Due Date - Interesting fact from my Ob.

I am now overdue by about 9 days according to my due date and was meant to be induced today but decided against it. Waiting for baby to come naturally with support from our Ob. (provided he comes by Monday 17th otherwise we have agreed to induce).

When we had our appt yesterday I had reviewed my dates from basal temperature monitoring and discovered that my due date is more like 9 May rather than 3 May. I spoke to the Ob. about it and he told us that unless there is less than five days difference in dates (even when baby is an IVF baby and they know the exact date of conception) they use the ultrasound measurements and dates derived from this to determine the due date.

I didn't want to spend my whole appt discussing why this was so can't say any more but I was surprised by this fact.

It's normal but very frustrating! Dd1 was born at 34weeks when I thought she was closer to 36 going by my cycle. Our peadatricion agreed he said she didn't look or act like a 6 week premmie, she was closer to 4 weeks because she was such a fighter and got home in three weeks. He expected her to be in hospital for longer.

The ultrasound moved my date again with dd2 she almost arrived at 35 weeks but I thought I was further along. The same has happened again, so we are planning for a third early arrival. In my case it gives me a little bit more time before they intervene but I don't trust the early scans, I was charting with the first two so I knew when I had ovulated too.

Of course its fact because it came from a man with a medical degree ;) Seriously though, it might be 'fact' that they use an u/s machine to estimate dates, but from a biological point of view, it means nothing. Size means nothing in relation to due dates so the u/s is really quite pointless IMO. This is why they say a 'normal' pg is anything between 37 to 42 weeks and I reckon that those women who have their bub induced at 42wks and out comes a baby still covered in vernix and a perfect placenta could probably go for a lot longer yet iwthout drama. Being pg and giving birth is the work of mother nature and she isn't exactly an exact science ;)

Just want to say well done for waiting :) I have had three births and one was artifically induced due to being past due date by 10 days. My baby showed no signs of being over cooked at all... placenta ws in good condition etc.

I had heard of the measurements thing being important but have always wondered if they take genetics into account... say the dad was really tall/big and he wasn't present... does this mean they would expect bub to arrive earlier if bub had his genes? My DH is on the smaller side for a guy... lucky i at least had that in my favour if they ever took measurements into account. 2 of my pregnancies were technically overdue... I think length can depend on the woman just like some women have longer menstrual cycles. My third baby was induced at 37 weeks... and was 9 pounds! you never can tell sometimes!

good luck! Hope you start naturally... it really is a much better way to do it... from my experience.

Your own, unique cycle dates are way more accurate than mathematical averages - who is average and how can a computer tell us! The fact that only 3-5% of babies come on their due dates is testament to this. Anyway, no matter what, it's your body and your decision to make. He may try and pull rank, but he can't force you, it's against the law. Follow your instincts, trust your body and your baby. :) Also the later the scan the less accurate it will be, genetics takes over. Takes a big baby and a small baby to make an average baby - so forcing them all to be average just doesn't gel well with these little beings.

well obviously someone with a medical degree and a machine that goes ping knows better than the mother!
It's probably a good reason not to have an early scan if you know your dates.
I hope you can beat the induction - not nice! Maybe you can mention to your OB that the average gestation for first time mums is about 41+ weeks... so you're actually only just post-dates now anyway.

I agree with regards to baby knowing best & wondering how it is a scan can be more accurate then an actual date - it doesn't make a great deal of sense to me.

I have great respect for my Ob. & he has been very respectful of my wishes and I understand his view is a medical one & I guess that is why we engaged with him in the first place. I do my research, discuss with my DH, we make a decision & have a fall-back if we think we need one & then we discuss with the Ob. Sometimes I think I am the most opinionated & strong minded patient he has (since my appt's take between 15-30 mins and just about everyone else takes about 5 mins...although they might not be first time Mums so they may not need to discss so much). He is always willing to give me the time I need and explains the benefits & risks from his persepective but allows us to make the decision.

Odd. IVF pregnancy here, and even though scans at times disagreed, they ALWAYS took my IVF dates as being exact. I guess different doctors do different things.

BW

well i just recently booked into the hospital im having this baby at and they were going to take my u/s details but apparently the ultrasound was only accurate to + or - 5 days so they took my dates lol so they cant really be too accurate can they

My EDD from scans actually matches my calculated dates from LMP and ovulation... I think only one scan was different by 3days and my OB was happy to take my date

At the hospital I went to they said you "had" to change your due date if the scan was 7 days or more different, so 2 days more than your OB's 5 days. My son measured 6 days ahead so I said I'll keep my original due date thanks (to avoid inductions) and they had to think about it before saying, yep, that was within their "rules".

Prior to having DD I worked in perinatal trials and the rule we used was there had to be more than 10 days disagreement between LMP and u/s dates for us to use the u/s over the LMP (don't collect ovulation dates). Also, we only used the u/s if it was done at <24 weeks. As far as I know this is the same rule the OBs involved in the trials unit used in their practice.

Your OB sounds reasonable letting you make your own decisions. Good luck. I hope you beat the induction.

I only wish we had looked at the dates again before we came so far. Even though I know that I am only five days over 40 weeks because I have been looking at 3 May as my due date for so long I think I have brainwashed myself into believing this date - I actually thought that the 3 May was my date as we have three dates written on our ante-natal record (24/4, 3/5 and 9/5) then when I rechecked it wasn't; it was the date they provided at the NT scan & for some reason I took this on board as the due date.

Funny thing I remember when I was having the NT scan the woman doing the scan asked if we had had a dating scan & I said no, we knew when conception was so we didn't think we needed one. She must have done it then.

I am not usually so easily hoodwinked but the NT scan was a very anxious time for us as this was the time in my two previous pregnancies that we found out our babies had died. I can only think I (we) were so overwhelmed by the heartbeat and good results that we weren't focusing on the dates. On top of that I was very very sick & on the verge of being admitted to hospital so there was a lot going on.

It is good that I did look though before any decisions were made around the date....phew!

i know the feeling of confusion hun, last week my docs realised that they have 3 due dates for me, and they are 4/6, 11/6 and 18/6!!
we had been going with 18/6 but then saw that this was the dating scan, with my dates from my cycle my due date is 4/6. im not really complaining too much as this gives me a greater window before they start wanting to induce me for being overdue but still really inconvenient!!

hope u avoid induction, it would be much better to let bubs decide when to appear!