Advanced search

Pregnant? See how your baby develops, your body changes, and what you can expect during each week of your pregnancy with the Mumsnet Pregnancy Calendar.

How accurate are fundal height measurements?

(17 Posts)
MayimBialik Tue 09-Oct-12 15:57:13

I'm measuring 38cm at 36+2 which according to my chart means the baby is at 8lbs now!! Am being sent for a growth scan on Friday. Am panicking I'm going to have a giant baby. Midwife actually measured it at 39cm the first time and then had me back on the table to remeasure.

MayimBialik Tue 09-Oct-12 15:57:54

So in the space of 2 mins got two different measurements!

annarob Tue 09-Oct-12 16:08:54

I don't know, think they use these as guidelines but everyone differs slightly due to body type, position of the baby etc! As long as all seems healthy I wouldn't panic! :-)

whatsonyourplate Tue 09-Oct-12 16:31:33

I've twice (in the same pregnancy) been sent for growth scans because I was 'measuring too small' for my dates, and both times the scans have shown the baby was bob-on average size. So I don't have a lot of faith in them to be honest. They never even did them with either of my other two pregnancies.

annarob Tue 09-Oct-12 16:37:23

Was Told I was on small side and would have to be monitored, plus every single person likes to comment on how small I am which as much as you try to let go over your head does leave you paranoid!! But have decided to be logical about it midwife says baby feels like a good size. Must be those amazing stomach muscles of mine!?! ;-) lol

reikizen Tue 09-Oct-12 16:47:46

NICE recommends measuring fundal height in the latter stages of pregnancy but admits that the benefits are unclear. I personally have my reservations about it as a tool to diagnose large or small for dates babies and yes, it is perfectly possible to get two different measurements in the space of 2 minutes (and the fact that the midwife remeasured meant that she was being a safe practitioner not an incompetent one)! Hence my lack of faith in it's accuracy! However, scans are equally unreliable in predicting fetal size but doctors love them and see them as the final word on the subject. Anyone who tells you they know how big your baby will be is deluded. Until they are in your arms you can never be 100% sure how big they are or of the sex. It doesn't matter how large your baby is as long as they fit through the pelvis. I have known 3kg babies get stuck and 4.5kg babies sail out no trouble. If you are fat your measurement will be elevated also as the measurement will include your body fat as well as your uterus.
Have faith in your body to grow your baby and be aware that you do not have to go for growth scans if you don't want to (I wouldn't personally). smile

MayimBialik Tue 09-Oct-12 18:56:35

I'm not fat and have not put weight on anywhere else. I did have a full bladder when she measured me so maybe that could affect the results?

I will have the scan because I want to give birth in a midwife led unit and this will determine whether I'm able to or not

CaptainHetty Tue 09-Oct-12 19:01:58

They aren't, to put it simply. I measured above the 90th centile all the way through pregnancy, according to growth chart she was going to be 9lb+...

I had her 8 days ago, on her due date, and she was 7lb 7oz.

Even when they give growth scans they say (or at least they do at my local hospital) that they can be a pound out either way, so nothing is entirely accurate.

StrawberrytallCAKE Tue 09-Oct-12 19:10:09

I was told my baby was measuring on 95th percentile, my amniotic fluid on 95th percentile from a scan but my fundal measurement was on the 50th percentile so I don't think any of the methods are too reliable. Like above poster said as long as your baby is healthy try not to worry.

Lora1982 Tue 09-Oct-12 20:34:12

ive just been measured at 31wks today when im 27...! im having a scan tomorrow, im not worried to be honest, everyones different to whos to say babies should be. maybe im having a big fatty, maybe becaus i was a size 16 before this has added to the bump who knows.

i just like the idea that perhaps this time my pic will be a decent one!

sammyleh Wed 10-Oct-12 10:07:24

I'm 38 weeks and have measured 34 since week 34... I'm really not worried. I know baby's head is now engaged which drops your sizing down a fair bit so I'm told. Baby is moving fine, I feel fine and just want to meet the little monkey now! I've always thought measuring a stomach is an unreliable way to say how big a baby will be. No two women are the same size so it just doesn't make much sense to me.

whatsonyourplate Thu 11-Oct-12 13:27:07

Well I've just seen my midwife at 39+2 and I'm still measuring 34. So she's sending me for a third growth scan. I had one two weeks ago and they said baby was fine - it's not like she's going to have shrunk is it? I certainly don't feel as large as I did last pregnancy, but I've got an anterior placenta this time, so I'm wondering if that affects the size/ shape of my bump?

MayimBialik Thu 11-Oct-12 16:58:03

I have an anterior placenta too - except I'm measuring large. Hmmm - it does all seem quite inaccurate hmm

whatsonyourplate Thu 11-Oct-12 18:18:04

Ah, that scuppers that theory then!

Dinosaurdrip Thu 11-Oct-12 18:32:46

I am measuring 35 weeks at 29 weeks and have had a growth scan where everything was "normal" and she is spot on average size. I measured perfect with ds1 throughout my pregnancy and he turned up 2 days late at 10lbs so I dont think it's a very good indicator at all.

BedHog Thu 11-Oct-12 18:43:50

Fundal height measurements were developed as a way of estimating approximate gestation (and therefore due date) in third world countries where scans and pregnancy tests etc weren't available, and women often had pregnancy after pregnancy with no period in between so it couldn't be dated by LMP. They aren't particularly accurate, but are a useful tool for highlighting women measuring much bigger or smaller than average so they can be referred for further scans or testing if necessary.

cupcake78 Thu 11-Oct-12 19:05:38

Was sent for growth scans and told baby could be small. He was 9lb 5ozswink

Join the discussion

Registering is free, easy, and means you can join in the discussion, watch threads, get discounts, win prizes and lots more.

Register now »

Already registered? Log in with: