Can someone explain weight percentile to me please?

[Sparrowlegs248]

As i always understood it to mean (and have read on here) that if DS was on the 25th, out of 100 babies of the same age, 75 would be heavier?

In which case how was he on the 25th when he was 9lb 1 at birth? Confused!

[KaluzaKlein]

That's about the 75th percentile. 25th is about 7lb...

www.cdc.gov/growthcharts/data/set1/chart01.pdf

American charts , but the eu ones are sinilar

[Sparrowlegs248]

That's what i thought but it definitely says 25th for each weigh in until this week which was 50th at about 16lb 3 at 4 months. Hence my lack of understanding!

[GreenSand]

He wasn't on the 25th centile at 9lb+ at birth.
He might (unlikely, I'd have thought) been on the 25th centile by a 6 week check, but that would have raised eyebrows and triggered questions by a decent HCP.
Mine were about 7lb, 25th centile, and 8lb, 50th.
Are the numbers plotted on a graph? That can help you to see what's going on.

[GreenSand]

Are you in the UK?

[WorldsBiggestGrotbag]

Mine was 8lbs 8oz and on the 75th centile at birth. She was 12lbs 5oz at her 6 week check and up to the 91st.
Are you looking at the right line on the chart? They can be a bit confusing.

[Sparrowlegs248]

I Will have aother look but the even said 25th. And last week he had 'gone up to the 50th'

There was also a big fuss when he lost weight. T

I didn't think it made sense!

[Sparrowlegs248]

Yes I am in the UK.

I'm not normally this dense! He's very long,.do they take that into account (he looked skinny for ages)

[KaluzaKlein]

Yes they plot all three measurements separately.

How odd. Talk to whoever is putting the numbers on his chart. It sounds like they're using it upside down but surely that couldn't happen...? Could it...?

[tiktok]

Perhaps they have recorded the weight incorrectly or told you the weight incorrectly or translated metric incorrectly.

[squizita]

It's a data entry error so to speak. My DD was on the 25th at 6 lb 14oz at birth.
And a hurried HV had her leap to the 50th a few months before. I looked and they'd plotted the graph wrong, I rang up and checked, and they re-plotted it next visit. :)

[Sparrowlegs248]

I've checked the book. The birth weight wasn't plotted, the first one was after he had lost weight and although that time and the next three weighs the HV said he was tracking the 25th centile, its actually just under the 50line. Last week the HV said he had 'gone up to the 50th' its actually halfway between 50 & 75. So that makes more sense.

[lullaby23]

OP I like this website as am too dim to plot graphs (also not in UK so don't get the same book):

www.paediatrics.co.uk/nicu/growth-charts