Why does my baby favour one hand?

She grabs with both, but there's a favourite

That was the observation, and the question underneath it — asked outright — was whether it could be scoliosis.

It's worth taking that question seriously rather than dismissing it, because the reasoning is sound: a consistently stronger side does sometimes mean something. It's just that at this age it usually doesn't.

What's ordinary

Babies use both hands and swap which one they favour, often from week to week and depending on what they're doing.

True handedness generally settles much later than people expect — often well into the second or third year.

So a baby who reaches more often with one hand, or seems more confident with it, is ordinary. She's also more likely to use whichever hand is nearer to the thing she wants, which makes a preference look stronger than it is depending on where you sit.

The distinction that matters

Not which hand she chooses. Whether she can use the other one.

A baby with a mild preference still uses both — bringing both to the midline, transferring objects between them, bearing weight on both arms in tummy time.

A strong, consistent preference before eighteen months, or an arm she genuinely doesn't use, is different and worth raising. Early assessment is much more useful than waiting to see.

So the test we used: offer something at her midline, where neither hand is closer, and see what happens. And watch whether the less-favoured hand does anything at all.

There was a second one tucked in alongside it: when we hold her in one position she cries, and stops the moment we change it — is she in pain? She wasn’t. She simply had a preference. After all she is a little human being that has wants and likes too.

That's worth asking about directly, particularly alongside a one-sided preference, because a position that reliably causes distress can point at neck or hip discomfort rather than preference.

It isn't an emergency. It is something to mention rather than work around.