What are the key developmental milestones for infants up to 10 months old?

Developmental Milestones Up to 10 Months

By 9-10 months, infants should roll to both sides, sit well without support, demonstrate motor symmetry, reach for and transfer cubes, rake small objects with 4 fingers, and pick up small objects with 3 fingers. 1

Gross Motor Milestones by Age

2 Months

• Lifts head and chest when lying on stomach (prone position) 1

4 Months

• Rolls over from stomach to back (prone to supine) 1
• Supports weight on elbows and wrists when on stomach 1
• Hands should be unfisted and playing with fingers at midline 1
• Grasps objects 1

6 Months

• Should have achieved rolling and pulling hands above head 2
• Transfers objects between hands 2

9 Months (Critical Checkpoint)

• Rolls to both sides 1
• Sits without support 1
• Demonstrates motor symmetry (uses both sides of body equally) 1
• Pulls to stand 1
• Comes to sit from lying position 1
• Crawls 1

Fine Motor Milestones by Age

4 Months

• Hands unfisted 1
• Plays with fingers in midline 1
• Grasps objects 1

9 Months

• Reaches for cubes and transfers them between hands 1
• Rakes small objects with 4 fingers 1
• Picks up small objects with 3 fingers (not yet the 2-finger pincer grasp, which emerges at 12 months) 1, 2

Red Flags Requiring Immediate Attention

At 9 Months Visit

The absence of these skills signifies delay and warrants evaluation:

• Inability to roll to both sides 1
• Cannot sit well without support 1
• Lack of motor symmetry (asymmetric movement patterns may indicate unilateral cerebral palsy) 1, 2

Progressive Concerns

• Loss of previously acquired skills at any age requires immediate evaluation for progressive neuromuscular disorders 1, 2
• Marked delay beyond the mean ages listed warrants attention, though does not necessarily signify neuromotor disease 1

Surveillance Schedule

Continuous developmental surveillance should occur throughout infancy, with formal assessment at the 9-month visit and reevaluation at 3- to 6-month intervals if concerns exist. 1

• The 9-month visit specifically evaluates rolling, sitting, motor symmetry, reaching, transferring, and raking/grasping skills 1
• Additional screenings should be performed whenever concerns are raised by parents or healthcare professionals 1
• Early identification of delays allows for referral to therapeutic services and improves developmental outcomes 3

Important Clinical Considerations

Preterm Infants

• Use corrected age (from due date rather than birth date) for the first 24-36 months when comparing to developmental norms 3
• Preterm infants have higher risk of visual and hearing impairments requiring specific attention to sensory function 3

Natural Variation

• These milestones represent mean ages when typically developing children achieve skills 1
• Approximately 75% or more of children should achieve these milestones by the stated ages 4
• Some variation is normal, but marked delays warrant evaluation rather than a "wait-and-see" approach 4