Baby Milestones: First Four Months

Neonatal Period to 4 Months Developmental Milestones

• Prone (on stomach): Lies in flexed posture; turns head side to side; head sags when held ventrally.
• Supine (on back): Generally flexed and a bit stiff.
• Visual: May fixate on a face or light within line of vision; "doll’s eye" movements (eyes move when head turns).
• Reflexes: Active Moro (startle) reflex, stepping and placing, grasp reflex active.
• Social: Visual preference for human face.

• Prone: Legs more extended; holds chin up; turns head; briefly lifts head to body plane when held face down.
• Supine: Shows tonic neck posture; is supple and relaxed; head lags when pulled to sitting position.
• Visual: Watches people; follows moving objects.
• Social: Moves body in rhythm with voice during social interaction; beginning to smile.

• Prone: Raises head slightly farther; maintains head in line with body when held face down.
• Supine: Tonic neck posture predominates; head still lags when pulled to sitting.
• Visual: Follows moving object across 180 degrees.
• Social: Smiles during social contact; listens to voices and coos (makes vowel sounds).

• Prone: Lifts head and chest with arms extended; head held above body line when held ventrally.
• Supine: Tonic neck posture predominates; reaches out toward objects but may miss; waves at a toy.
• Sitting: Head lag is less when pulled to sitting; early head control with bobbing; back rounded.
• Reflex: Moro reflex diminishes; makes defensive or selective withdrawal movements.
• Social: Sustained social interaction; listens to music; vocalizes sounds like "aah" or "ngah."

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• Prone: Lifts head and chest with head approximately vertical; legs extended.
• Supine: Symmetric posture; hands midline; reaches for and grasps objects, bringing them to mouth.
• Sitting: No head lag when pulled to sit; head steady, tilted forward; enjoys sitting with full trunk support.
• Standing: When held upright, pushes with feet.
• Adaptive: Sees small objects (like a raisin) but may not reach for it yet.
• Social: Laughs out loud; may show displeasure if social contact is abruptly broken; excited at sight of food.

Additional Notes on Development

• By 2 months old, infants begin to discriminate rhythmic speech patterns and can actively seek stimuli.
• At around 3-4 months, infants become more interactive socially, cooing and engaging in vocal turn-taking with parents.
• These months are crucial for developing head control, visual tracking, social smiling, and early motor skills like reaching and grasping objects.

These milestones reflect typical neurologic maturation, sensory development, motor control, and social/emotional growth expected during the first four months of life.