Fundal height measurements seem like nonsense to me...any doctors or midwives around to explain them...?

[frillingmeloftily]

Had a 26 week midwife appt today, and she checked my fundal height and plotted it on a centile chart.

It seems the weirdest, most open to misreading, dependent-on-body shape outcome to be measuring...is it really an accurate and evidence based indicator of risk?

They are customised centiles which are based on your height, weight, ethnicity and whether you've had children before.
The measurement is to measure the size of the uterus and it's contents, it has no reflection upon fetal weight.
The hope is that wherever you have plotted today you will continue to follow your curve of plotted measurements. If your midwife finds at future appointments that you have slow, static or excessive growth she/he should refer you for a growth scan, whereby the sonographer will plot the estimated fetal weight on your centiles.
Your next fundal height measurement should then continue on from the previous measurement, irregardless of where the scan estimated weight was plotted.

Hope this helps xx

That's really helpful! Thank you for replying.

As far as I can see, my notes have only one chart to plot these on - how is this normed for height / weight / ethnicity?

And the size of the chart means that the cross my midwife wrote today could be interpreted as anything from 50th-80th centile, I'd say. Does this allow for an accurate comparison?

My midwife told me that the chart is used just to see if baby is at any one point very big or very small - she mentioned growth scans if baby was ever below the 10th c and a repeat GTT if baby was above the 95th c. - that sounds a bit different from the charting over time...?

Sorry, that should say 60th - 80th centile.

It’s not that accurate but it’s impossible to keep scanning everyone all the time so it’s the best guide they have as to how your uterus is growing. If there’s any concern they send you for a growth scan to assrss you more accurately.

It depends on the charts used by your hospital- if they use the personalised growth chart from the perinatal institute then it is generated by inputting your height, weight and ethnicity. So there would only be one chart but it is unique to you.

The actual measurement is less important than the trend providing it is within the 10th and 95th centiles - next time you are measured your measurement should follow the same curve as the chart, if it doesnt then extra investigations should happen.

It's a form of screening and the idea is to puck up on any possible issues and refer for a more accurate scan.

Research shows without accurate training experienced doctors and midwives will have up to 7cm difference measuring the same woman.

Gap and grow has recently been brought in to retrain staff and try and standardise measurement. A long with customised growth charts.

Referrals should also be made for a change in growth pattern, not just top or bottom of chart. Growth should be accurately measured using a set square, it should never be between 50 and 80 percent.

I mean one cross shouldn't be plotted so it can be interpreted as being anywhere from 50 to 80.

I googled this a few days ago and found a research paper from 1970 saying it wasn't accurate! In summary, depends on the height and proportions of the woman as well as how strong her abdominal muscles are - all rather obvious!

www.researchgate.net/publication/51272224_Fallacy_of_the_Fundal_Height

In my case, it was a static fundal height measurement that prompted midwife to refer for growth scan that led to them finally diagnosing me with pre eclampsia. So they do work sometimes! You’re right though, it’s not a perfect science, but the only thing more accurate would be everyone having growth scans and that’s just not practical in our NHS.

That study was about measuring gestational age and not growth though. If done correctly, preferably by the same midwife each time on a customised chart then it is a useful tool to pick up growth abnormalities. Fundal height measurements wont tell you how big the baby is but will tell you if it is growing properly.

But it's a screening tool that is cheap and fairly accurate when used by the same (properly) trainer midwife each appointment. The individualised grow charts have been proven to reduce stillbirth rates (apologies I'm on my phone so no studies to back up my point) and identify excessive or static growth. It means that often women have an extra scan they don't 'need' but also that babies who are at risk should be picked up quickly before the worst happens.

@W0lverine that's a fair point! Interestingly though, you do still see various information on sites like this where the height equating to gestational age rule is still trotted out.

@Weathergirl1 it's not that long ago that we were still working with 32cm = 32 weeks etc. Not every trust uses the customised charts either which makes it even less reliable (although I think more and more trusts have them now). The key is having the same midwife at each measurement - the intra observer variation in measurements is a big problem

They are not very accurate but they can help determine if you might need a growth scan if the bump is coming up particularly small. Growth scans are not that accurate either....but they can pick up issues such as slow/no growth over 2 different scans, and this along with other indicators can help determine if induction or some other intervention is necessary.

Hmm, ok so if the charts are customised, I can sort of get it. And the idea of tracking over time makes sense.

But here we see a different midwife at every appointment, and it seems intuitive to me that there's going to be differences in their techniques and measurements. Also, I guess my trust is one that uses generic charts.

I'm 5'10 with an overweight BMI and a bit of a tummy even when I'm not pregnant. I'm very unlikely to drop below a 10th centile line on an un-customised chart, right? And my 5'4, size 6 friend would be unlikely to ever hit the 95th...even if her baby was massive....?

I agree OP, that they seem so old-fashioned as to be positively medieval. In my mind they hark back to the days when physicians used to ‘test’ urine by smelling and tasting it.

In my case it was wildly inaccurate. I measured fine for dates all along. Luckily, I was paying for private scans, as a scan at 34 weeks picked up IUGR, and my DD had to be born early at 37.5. Examination of the placenta after birth showed it was too small, and prematurely aged. None of this was picked up by fundal height measurement, of course, and had I been left till 40 weeks, DD could have died. I think it’s outrageous that the NHS doesn’t offer at least one extra scan in the third trimester as standard.

Done properly they make a massive difference.

When West mids implemented the gap and grow method the stillbirth rate dropped dramatically, can't remember off the top of my head the figures but rate was more than halved I think.

I'm on my third baby and have never had it plotted on a chart, let alone a customised one. How weird. My notes had charts in them I think, but nothing was customised and they were never completed. This time I've got no notes and an app instead (it's shit) and that has no charts.

It must vary by area...