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Really your situation is a bit unusual. It is unusual for the dr. to change your due date this late in the pregnancy. Unless you KNOW when you got pregnant there is no way to know the real due date. Im sure you are wanting to be counting down the days and planning your life, and it is hard with a 2 wk discrepancy. If I were to guess, I would say the baby will come sometime in the middle of those 2dates.. October 6 or 7th. Good luck! I am excited for you!

Just because the ultrasound shows an earlier estimated date of delivery doesn't mean your doctor will expect that baby any earlier.

Ultrasound techs measure a few key parts of your baby--like the femur--and apply a mathematical formula to estimate the baby's age from that measurement. The estimate is ONLY an estimate, and it's most accurate, I was told, around 20 weeks.

I also hear about all these people being told that they're having big babies, based on ultrasound. But ultrasound estimates of weight can be wrong by more than a pound, and babies grow at different rates.

The thing that bothers me about all this is that the combination of "big baby" plus wrong dates can mean that your baby might be born prematurely. If your doctor induces or performs a C-section because the baby is "full-term" and "big," but the ultrasound EDD doesn't match your date of conception, you may be delivering your baby early. And even though babies are considered full-term at 37 weeks, a recent study shows that babies born at 38 weeks have more health problems and FAR higher health care costs over their lifetimes than babies born at 40 weeks.

And 1 in 8 babies is now born prematurely, possibly because women are being induced early.

So stick with your dates, if you're confident of them. You know when you conceived far better than any mathematical formula!

hey, yes this has happened to me.. I was due Oct 1st last year and with my first ultrasound they told me i was due 21st of september instead because he was bigger, so they thought i mustve had dates wrong. I knew my exact dates though and it didnt make sense to me! but i just went with it. Towards the end at about where you are now, 36wks, i had another ultrasound because of his size, and they told me that his head measured up to be the size of a 40wk full term baby. So that freaked me out! So yes is the answer to your question, if they see a bigger baby when they measure they can change your dates. Just to let you know, you really could have your baby around the 1st. My baby ended up coming on the 21st which was the day that they moved it to. When the baby is big and theres no more room for them anymore and the only thing to do is come out early, so make sure youve got everything ready! Also -i knew my baby wasnt due on the 21st when i had him.. he came out with vernix allover him which is a sign of an early baby and also had jaundice which is another sign of an early baby. He was 9Ib 7. a pretty big boy! Vaginal birth.

Goodluck with your birth and enjoy you new baby. Congratulations

9 out of 10 times ultra sounds are not incorrect. However the doctor many times will take percautions and sometimes change a due date if the baby seems to be larger than what is percieved to be normal incase the baby needs to be delivered at a different time than originally specified.

my 1st daughter - i had a u/s and they said she was 16 weeks while in reality she was only 8 weeks... sooo of course they changed my due date and i ended up haveing her on the original date set which was 2 weeks post date from the new one they gave me. I dont know why they do it... and frankly dont think they know really why they do it. I would go by ur own personal instinct. Not to mention its easier to expect a far off date and deliver sooner than expect to deliver soon and end up waiting. good luck

Yes it happend to mean, they told me i was like 16wks or so according to lmp and i they said i was 18wks according to my u/s. The doctor told me that is just how big the baby is measuring. Or rather what they think the babies size should be at that at that month. Its like the corresponding size to the corresponding wk.. lol thats what they kind of explained it as. Sorry if that doesnt make sense, i hope that helped a little.

The most accurate measurement for an ultrasound is your earliest ultrasound. Most times OB-GYN's go by these measurements to determine the due date. As your baby gets bigger, it is less accurate due to the fact that everyone is different and grows at different rates. The measurements used for dating are femur length, head circumference, and abdomen circumference. Someone may have a skinny baby, or one with longer legs. It's just how they grow. It's very common for your dates to change due to the ultrasound measurements, but like I said earlier, the most accurate measurements are the earliest ones. Good luck!

This happened to me too. I never asked about it though. I just figured the baby was measuring bigger than what would be expected for my due date.

...she was still 3 days late...and I was induced because they were worried that she would get too big. She was nearly 10lbs...I'd say that was big enough!! lol

Even though your due date goes by your LMP, it doesn't mean that your baby is going to grow exactly at that rate. Some are bigger and some are smaller. So I wouldn't worry about it too much.

Hope that puts your mind at ease some! Congrats and Good Luck!!

Ultrasound image of baby is done and technician measures the baby's head based on that the doctor's project the due date. All doctor's I have heard say plus or minus two weeks anyway. As you stated also the baby will come when the baby is ready.

My stepdaughter is going thorugh the same thing- her 1st date was Oct 25 now- November 11

I tell you the same thing I told her...Count 10days from your 1st day of your LM then add 40wks....You'll get a better due date... maybe a day before or after depending if you ovulated between the 10th-14th day.. Its basically the same as the lil chart your original doctor said..

When she did it her due date is OCt 31st.

It worked for me and my 3

remember like you said all babies develop differently in the womb..so the ultrasound can get confused if the baby is bigger..

yes it happened to me the ultrasound not only goes by the size of the baby but also the development of the baby as well. I was one day early going by the ultrasound dates but I would have been a few days late going by my last period date. I also had a good size baby 9 Lbs 14 oz