Due date differences

[georgee]

Hi

The difference between the due date that I've been given and what I think my due date is, is 9 days. This means that I'm 40 + 5 according to them, and 39 + 3 according to me. It's all been OK so far but of course now the 'due date' has passed we're getting to talk of induction/compromising health of the baby if she's left in there too long, and we're running into difficult decisions.

I was two weeks late and so was my DH when we were born, so I'm certainly not expecting this one to come on time. It's my first.

I just want the baby to come out when she's ready. Any tips for managing this situation or do you think I should just go for their dates and get induced when they recommend?

Thanks!

When you are invited to induction meeting, tell them you are sure of your dates and so are only 39+3. My birth plan said I would agree to induction when 14 day past MY estimation of the date.

Is the 39+3 based on LMP or ovulation, if LMP how long are your cycles? When was the 40+5 due date established? If it was at a 12 week scan it can be up to a week "out" - scans only accurate (to nearest couple of days) if done at around 7 - 8 weeks.

You don't HAVE to be induced, can say that as you are not late based on yoru dates, should not be any risk to baby but to be sure you'll agree to scans/monitoring.

Thanks for responding MumNWLondon - my guess is based on my LMP and the fact that my cycles are pretty much bang on 28 days. Their due date was established at the 12 week scan but (and this sounds bonkers) both DH and I have quite long torsos (and short legs!) so if they're basing the baby's age on torso measurement, I wondered whether the baby was just a bit long in the torso, rather than as old as they thought?

I would be very happy to undergo regular monitoring when it's getting late (in their eyes).

How different was your estimation of dates and did you go past their recommended induction date in the end?

Do you know when you typically ovulate? Although a 28 day cycle definitely doesn't mean you ovulate on day 14 (as is assumed), it would seem strange to ovulate on cycle day 5. Do you know how long your last period was? If you period only finished the day before they're saying you ovulated, it would seem that something is wrong in their measurements. If your period was 5 days long or longer, then no way would you have ovulated when they think you did.

I'm pretty sure that the dating scan works on the assumption that up until 13+6, human babies develop at the same rate. I'm not sure how accurate that is though. I know that my dates changed by 5 days from a 8 weeks scan to a 12 week scan! So there must be some margin of error.

Hi japhrimel - I'm pretty sure I ovulate mid-cycle from the signs, although there's always a possibility that one slipped through early! We have non-identical multiple births in the family which might indicate weird ovulation patterns or ovulating more than once a month! That last period was a normal one - ie I would still have been going on day 5, albeit lightly!

Thanks for letting me know what happened with you - it's obviously not completely exact.

Interesting about the torso point! I also have a week's difference between what the scan I had at 10+3 (by their date) or 11+3 (by my date) said and my own dates, and I also have a long torso and short legs (have you also got a not huge bump as it has more space to go up and down rather than out?). As the baby was too small at that first scan to do the nuchal measurement I had to go back at 13+6, by which time the baby was a fair bit too big for the nuchal test, hence why I think my date was more accurate.

Hi Emster - you'd think I'd have been able to absorb the bump size into longer-than-normal torso but actually it's pretty large even so and sticks out a lot! But that's just recently and I am at term now - it was nice and neat for quite a while. Interesting to hear your experience too.

I had scans at 6 weeks and 10 weeks and my EDDs from these varied by 5 days. The earlier (and more accurate) scan tallied with the date my LMP gave.

Scan dates are not acurate to the day (estimated). They can be +/- 5 days either way. What wasnt agreed when they designed the paperwork for EDD was it could of been "the week of" but that would of made it more difficult to design so they worked on 1 day. Actually my dates and the scan dates were only a few days out however I had to be induced twice.

I also need to point out (after all the studying I did for my VBAC - which i didnt get) not all babys are due at 40 weeks. Some are 42 weeks and I question the pressure on mums-to-be to produce within this time to me its a waste of resources and increase in induction which lead to more c-sections.

I also here that many babys happily arrive at 43 weeks. If I had my time again I would have not of been pushed into it (leading to 2 emcs) You can get a scan done to check if there are any problems around 42 weeks.