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Pregnancy

can my dates be wrong or is she just a big baby????

6 replies

charzie · 25/02/2010 12:59

by my dates im 30+4. by 12 week dating scan they put me a week behind. so by scan im now 29+4. 1 week behind. since my 20 week scan iv bin measuring ahead. how accurate are dating scans? also iv worked out the date of conception from the scan dates and quite sure that i had already concieved by then.can they be 5 days or so off? ne one else experiencing this? good luck with all ur pergnancies

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BooyhooNOTboohoooORbooyou · 25/02/2010 13:02

my scan dates had me conceiving a week after i know i had conceived and even at that ds wa born 6 days after my due date so i reckon the scan must have been pretty accurate. dont know how though. HTH

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FatSeal · 25/02/2010 14:38

I think the dating scans are pretty accurate up to 14 weeks or so, as I was told that the foetus grows and develops to an exact schedule up to then. After that individual variation starts to occur, so later scans probably have some room for being slightly off.

I was more than 2 weeks out on my dates, but my cycle was so trashed from mcs beforehand that I was perfectly happy to go with the scan evidence. Also it's pretty obvious the difference between 7.5 and 10 weeks!

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hippopo · 25/02/2010 17:51

I am 100% sure off my dates give or take one day. Have been tracking my period and ovulation dates for two years and I have always been 28 days like clock work.

The month the conceived we actually only had sex twice (one day after the other) so was pretty confident with my dates.

At 8 week scan (went private) they agreed with my dates. But at 12 week NHS scan they brought my due date forward a week. I have since changed hospitals and new MW has said lets stick with your dates as I trust them more!

Hope this has sort of helped and sorry for little but of ramble!

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mummyof2byapril · 25/02/2010 18:14

Early dating scans are accurate, by 20 weeks baby's size starts to be down to genetics and not actual age.

You are only actually pregnant for 38 weeks, pregnancy begins at implantation of fertilised egg.
Many birth controls can work by killing fertilised eggs before implantation but they aren't concidered as abortions because they discard zygote before implantation.

Implantation can occur as long as 10 days after the sex, and 7 days after new life is technically created.
Sperm can live for a 3 days, finds egg and connects to create zygote, zygote takes upto 7 days to implant in womb lining, suck up nutrients and start developing into an embryo.

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mummyof2byapril · 25/02/2010 18:20

www.babyhopes.com/articles/conception-implantation.html

According to this source:

"it is possible that it can be as many as 7 to 14 days between the time of sexual intercourse and the time that the fertilized egg implants in the uterus."

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xxkt1xx · 25/02/2010 18:29

i had my due date down as 22nd may...scan came back as 23rd so i think pretty accurate but i reckon 5 days difference is allowed xx

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