Gestational age small in IVF pregnancy, has it changed my due date/ how many weeks pregnant changed?

[Dmw1984]

I had my 12 week scan last week and baby measured 11w6days. It is an IVF pregnancy and I should have been 12w3days. The sonographer said it was fine in terms of health. I also know from a harmony test I am having a girl and that they can measure a little smaller. My main question is now how do I calculate how many weeks pregnant I am, go by the gestational age or the IVF transfer date?

[Peony85]

Mine have gone with the IVF dates as these are known. Even though mine has measured days ahead each time, they’ve kept the original dates. Xx

[Ivfgotadream]

Really depends on your type of IVF or transfer? Mine was natural Modified IVF so no down reg so could date from my LMP but if you did long protocol then you need to go from IVF date. If you google IVF due date calculator there are a few sites which will tell you the expected gestation but at the 12 week scan they tend to reset the due date based on what you measure at that scan

[Dmw1984 in reply to Ivfgotadream]

Thank you, it was a frozen embryo transfer so according to the date of the transfer I should have been 12 weeks 3 days using those calculations. I was confused because the sonographer said they would use my IVF dates but when I saw my EDD on the paper afterwards they had moved it back 5 days.

[Ivfgotadream in reply to Dmw1984]

I don’t think the computer systems always allow them to be overridden?At my 12 week scan even though one twin was measuring a few days behind the other twin was measuring 5 days ahead they adjusted my EDD based on his measurements and just said that’s the policy/what the computer system says to do? But it means at every scan my little twin measures significantly behind her brother and she looks like she’s struggling even though she’s not!

[Cinderella5]

My NHS clinic moved my EDD backwards too.....I had a 7wk scan and was measuring a couple of days behind our IVF date. However when I had my 12wk scan I was measuring 3 days ahead of the IVF date and they didn't change it and left it as the early date so Im around 5 days out. I questioned it a couple of times but they just said it didn't matter and not to worry about it. Couldn't get anyone to commit to what the correct date was which I found annoying!!xx

[Hidden]

Not ivf but from my lmp I should be 16+1 but I’m 17w today, but at 12w scan I should have be 12+2 but put me as 13+1. I’ve just had a scan at 16w+5 she said baby measuring a little bit smaller but still within normal. So am I really 6 days ahead or not really? I don’t think it matters as long as baby is growing within the average measurements.

[Ketkoot]

Hi. I think every clinic does something different. At both my 8 and 12 week scans I was measuring ahead by 3-4 days. My fertility clinic didn’t change my EDD but the local hospital has. I don’t really think a few days either way makes a big difference!

Congratulations on ur little girl, we also had a harmony test and are having a little girl too. X

[Dmw1984]

Thanks for your replies ladies, yes I think it does depend on the clinic and as long as long as everything looks ok in regards to baby's health it doesn’t matter much other than me just wanting to finally get to the second trimester a little sooner! 😆

[KiboXX]

I think it really depends on your local hospital/CCG as they all have different ways of doing things. I measured 5 days ahead consistently through my scans but they never adjusted my due date as it was an IVF pregnancy, they explained there is no questioning the conception date as they know exactly when it happened 😂 My friend who lives in a neighbouring area but falls under a different care group had her due date changed based on measurements even though she was also IVF.

Don’t worry too much about it, especially if it’s only a few days xx