Low Muscle Tone (Hypotonia)
The short answer
Low muscle tone means your baby's muscles feel less firm or their body feels "floppy" when you hold them. While it can sometimes indicate an underlying condition, many babies with mildly low tone do very well with support and strengthening activities.
By Age
What to expect by age
All newborns have relatively low tone compared to older babies, and they naturally curl into a flexed position. Premature babies especially may feel floppier than full-term babies. Head lag when gently pulling your baby from lying to sitting is normal at this age, though they should show some effort to keep their head in line.
Babies are developing head control and should be starting to hold their head steadily when supported upright. During tummy time, they should be beginning to lift their head and push up on their forearms. If your baby seems unable to make progress with head lifting or feels unusually floppy, it is worth mentioning to your doctor.
By now, babies typically have good head control and are working on sitting with support. Babies with low tone may need more practice and encouragement during tummy time and supported sitting. Some babies with mild low tone begin to "catch up" around this age as they build strength.
Most babies are sitting independently and some are beginning to crawl. Babies with low muscle tone may reach these milestones a bit later, which is often manageable with physiotherapy support. Your doctor can help assess whether the tone difference is mild and isolated or part of a broader pattern.
Babies with benign low tone are often making good progress by this point, especially if they have had support from a physiotherapist. They may pull to stand and cruise a little later than average. Ongoing gentle strengthening through play continues to be helpful.
What Should You Do?
When to take action
- Your baby feels a bit "softer" than other babies but is still meeting motor milestones within a reasonable range
- Your premature baby has lower tone that is gradually improving as they grow
- Your baby has mild low tone but is making steady progress with head control, rolling, and sitting
- There is a family pattern of being more flexible or "double-jointed," and your baby is developing well overall
- Your baby seems noticeably floppier than other babies their age and is slow to develop head control
- Your baby has difficulty with tummy time even with lots of practice and support, and does not seem to be building strength
- Motor milestones like rolling, sitting, and reaching seem significantly delayed alongside the low tone
- Your baby tires very quickly during physical activities like tummy time or supported sitting
- Your baby feels suddenly more floppy than usual, seems less responsive, or has a significant change in their tone or alertness
- Your baby has difficulty feeding, a weak cry, and very low muscle tone, particularly in the newborn period
- Your baby has low tone combined with breathing difficulties or failure to thrive
Sources
Related Resources
Related Physical Concerns
My Baby Seems to Use One Side More Than the Other
Babies should use both sides of their body fairly equally during the first 18 months of life. While slight preferences can be normal, a consistent pattern of favoring one side - using one arm much more than the other, crawling with one leg dragging, or turning the head predominantly one way - should always be discussed with your pediatrician. Early identification of asymmetry leads to the best outcomes.
My Baby Curls Their Toes
Toe curling is very common in babies and is usually caused by the plantar grasp reflex, which is a normal newborn reflex that causes toes to curl when the sole of the foot is touched. This reflex typically fades by 9-12 months. Occasional toe curling during standing or walking is also normal as babies figure out their balance. Persistent, tight toe curling past 12 months may warrant a mention to your pediatrician.
My Baby Favors One Leg
Babies should use both legs roughly equally when kicking, crawling, and eventually walking. If your baby consistently favors one leg or seems to avoid using the other, it is worth having your pediatrician take a look. The cause is often something simple and treatable, like a minor hip or muscle issue, but early evaluation helps ensure the best outcome.
My Baby Gets Hiccups a Lot
Hiccups are extremely common in babies, especially newborns, and are almost always completely harmless. They happen because your baby's diaphragm is still developing and gets a little jumpy when their tiny stomach fills up or air gets swallowed. Most babies outgrow frequent hiccupping by 6-9 months.
My Baby Has Jerky Movements
Newborns and young babies often have jerky, uncoordinated movements because their nervous systems are still developing. What looks like random flailing is actually your baby learning how their body works. These movements typically become smoother and more controlled by 3-4 months as motor skills mature.
Baby Not Bearing Weight on Arms
Bearing weight on the arms is a gradual skill that develops during the first 6 months. Babies first prop up on their forearms around 2 to 4 months, then progress to pushing up on extended arms by 5 to 6 months. Regular tummy time is the best way to build this strength, even if your baby protests at first.