby grow and develop at the same rate.

I knew with my first that as we'd only had unprotected sex on one date, that conception could only have been around certain dates. Dating scan moved my dates forwards by 2 weeks. DD was an ELCS too, at 38+6 (their dates). She was small (i think far too early) but she was absolutely fine and is at school now, very happy. I did mention to midwives during the pregnancy but they seemed to view it as completely normal.

Anything after 37 is highly unlikely to need additional help. That's not even considered premature.

I had similar. My dates got changed and I was a bit wtf, but they changed a few times in the pregnancy I think.

My DC2 was an elc at 39 weeks and she was definitely less ready (in my opinion) than my DC1 who was born v similar point. Honestly I don’t think it’s an exact science at all!

DC2 is now 6 and is perfectly healthy and that few days made zero difference

I had similar and was due around Christmas and obviously they don’t schedule sections for Christmas Eve or Christmas Day so was moved those extra days earlier on top of the dates mismatch, so somewhere around 38w4d; didn’t even think about it tbh, and it was totally fine. DS was definitely sleepier and hairier and smaller than my 42-week beast but health-wise there was no material impact. It’s a matter of days and 38 weeks+ is well cooked.

I had my girl at 37+4 (but I was actually 36+6) and they weren't concerned at all as she was past the 37 week mark. We didn't have to stay and she didn't need any additional support.

If your section will be booked for 39 weeks, your baby will be well past the time for concern.

I did raise the date issue at my 20 week scan but they said that they don't change the date as the 12 week scan is more reliable than the 20 week scan in terms of dating a pregnancy.

There won’t be any issue at 38 weeks. My planned c section was for 39+ 4 so you might not even be too early anyway

It'll be fine having it in the 38th week.

Fwiw, I knew my dates were out by a week. When I booked my elcs, I requested that it be for 40+0, which it was, so that my elcs would really be in week 38. You don't have to accept the day they give you. As it happened, I went into labour in my 38th week anyway!

My recent was born naturally (wanted a c section, but that's a long story) at 37wks dead on according to dates from scans. He was absolutely perfect apgar of 9. He did have jaundice, but that's unrelated.

Midwives did say one day earlier, and he would have been nicu for observations. They also reminded me that your EDD is just that an estimate. Mine could well have been premature or even 37 wks plus 5.

If I went by my dates, I would have been 5 wks earlier. But clearly, baby was what they expected for 37wks.

Depending on whether you are low vs high risk you may also have additional scans.

Trust me they won't deliver your baby earlier without very, very good reason to. And, if they need to they will give you a steroid injection for baby's lungs.

10m ish on and baby has nearly quadrupled in weight and is off the charts for length. Perfectly healthy and mobile!!!

It really doesn’t matter. And the window for implantation is 7-12 dpo so of course the dates at 12 weeks will not exactly match ovulation.

Please don’t worry too much about this, I’ve had a baby at 37 and 38 weeks both c sections and they didn't need help with their breathing.

The scan works based on your last period and the size of the baby when measuring. They give an estimated due date but many other things can impact the timing of the arrival.
Please try not let this worry you too much as the midwives will look after you. Your c section will be scheduled for the correct time. Your c section can also take place beyond 39 weeks such as 39+4 etc, they just aim to do it before 40 weeks.

I just had my dating scan and baby was measuring 13+1, 13 and 12+6 all at the same scan. It was different every time he measured as the baby was moving and he said its as they stretch / hunch up and even just 1mm can change the date so I wouldn't think too much into dates. I was meant to be 12+4 as well so got dated a little ahead and I knew when I ovulated etc

I don’t think it will make that much difference.
But also they only set the date like a week or two before usually, so they’ll have done further scan/s before then. Don’t worry too much at this point. Are you consultant lead/shared care? If so you can chat to them about it then. I’d be more worried about it the other way around to be honest.

You're worrying needlessly. Try to relax and enjoy your pregnancy.

I wouldn't worry too much about this OP a few days won't make much of a difference after the 37 week mark.

Youre also not guaranteed a section at 39 weeks or even to have it the day they booked you in (depending on how busy they are with emergencies).

You have to learn to go with the flow a little or you will be a stressed out wreck before baby even appears and that's not good for either of you.

Good luck with everything and congratulations!

You don't need to worry about this. I knew my 12wk scan dates were not quite 'right' because I had blastocysts implanted on certain days and knew exactly to the minute how long they'd been in there! My 12wk scan shifted things a few days due to the rate the babies grew at. They all came out via C-section at (approx) 39wks, massive, healthy and happy.

Many factors can affect the health of a baby growing and delivering, not just being a few days before 39wks.

Mine was IVF we knew to within a 14 hour window when fertilization occurred. We were still given a date 5 days different at the 12 week scan. A matter of days at 39 weeks won't have any impact on your babies health.

Is this your first ? In the nicest possible way you need to chill out a bit. You are 12 weeks and you are worrying about c- section dates ? 4 days is nothing it will make no difference at all. You may not need a section baby may decide to come at 28 weeks. Literally any thing could happen.

Due dates vary like this; they know it’s not an absolute. You can argue for a c section slightly later though if you feel strongly, it’s arguing for an earlier one that is much harder.

C sections are usually booked for in the 39th week. Very rarely bang on 39, my trust only does electives 2 days a week. It shouldn't make a difference.

I had ivf. Absolute certainty about my dates! Still had my due date moved. I would not worry.