LMP and US Date difference.

[babyhopes2323]

Hello ladies,

this is another post about lmp and Ultrasound date difference.

Im supposed to be 20 weeks tomorrow according to my LMP. 17 JAN 2011.

I went for a scan today and instead of measuring 19 + 6, bubs was measuring 19 + 1 and the measurements were as follows:

BPD: 41.9mm (18wk 5 days)
H.circ: 163.7mm (19wk 1day)
Ab. Circ: 134mm (18wk 6 days)
FL: 30.9MM (19wk 4 days)
Tibia: 26.8mm (19wk 5 days)

Then they have stated my LMP due date as 24.oct 2011

and US EDD : 29th oct 2011

Now i know that sometimes due dates can be back and forth by 1 week or so, but im concerned about bubs measuring 19 + 1 as they have summarized it in one sentence

: single viable fetus of gestational age 19 weeks and 1 day. im supposed to be half way done tomorrow..

any advice or ideas ladies? i know that sometimes measurements can go wrong and theyre not always accurate, plus the baby was in a cephalic position ( head down ) position. i googled the cephalic position which is basically delivery position and there was a post on Bnb a while ago saying its normal cuz there is a lot of space for bubs to go somersaulting around now.. but any advice on the dates would be very much appreciated..

thanks a bunch !

 

[babyhopes2323]

i was wondering whether or not to post a thread and maybe i shouldnt have its quite disappointing when nobody wants to answer at all and there are other threads that get answered in an instant. i wont be posting a thread anymore if this is the response .

 

[prettymachine]

i know mine measures ahead every time, and every time i ask if this means she will be born early, and every time my dr says, unless its 2 weeks different(forward or backward) its still based on LMP because every baby grows different. my US EDD has never matched my LMP EDD. they say LMP is the MOST accurate because of the difference in the way babies grow. so i would stick to your original DD and ignore the ones on the US

 

[nicnicjayne]

I really don't think people are ignoring your thread but I just think it is one of those topics that people really can't answer without really specific medical knowledge.

I went to my 12 week ultrasound and was told my baby was actually 15 weeks. Now this doesn't tie in with my LMP dates at all! Best just to wait and see what happens need the end. As my old-school midwife told me 'baby will come when baby is ready!'
Very frustrating when you want to plan everything to the last detail though!

 

[ellie27]

There is only 6 days of a difference between your dates by last period and scan - thats good!! A lot of folk have quite a big difference.

Go with your scan date as that will be more accurate.

The reason why your date is out and the reason why most other womens dates dont match also is that we all do not have a perfect regular 28 day cycle ovulating on day 14.

Nothing to worry about at all!

 

[we can't wait]

Don't get so discouraged if your thread isn't answered immediately. Firstly, this is a very specific question, so if no one has a personal experience they can't really answer. Also, there are people from all over the world on here- loads of different time zones. For example, it's 2:13 in the morning in my zone, I just cant sleep. So don't be turned away from posting! Its just a bit quiet around this time.

If your doctor didn't mention anything about it, I don't think it's anything to be concerned about. When I had my anomaly scan at 20+1, the baby measured 19+5. My doctor said that it's completely normal, because the LMP doesn't say specifically when you ovulated anyways. Some women are much farther off in their scan dates. I really don't think it's anything you should be worried about though. I think it's fairly common. If you are concerned, ask your doctor about it.

 

[princess_bump]

i think if your doctor is happy with your dates and baby is obviously growing fine, a few days or a week or so either way is fine i'm no expert but i no there are a few factors that affect dating and us is much more accurate than lmp. for example. you could have ov later, baby could of implanted later etc.
i never had a lmp to go by this time due to previous loss, but i always ov later and i thought i knew when we conceived, but i was still a day out with my dates.
i also remember being put back with our daughter as again, i ov later and conceived around cd 28 of about 31!
i honestly wouldn't worry to much

 

[babyhopes2010]

dnt worry the most accuarte are early u/s after that they can be a week or so out x

 

[knitbit]

The further along you are, the less accurate the ultrasound dating is. At my last scan, one twin was measuring right on and the other was 5 days ahead. The tech said some babies grow in spurts, so you may catch them right before or after a growth spurt. I wouldn't worry, your due date is a +/- 2 week window anyway to account for all the variability. About the only thing you can be assured of is that your baby is unlikely to be born on 17 Jan, LOL. Only 5% of babies are actually born the day they are due.

 

[babyhopes2323]

Thank you so much ladies for all your responses !! wow i must be hormonal to have stated things like i did.

i guess i will stick to my LMP and will ask my doc tomorrow at my anatomy scan. its encouraging to know that others face the same with difference in dates and ofcourse you ladies are experienced so thanks a bunch !! i was worrying for no reason ! xxxxxxxxxxxxxxxxxxxxxx