Small fetal head circumference

[Hest]

Hi, I'm 37 weeks pregnant with my second child. My first child had a head circumference in the 20th percentile but weight and length in the 98th at birth and there were no problems, she's beautiful and very bright!... however, last week at a scan at 36 weeks gestation to see if my low lying placenta had moved it was noticed that whilst baby's femur length and abdominal circumference were ok in around the 20th percentile (altho slight drop in AC) her head circumference was now on the 3rd centile. Whilst this is in similar proportions to my first child, just smaller overall, i'm still very worried. It's such a low percentile reading for the head. I know that usually fetal growth restriction is usually a bigger problem when the AC is proportionally small compared to the HC, but I'm worried and my miidwife isn't very helpful. they just said it shoul;d be ok and if its not its too late. But if she'd not growing maybe it would be better to deliver her now. I had a doppler of the umbilical artery which was normal, but she only looked for a few seconds at it and didn't check anything else. Anyone else had scans like
this? Was your baby ok? Ever so worried so please let me know x Thankyou

I am certain that the ability to measure these things in vitro is inaccurate. I was told that often the predicted birth weight was more than 25% above or below the expected. I am sure thats the same with circumference. Can the midwives refer to you to anyone, if you want a 2nd opinion? Are you near the Fetal Medical Center in Harley St? They can do highly effective scans and that's all they do they are experts and can probably reassure. you.

Hi

Similar situation as you, except, small BPD and small HC was picked up at 20 weeks (3rd centile) with all else normal. I was told to come back after 3 weeks but was so worried that I had a scan done with Prof Nicolaides at the Fetal Medical Center the following week. Everything measured spot on when he did it. But when I went back for the NHS scan at 23 weeks, HC and BPD were still close to the 3rd centile. The consultant who did this scan had trained with Nicolaides. She told me I had nothing to worry about. My guess is that they are using different charts.

Nicolaides said that HC and BPD were the most difficult parts to measure accurately. Also, my baby was breech, which affects head shape, thus, measurements.

My consultant and my colleague at work (Down's Syndrome expert) reassured me - both said that if Nicolaides said all was ok, then I had nothing to worry about.

Also, they only start to worry about measurements if they drop of the chart.

Good luck with everything!

Thanks for your replies! I feel a little reassured that other people have had similar experiences - unfortunately there isn't anywhere close to go private and I'm not sure I can afford it at the mo! I'm in for another scan this monday, Last scan showed that blood flow to baby through umbilical artery was ok but that all over growth was dropping slightly with no explanation. they said if she's still not growing they can get her out slightly early - I'm booked for a section anyway on Dec 27th so not too concerned about that, I'd be over 38 weeks anyway so baby should be ok. I've been most worried there maybe some chromosomal abnormality or something - but my Downs risk after Nuchal Translucency and blood tests was put at 1 in 9,400 so hopefully its not that. I will love my daughter whether she has problems or not but obviously I hope she doesn't, Good to hear the HC is one of the most difficult parts to measure! my baby until recently was usually transverse - turned about week 36, so it may also be that, like a breech, she's a bit squished!thanks for your posts! Roll on MOnday and the next growth scan. I'll let you know how it goes, keep me updated on your too! H xxx

It was my friend not me, so I don't recall all of the details (3 years ago now) - but basically they had told her that the baby's head was too small, that it had one long leg and it would be very underweight - much much much worrying later she delivered a very healthy, perfectly formed (both legs equal in length, head perfectly in proportion) 9lb 10 bouncing baby boy - only to be told that 'it's not an exact science you know' They failed to mention at any stage through her pregnancy that they'd only measured one leg and yes it was long - all of him was long - including the other leg!!!

I woudn't be suprised if you didn't believe me though - if she wasn't one of my best friends and I hadn't been at half her appointments (and many nights of tears & worrying!!) I don't think I'd believe it either!!

Thankyou! its good to hear of someone with a great outcome! anyone else had something similar happen? were there problems with your baby or was everything ok? x

i had scans at 20, 29 and 31 weeks and all scans showed that the baby was small (around 20th percentile) but all within range. she was finally born at 8lb9oz - far bigger than all the scans predicted....

At my 20 week scan my baby's measurements were all under the 10th percentile, HC 5th, except femur length which was 40th percentile. I am 28 weeks pregnant now but still worried about these measurements. I was told that it was fine and was not invited back for further scans. I was told that they are only concerned by measurements that drop off the charts. This week I brought it up with my midwife and she equally said they are often inaccurate by 25 %. I totally appreciate why you are concerned though.

Goldenbear - read my post above. They had my friend in a right state & spoilt her pregnancy with constant worry - all to deliver a wonderful, healthy, bouncing baby boy.

Chipping it - thanks for sharing.

Goldenbear - my consultant said that normally they would not have asked me back for extra scans as they wouldn't be worried about HC being close to 5th centile, but I am a high risk case for other reasons so the extra scans.

I have to say that I am still anxious about it. I have my 27 week scan tomorrow.

sh77,
How are you getting on? at what stage are you at now? I guess around 31 weeks?
I wanted to add my comments and situation too, and see what happened for you?
This is my first post.
I am high risk too - 41 and lost a baby at 21weeks in 08 due to congenetal heart disease.
At my 20 wk scan (am 23+1 now), i was told my baby was 2 weeks behind. I have been refered to fetal medicine locally and have got an appt with Prof Nicolaides tomorrow. Thats how I came upon this thread by searching for him.
I am paranoid that I am not growing or gaining any weight. I worry about the slightest twinge. I have also been told I have low amniotic fluid and a reverse flow on ductus venous. Hoping to get some reassurance tomorrow that I will have a baby and not another loss.

Hope all's well,
hsmom

I had something similar with DD1.

Was told she wasn't growing as they would like.

Was told she was going to have "issues" - they had seen something on the scan (iirc to do with her stomach??)

She was going to weigh under 4lb

They had a team on standby in case she needed to be transferred to the nearest big hospital.

She was 7lb7oz perfectly fine and is currently playing the wii in the other room.

She has had a D&V bug for the last 2 days wonder if it's related??

hsmom really sorry for the loss of your baby and hoping all will progress well for you in this pregnancy. I am high due my daughter passing away unexpectedly shortly after her birth and 2 MCs after that. So, I do know how you are feeling - pregnancy after loss can seem like a very long and anxious journey. Anyway, thank you for asking about me. I am 31 weeks and will have my 32 week scan next week.

Mumsnet is really an amazing source of info and so it might be worth posting your own thread.

27 week scan showed BPD (head width) to have fallen below 5th centile. But OFD (head length) was normal and head circ was around 10th centile. The consultant who is doing my scans (works with Nicolaides) wasn't worried. My own consultant obst wasn't worried either as he said baby's head is rugby ball shaped rather than round. He said that as baby's tummy measurement is normal, growth is fine.

Re your measurements - were all measurements 2 weeks behind? As my baby's BPD was small, the overall weight was recorded as small. This is because a mathematical formula is calculated which takes into account various measurements. So If one measurement is off, overall weight/size will be recorded as small. These measurements have a 25% margin of error.

Other thing to take into account re baby's size is your shape and size and your partner's. The conventional growth charts do not take into account maternal BMI and ethnicity but when customised charts are used, baby's size tends to be more accurate. I am very slim and didn't start to show until about 24 weeks. I was worried also about not gaining enough weight. I have made more of an effort to eat more this time.

Re low amniotic fluid - my levels and baby's growth had fallen in the final month in 1st preg. Don't know if I was slowly leaking fluid or if placenta was starting to fail. Not sure what causes it in earlier stages of pregnancy but rest and increased fluid intake are important. Fluid levels are replenished by baby's urine as so docs may well check baby's kidneys in depth.

It is really good that Nicolaides is doing your scan. You may have a long wait and so take something to keep your mind occupied (though I struggled due to nerves).

Perhaps try to write down a list of questions to ask Nicolaides tomorrow, e.g., cause of low fluid, implication of reverse flow.

I will keep you updated. Please feel free to email me.

Really hope all goes well tomorrow.

xx

sh77
Thanks for your speed of reply and reassurance.
All measurements were on the low side, AC and TCD came in just above the 5th centile. everything else was below. They stated that estimated weight was below 10th centile.
The notes said that IUGR which is diagnosed before 24th week can indicate a secondary growth problem.
Will do the list of questions.... thanks again for the advice,
hsmom

I read this thread and just wanted to update for anyone else who may be going mad searching with google.
I had a growth scan at 36 weeks as I was only measuring 34 weeks.
HC was below the 1st centile-told no action wait and see.
I then had another scan at 41 weeks where the HC had increase to the 4th centile and weight was showing as 8LB.

The next day I had a little girl 6lb 6 with a HC 37th centile. I hope this helps someone not to worry as much as I did.

Not totally experienced with this as such but I was told my baby was going to be small. Had growth scan. Predicted ( based on measurements and their 'charts' ) he would be 6lb 8. He was 5lb 6. So they aren't accurate in my view. As long as they are keeping eye on you and baby.

My baby’s HC was 7%tile at 20 weeks scan got another scan next week to check going out of my mind with worry and google keeps suggesting microsephaly

How did you get on if you don’t mind me asking? I’m experiencing a similar situation. I went for my 20 week scan and they said baby’s head js measuring too small below 3rd centile, ask me to go back 4 weeks later, I’m 25 weeks now and when I had a my follow up scan they said her head circumference has grown now to the 6th Centile but it’s still below what they expect. At week 20 they mentioned microcephaly. I’m beyond worried, they want me to go for another scan in 2 weeks time to check her progress.

I am 28weeks now, I had a scan at 27weeks 5days and they said my baby is in breech position and BPD and HC are both

@HomefromHome1- I forgot to mention you in my previous post. Thanks for your message

Hi @aaaluri3395. How did your baby turned out? Is she doing great? My baby had 2 percentile head circumference and they opt me to go for amniocentesis and torch. Which ive done it and just waiting for results. I just cant stop thinking about it

I gave birth to beautiful baby girl last month and she’s perfectly fine. Its just that she has small head due to genes. I was so scared when they said it was less than 1st percentile, I even met a MFM. They scare us with this percentiles. Don’t worry your baby will be fine too..

@aaaluri3395 omg. 😍😍 thats a good news. Just had my scan today as well and baby’s head went up to 5th percentile.. im still hoping she’ll turn out to be normal..

She’ll definitely be..Good luck 😊

@aaaluri3395 thank you. ❤️

Also going through this just now. Thank you so much to everyone sharing their stories! I keep reading them over and over to remind myself these percentile and scans can be misleading. I know I'm not as pregnant as they think I am, I'm about 10 days behind, and my baby is squished up under my belly button for every scan so hard to get a good measurement. I think I might have gone mad worrying if I hadn't read these messages!