How Accurate are Scan Measurements in Late Pregnancy?

[maretta]

I ask because I am 39 weeks pregnant.

A week ago at my ante-natal, I only measured 34 cms so I was sent up to the hospital. I was put on the monitor - no problems and then scanned. The baby measured in the normal range for my dates and some measurements were actually slightly above average. So again no problems, I just apperared small.

Anyway, yesterday I had another ante-natal and still only measure 34cms. My reaction was -so what - I've had a scan and all seems fine. What worried me a bit was the amount of flaffing that went on to decide whether I should go back to the hospital to be measured again. In the end the consultant got involved and didn't want to see me.

The only thing that worries me is why the midwives seemed so worried - surely if my scan measurements are fine, the baby's fine??

i have lots of growth scans during my pregnancies as i have diabetes & the baby needs to be closely monitored. i had a scan a week before i had dd & they estimated her weight to be 2.8kg. she was 3.01kg when she was born, so i reckon pretty spot on.

not very I would say! My DS was measured at 11.5lb and I almost fainted -- had a csection and he was 9lb12oz!! I was toldthey are 10% inaccurate either way

I have had late scans because the midwife was concerned my bump was small for dates, scans showed baby was fine size-wise. Are you tall? If so, it is very common for your bump to appear smaller - there is more room inside for the baby, IYSWIM

I am tallish - about 5'7". My ds was only 6lb15oz and he was ten days late so I'm not expecting a big baby either.

Instinct and logic tell me there's nothing to worry about but that's just made me very confused as to why the midwife seemed to be getting so anxious.

Having seen my consultant this morning, he said that after 36 weeks, it's common to measure less than the maximum 36 centimetres as once the baby's head engages, it automatically drops lower into the pelvis, therefore a lower reading. I'm sure it's nothing to worry about. HTH.

Depends whether you're bothered about length or weight I suppose? I was scanned in labour with dd because she was an 'interesting' face presentation and they told me she'd be about 8 1/2 lb - she was born 9lb 2 a couple of hours later!

lol Rachey1969. Face presentations are very "interesting" aren't they? My dd3 decided to make her appearance that way and with a hand by her face for good measure!

My scan measurement at 37 weeks was spot on - said about 2 kg and dd was 2.072 kg (hence an immediate induction followed by c-s).

Why the immedidate induction Hazellnut? [puzzled]

I was told to take back all my newborn clothes as I would have a biggy!!!!
He was 10lb 2oz

Well, ours was very inaccurate, and this was with fancy equipment privately with an extremely experienced consultant sonographer.

Our baby was delivered 4 weeks early with IUGR as dw had high bp and the placenta was not operating effectively. With hindsight, the lack of weight gain and slow down in height of fundus were signs that something was not right and this should have been investigated.

Maybe they are just being particularly thorough, but IUGR, from our experience, was hard to catch through scan / measurement...

hth

Robina - dd had been monitored for growing slowly and had not grown for 2 weeks by this stage... Also I had high blood pressure at this point so both these together meant dd had to come out quickly. Sorry hadn't made that clear !

IME the IUGR was spotted through scans but maybe I was just fortunate. However, my bump was always the right size by tape measure so IUGR wouldn't have been spotted if it hadn't started so early (at my 22 week scan).