Any antenatal sonographers about? (Image included)

[ConcernedFTM]

Had my 20 week scan yesterday and the sonographer said that everything was perfectly normal.

Noticed when we got home that everything was plotted according to its percentile except for the CBT measurement. From what I can gather from google, this is the cerebellum measurement, something to do with the brain. I've also found information suggesting that this should be in line with the gestational age.

I was exactly 20 weeks yet the CBT measurement is 18.7. Does this mean anything? Why isn't it plotted on the paperwork and if this does suggest a problem, why didn't the sonographer comment on it?

Many thanks in advance - I'm hoping I'm just being a crazy first time mum.

It's in mm millimeters so I think it's nothing to do with how many weeks you are but simply a measurement that's been taken?

Maybe trust the expert that nothing is wrong or they would have told you otherwise. Otherwise ring up and ask them to explain it to you

Documents I've found (by googling) have suggested that this measurement should be in line with gestational age.

I've also found anecdotal evidence of women being offered abortions if the measurement is far too small because this leads to severely impaired learning ability/ motor skills. I just don't know if it being a little bit smaller than expected means anything unpleasant.

Should have called my midwife today I suppose but was busy at work all day and couldn't really cut away.

Also don't understand why it wasn't plotted like the other measurements were.

@SlB09 is it possibly to ring the sonography department at the hospital then? Any idea how I'd go about doing that because I can't find an obvious telephone number on the hospital website?

Do you have health anxiety OP?

Haha not usually, no!

Just first time pregnancy and obviously being a bit over the top but in lieu of badgering the NHS, thought I'd turn to a supportive collection of ladies who may have been through this before.

Thanks for asking after my mental health though - a reasonable question.

Yeah you can ring the hospitals main number/switchboard and ask to be put through. Quite complicated but this article explains that the cerebellum (CRB) measurement is unreliable and difficult to measure accurately increasingly so through the pregnancy and this is why it isnt used as part of the normal growth charting. Hope it helps, I really wouldnt worry yourself. onlinelibrary.wiley.com/doi/10.1002/uog.5225/full

If they have told you everything is ok I'd believe them and not google.

@SlB09 this is exactly what I needed.

'TCD measurement is not yet commonly established and is difficult to obtain, especially in later pregnancy; this makes it less reliable when evaluated retrospectively. Furthermore, different ultrasound planes and techniques may explain differences in TCD curves.'

Thanks for the info. Don't feel the need to speak to anyone now: just wanted to be informed. Thanks

I've had horrendous health anxiety in the past, that's why I wondered. Glad you don't have that.

I can't answer your above question, although I'm sure they wouldn't mind you calling?

Stop Googling! Ask your midwife or other hcp if concerned, googling will just give you opposite info and everything in between, about a subject you're not an expert in which means it can all be open to interpretation and confusion.

Are you completely sure of the dates? Were you moved forward at the 12 week scan? I had this (smaller TCD measurement) in my second pregnancy but took heart from the fact that the measurement seems unrelated to fetal size/ growth and is probably a truer estimate of gestational age than the BPD/ head circumference. E.g. www.ncbi.nlm.nih.gov/m/pubmed/10776012/

In my case I knew I was only 18 + 6 at my 20 + 0 week scan (because had had a scan confirming ovulation) so it was more that the other measurements were large for dates than the the cerebellum was small. By 36 weeks (their dates) the head measurements were both over the 99.6th percentile and when he was born (by c-section) his head circumference and weight were both large (39cm, 4.4kg).

Is it possible that you also have a large, young fetus? The 12 week scan after all only assigns you a date depending on the length/size of the fetus. It used to be thought that growth in the first trimester was completely unform across different embryos but this now seems to be being questioned. From my own experience of two pregnancies I know that my embryos seem to grow faster than the curve, so I was dated 6+2 at 6+1 (my dates), 8+4 at 8+1, 11+0 at 10+1, and 13+1 at 12+0... (had a lot of scans for unrelated reason!)

Either way doubt v much that this is worth worrying about. Another sonographer might have got a different measurement anyway (such a small structure), and if they were worried they would have flagged it up.

Hi @hopsalong, thank you for your reply! Yes, I was moved along by a week at my 12 week scan.

I had a dating scan early on which put me at 6+5 but was then moved from 12 to 13 at the NT scan so you might be onto something there. Unfortunately, I've not a clue re. missed period dates.

It seems that at birth, a small cerebellum can be a sign that the child is going to have developmental issues: most commonly with fine motor skills, speech acquisition and coordination generally, which is what worried me so much initially but you're right, they're working in such small measurements that there has to be a margin of error. Baby was also head down, which made it difficult for her to see the head and face anyway.

I just don't understand why there is no cross to mark the percentile. It would suggest that either they don't plot this at all (but why is the box there?) or it is so small that it's off the chart, which does scare me.

Stop googling honestly it's the worst thing you can do for your own peace of mind. Call your midwife but if the sonograoher has plotted the graph she knows the measurements and has said they are fine please believe her it's her job. Enjoy your pregnancy!.

@Teachervoice you need to chill out. They would have told you if there where any issues with baby. Get off the internet and stop scaring yourself. I'm guessing you are a teacher from your name so you are used to having to do research etc. This time just let it go and trust in your professionals. Please, for your state of mind.

Teacher, I think that really does suggest that you are a week behind the official date. In countries where they offer an earlier scan (e.g. US) the eight week date is taken to be more accurate than the twelve week one. (If you had really been 7+5 and not 6+5 at your early scan the sonographer would have seen much much more -- growth so rapid at that stage).

I don't think you should worry at all, as others have said. The cerebellum measurement may be wrong anyway, by even if it isn't, it's completely normal for 19 weeks.

The only thing I would say is that you should prepare to be a week overdue!

@Deckthehallswithjammydodgers that's my issue: she hasn't plotted the percentile, as mentioned in my original post.

@MummyGofboys I do appreciate you taking the time to respond but you're right, I am a teacher and I'm used to being in an environment where being inquisitive is not seen as a bad thing. I'm also not naive enough to think that 1) medical professions don't overlook things and 2) what might be seen as 'okay' by the NHS: for instance, having a child with developmental delays who can't access life in line with their peers, might not be okay with me and might be something I'd like to be pre warned about.

I hope I'm not coming across like one of these people who I see on the boards everyday who need to check with strangers because they've just done a particularly violent sneeze, but as I'm unable to speak to a midwife because it's the weekend and wouldn't dream of clogging up any other overstretched NHS service, I am posting on here for anecdotal evidence from the vast number of other parents who may have been in the same situation.

Thanks @hopsalong, your responses really have been helpful. Do you think the other measurements just suggest that I might be slightly earlier with a bigger baby?

This makes sense to me. Slightly off topic, I've just moved my mat leave a week later so that's an even better decision now!

I am aware that it is scary to think about problems that can happen in pregnancy, however you have had a 12 week scan and now a 20 week scan to check for any abnormalities. You have been told that everything is normal so I don't understand why you are questioning it so much. You seem extremely anxious about the possibility of a disability but haven't questioned it with a health care provider. I would maybe call an expert in that field and not look for advice on the internet. They can put your mind at rest much more than anyone on here can.

Hi, sonographer here! Yes it's true that the cerebellum measures roughly in mm the number of weeks that you but "roughly" is the key word here, it does not have to be exact! As long as the measurement fits into the normal range for your gestation then that's fine. Tbh it's more the shape and appearance of it that is most important and the sonographer will have checked that.

Please don't worry, your babies HC (head circumference) and AC (abdominal circumference) fit perfectly with your dates which suggests to me your EDD is as accurate as it can be

As a side note, and please don't take offence here as it's not intended, but teachers do have a well known reputation particularly in obstetrics for questioning the knowledge and ability of medical professionals. You've decided your dates are wrong because, through a bit of googling, that makes more sense to you rather than going with what you have been told by the people involved in your antenatal care. You trust google over the years of training and experience of a sonographer....it is just a teeny bit irritating

Haha @BluePheasant do we?! Whoops!

To be fair, I hadn't had a chance to ask the sonographer because I didn't look at the scan document until I got home. Had I been able to ask her straight away, I'd have felt totally reassured and would definitely not have googled it to begin with!

I really appreciate your response. I managed to check this afternoon with someone else who recently had their scan at the same hospital and it appears that a cross is never plotted on that percentile graph, which begs the questions of why it's there in the first place!

yep am afraid you do! Like you said upthread perhaps it's the questioning nature that makes you good at teaching. My DH is a teacher and even he does it to me sometimes! It's not a dig, it's just a bit of an in joke

Well I'm glad you have been put at ease. Tbh I don't know why the measurement isn't plotted as on our reports we plot every measurement on a normal range line. But our reports are a different format to yours, perhaps at your hospital they only plot the measurements that can be used to date a pregnancy. Either way it looks like it all fits perfectly with your dates, growing away beautifully!

Thank you: I'm very grateful for that fact! I am going to take from this experience that checking the paperwork before leaving an appointment and having a 20 second conversation can save you hours down the google rabbit-hole.

On the plus side, I feel like I know an awful lot now about current research into childhood developmental issues

Thanks ever so much for taking the time to respond to my thread.

Hi ConcernedFTM, how did it turn out for you? I’m in a similar position but can’t find much info out there that’s not so scary!! Thanks