Can scales just be wrong?

[KiwiPanda]

I took DD to be weighed this morning and apparently she's lost weight in the last few weeks. Only an ounce so no one was worried about it, but the reason I ask is that I SWEAR she feels heavier than she did a few weeks ago, she's eating lots (solids and BFing) and when I have weighed her on my scales at home (by the admittedly nonscientific method of standing wtih her on scales and subtracting my weight, but usually it works out pretty much same as HV weighings) she's gained weight...

So... can they just be wrong??

Yes they can be wrong. There are lots of guidelines about how to get an accurate weight on scales, eg standing on a flat surface and regularly calibrated.

There are all sorts of things that can affect the reading.

Was it the same set of scales as last time? Had she just had a wee/poo before weighing this time round, or had a wet nappy on last time? Was she fully dressed in similar clothes both times? Are you sure there was no mistake in converting from metric-imperial or vice versa?

Well, she definitely had a quite big poo this morning and was also due a feed.. but the difference between what I thought she would be (and I usually kind of know, IFYWIM) and what she was was 1/2 lb, which seems a lot!

Wasn't nappy or clothes though cos they weigh them naked at my HV place.

Oh the other thing is that I put DD on the scales then took her out, because I noticed that the scales had started reading on a minus number. I thought they were on 0 the second time but maybe this indicates that they weren't working properly/ not calibrated/ on a non flat surface??

Weighing is subject to so many potential errors:

• wrongly calibrated scales
• incorrect reading of the scales
• incorrect writing down what the scales say
• mistranslations from metric
• wobbly baby
• not weighing baby naked each time
• old scales

When it comes to comparing weights over time, two operators and two scales can differ a lot.
In addition, one weight on its own is never significant.

In fact, weight in general on its own should never be significant - babies who are healthy and feeding well don't need to be weighed, really, but because we like doing so, we do it! New guidance is no more often than monthly in the first 6 mths (after the first two weeks and/or after birthweight achieved) and no more often than every 2 mths between 6 mths and 12 mths. Anything more often is misleading.

Thanks Tiktok that's very reassuring. She is an incredibly wriggly baby (HV asked me today: does she ever keep still? Er.. when she's asleep??) so that can't help. To be honest I know I shouldn't worry because even if she HAS lost a tiny amount of weight it's so small as to be insignificant. She's happy, eating well, full of energy so is clearly fine.

Funny how we all equate weight with health when they are babies then spend most of our adult lives trying to shed it