whats up with the delivery date?

[2for2]

Heres my issue my wifes lmp first day was on 12/29/09 we had sex on 13-18 of january, she didnt have a period in jan and she tested on th 28th and came out negative she didnt have a period in feb and she tested on the 23 and it was possitive. if i go by that information her due date is supposed to be 10/5/10 but the doctor has her being due at 40 weeks full term on 10-26 thats a 3 week difference. i kno that normally u/s are pretty acurate in first trimester, but  what im not confident in is that normally a pregnancy test will detect the fetus at 6-8 weeks. if thats the case that means wife got pregnant in jan 16-18 and 4-6 weeks later the test came possitive. If she had gotten pregnant until feb 8 which is what the dr is saying then there is no way that the test would have read + 3 weeks later. according to what i think this is her second c section so dr told us she can take baby out at 38 weeks. that would be in two weeks from today. but dr says it wont be till oct 12, can someone shed some light.. plz help.

[Elaine Brown, MD]

Hi!
I'm not totally sure that I'm following all you are saying, but here is what I come up with:
If your wife's due date is 10/26, that would put the date of the missed period at 2/15.  Most pregnancy tests are positive around the time of the missed period, so I don't see any problem with a positive test on 2/23.  From what I can see, everything checks out perfectly.  ESPECIALLY since she had the negative test on 1/28--we know she couldn't have gotten pregnant any earlier--only later.  If the ultrasound agrees too, I think your doctor is right on the money.  One thing you definitely DO NOT want to do is deliver the baby too soon.  Even 38 weeks is pushing it with a Csection.

Hope all goes well!
Dr B

[Tiffanymarie55]

Hi,
if your wife had an early ultrasound it is pretty close to being right on.  About the pregnancy test, a womans lmp does not guarantee that she ovulated exactly two weeks after that.  When I got pregnant my lmp was may 1st and I only got a positive pregnancy test July 15th.  Two and a half months later.  A pregnancy test can measure very very low amounts of HCG hormone which can apper as soon as one week after you concieve.  However in the medical world they tell you how far along you are by your lmp because not all women ovulate at the same time each month.  If your wides pregnancy test came up on the 23rd I would count back aboout three weeks to guess what would have been her lmp.  Which it sounds like that's just what the Dr. Told you.  If I was in your situation I would have confidence in the due date your dr gave you especially if you had an early ultrasound.  Good luck, and congratulations on your new baby