How accurate are baby growth scans?

Birthing expert Jackie Heffer-Cooke asked mums who had to have an extra growth scan during pregnancy, if the scan results proved to be accurate when baby was born, here are the results.

The ‘Baby too big, Baby too small’ growth scan survey results

As you can imagine I see a lot of pregnant women. Around 80 of you lovely lot a week. As you know at the beginning of class we always go around the room and ask how you are, and over the last 18 months the amount of women who have commented of having extra scans for baby being suspected too big, or too small, has gone “off the scale”.

Baby Growth Scans

When your midwife tells you initially she wants to send you for an extra scan because of the size of your baby it is bound to be worrying.  Of course, midwives have different ways of expressing information, we hope that most of them do it in such a way to ‘normalise it’, rather than send you home in a state of fear or panic, but it is bound to make you concerned. Most women do not know that this is becoming quite ‘standard place’ and lots of women think that this is only happening ‘to them’.

If you are asked to go for an extra scan, it is not in itself too much of a problem, at least you get to check in and see your baby, which is kind of nice.  The troubles come when women are being induced early because of the results. And sometimes the results can be wrong.

Now, let me make it clear that what the hospital is doing is quite rightly minimising risk – this is the point and the incentive – and it is of course the correct one. Everybody wants a healthy mum and a healthy baby. However, I was curious as to how many babies when they are born are actually too big or too small –  so we put together a very simple survey and sent it to our lovely YogaBubs mums and the results are really quite surprising.

Our Baby Growth Scan Results

Our research was into the accuracy of baby growth scans. We had 34 women contact us who had extra growth scans. We asked ‘Were you told your baby was too big, or too small for gestation’ and 37% were told their baby was too big, and 63% too small. We asked, ‘Was this accurate when the baby was born?’ 16% answered Yes, 45% answered No and the rest were not sure what was normal or had other more complexed answers.

Baby Size ScansSo looking at the raw facts – we have 45% of women for whom the baby growth scans ended up to be wrong.

Now this is a very raw way of gathering data, and indeed I do not profess to be a psychologist or a data analytics specialist. Indeed, here we find that 15% of women could possibly have been at risk if their babies size hadn’t have been noticed, and that is important. Those women, those babies are so important.

However, the 45% of women who did have inaccurate scans may well have gone through inductions, which usually, not always, but usually lead to longer more challenging births that possibly needed some further intervention, when they didn’t actually need to.

What to do?

Now I am not a risk taker when it comes to healthy lives. But, I think there are questions from these results, and I think a discussion is needed within the NHS and real ‘proper’ scientific observations need to be done, not just quantitatively, but from a qualitative prospective too.

Every woman is, and should be, important when it comes to birthing, and perhaps, just perhaps, there are ways of avoiding these many women getting wrong advice.  Or, to look at it another way, if we are going to be giving many more inductions in this risk minimalising culture of birth, then what are we doing to support these women better when they are undertaking inductions? I think that’s ‘a can of worms’, but one that definitely needs to be really truly properly honestly opened and thoroughly looked at. It’s a fact that post-natal depression and trauma can come from difficult birthing so we must do all we can to make sure each woman gets the best birth possible – regardless of how she must birth her baby.

Get in touch

As always, your thoughts, and real life stories are appreciated. There is only one way to change systems, and that is to get a voice heard.  As a Better Birth Campaigner I am always willing to listen and report these messages back to the hospital via the MSLC – the Midwifery Services Liaison Committee – which is a meeting where I can explain to midwives and obstetricians what my service users really think – that’s you!

So, thank you for your input, to all of you who filled in the scan survey. If you would like to contact me after reading this, please feel free.

You have choice

To those of you who are pregnant reading this, remember you ALWAYS have choices and these should ALWAYS be explained to you in a kind, mature, respectful, and balanced way by whichever birth professional you are talking to, whether it is a sonographer, a consultant, or a midwife, and you can ALWAYS ask to see someone else if you are unhappy.

My aim in life is to help you birth without fear, and to enjoy your birth experience, whatever your birthing turn takes. So hopefully when you see articles like this it helps you feel like there are people rooting for you, and you are not alone.

Thanks for reading, and any questions you know where I am… just email [email protected] or visit our contact page.


*If you have been affected by your birth remember you can ask to go to Birth Reflections –  ran by the local NHS – to talk your birth through. You can of course also talk to MIND if you feel you need some help. If you feel you would like to take any matter further the MSLC will be pleased to support you if needed.