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Baby/ 7 month old stiffens legs/arms usually grunts.

2 replies

MAMAJT0 · 25/09/2025 07:17

I wanted to ask whether anyone’s baby is doing the same. Mine is 7 months and around aged 4 months he started to do these tensing movements. At this age his arms will fling out and be straight and sometimes by his side, his legs would straighten, chin buried in his chest and would make like a grunting sound. Eyes would be open, he would look at me so I could get his attention, mouth closed. It would last maybe a second or 2 and he would stop. If I called his name or got his attention he would stop at times. It mainly occurred when he was in his seated rocking chair at the time, maybe sometimes when laying down on his back. I flagged it to the doctor then. As some time went on we noticed it reduce or just not noticing it as much as before. Then when he turned around 6.5 months it happened again and now he does it in a range of situations, so laying down, maybe when sitting up playing, or just sitting there, especially in high chair when we would be feeding him. The same movements a grunting sound, recently a little without. Legs straight and arms maybe not as straight but they appear tensed. A few seconds. Sometimes in clusters. it can occur a few times in the day hence my concern, I definitely noticed in the morning, midday and afternoon. He has seen a Dr who ruled out seizures and reckoned it could be behavioural but I’m very much concerned. I am ensuring I continue to chase with the doctor as it doesn’t sit well with me unfortunately. When I’m researching online, I am seeing a range of things to be honest.

The thing I would say was at 4 months time he had his first teeth come through, plus he was learning a skill I guess of sitting. This time at 6.5 months his upper teeth started appearing and are still pushing through, and he was learning to crawl. Could be unrelated but not sure.

Has anyone else noticed their baby doing this?
And if so was there any outcome etc?
did they eventually stop?
I’d really appreciate some help as right now my mind isn’t rested. Thanks.

it does not allow me to attach videos but I have included pictures and screen shots of the posture. Arms out (sometimes more than others) legs straight appear quite tense/stiff. Mouth would usually be closed. Head stays up. Looking at me, etc or looking around. the image with a heart was when he was around 4 months old. The others are more recent. Thanks.

Baby/ 7 month old stiffens legs/arms usually grunts.
Baby/ 7 month old stiffens legs/arms usually grunts.
Baby/ 7 month old stiffens legs/arms usually grunts.
Baby/ 7 month old stiffens legs/arms usually grunts.
OP posts:
WorriedMama2025 · 27/12/2025 22:45

My LO does this - among many other concerns

any update with your LO @MAMAJT0

Devilsmommy · 05/01/2026 05:26

I remember mine doing this a lot. To me it looked like he was stretching because his muscles were maybe aching, growing pains. He soon stopped.

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