Which is my due date?

This pregnancy was very planned, so I knew exactly what my dates were. (LMP etc) .
The 1st scan I had at 13 weeks was a nuchal scan and this was how we found out we were having twins! Talk about an OMG moment!

Since then I've had monthly growth scans and these indicate that babies are 5-6 days ahead. My questions is, what do I consider my due date? I am 100% certain of my dates and so am inclined to go with thoses dates. That would put me at 26 weeks & 2 days.
On the other hand, I also know that I ovulated on day 8-9 instead of the 'average' day 14, which would account for the 'extra' growth, making 27 weeks & 1 day right.

Doctors/radiologist say different things.

My main concern witht this is that as I'll be having a c/section, I don't won't the babies to be out earlier than they have to be. Plus it makes it confusing to remember what I'm up to!

 

usually if the scans are consistent, they switch your due date to your scans, regardless of if you were positive about your dates. i had an IUI with mine, but they still redated me according to the first scan.

 

If you know when you ovulated, then calculate your due date from there (there are tons of due date calculators online that will calculate your due date based on ovulation date). Our twins have always measured about a week ahead, but my doctor never changed my due date because we know exactly when I ovulated, based on all my charting etc. I would insist on using your due date based on ovulation etc because the scans can vary to some extent, but if you know for sure the date of conception that's a little more concrete. And I agree that you want to be more certain how developed they are for a c/s. afterall a week can make a difference.

As an aside with dd I was also charting everything so I knew exactly when I ovulated, which was closer to day 20. The first doctor I had kept calculating my due date from my lmp, but then by a fluke I saw a different doctor who actually listened to me about the ovulation date and said "oh well that makes sense why she (dd) measured a little small" (something that was never mentioned by the previous dr) Needless to say I switched to the new doc who would actually listen...sorry for the unrelated rant!

 

Generally they will go with the date the u/s says.

 

The thing I've always had with scans (even with my 2 singleton pregnancies) is that a scan could be showing that a baby is measuring 7 days ahead, but what if you're someone who has big babies. Couldn't that baby just be on the big side?

I hope that makes sense.

Also-and this may seem a silly question-if the babies are measuring differently and they take your due date from a scan, how do they decide which baby to date you by? The biggest baby?

 

My OB used the smaller baby.