have you heard of this happening?

[k&Hmum]

have you heard of this and if so what was the outcome. My sis did a preggy test a couple days after her period was late and it came up positive so based on that and when her last period was the doc calculated her due date.

anyway all has been going well and the doc says the baby is in the right spot for age etc so today she went for her 19 week ultra sound and the person doing it said your not 19 weeks your only 14 weeks.

my question is how can that be because that means she is 5 weeks behind what she thought and would only have been about a week preg when she done her test and surely it wouldnt have showed up?

im confused.

[the_queen]

If her hcg levels were high enough, it would have produced the positive preg test. Maybe she ovulated late in her cycle?

[raffee]

It is possible, especially if your sis doesnt have a regular cycle (ie her periods arent every 28 days). Also, keep in mind that the U/S is not completely accurate, but there is up to 10 days either way (so she might actually be 15 weeks or so)...

[MZmama]

I am a late ovulater, my period used to only come every 3 months or so...

I did a test 1 week after my expected period, and it was negative, 4 weeks later i did another and it was positive. They sent me for a scan to determine correct dates and strangely enough i ovulated a week after i would've on a normal 28 day cycle.. so maybe she ovulated rather late...

Although they determined at my first scan when the doctor calculated i would be 8 weeks 1 day if i ovulated on time that i was actually 7 weeks 2 days, then at my supposedly 11 weeks 5 day scan they changed so that i was actually 12 weeks 2 days... the scan is more accurate then working out your dates etc.

[Lollie]

I think it might be wise for your sister to ask for a second opinion, and get another scan happening. Or maybe do a internet search on the subject so that you can gain a little insight on the topic and find some concrete answers :)

[JenNT]

ok if she originally did the test at 4weeks then technically she conceived 2 weeks prior so therefore there was no HCG 4 weeks prior iykwim....so her dates say 19....17 since conception...but 14? She shouldn't have had a +HCG when she did the test then as if they are saying she is only 14 weeks(12 since conception) there would not have been a baby for at least another month.

[Lollie]

Took the words right out of my mouth jenNT. I was trying to explain it but it got all muddled up so I thought never mind and just posted the above to help my brain from collapsing from thinking too much :laughing:
You are 100% right and you said it so nicely too!! :)

[kadownie]

The later on in pregnancy you are, the harder and less accurate it is to predict the gestation- being that different babies grow at different rates etc. If it was me, I would stick to the original dates.

If she is certain of when her last period was, then I would encourage her to trust those dates. If you go back to 14 weeks and she's 18 weeks- that's 4 weeks difference.

Defianately get a second opinion if she's worried- go to a specialist- there is such difference in skills.