Beyond the Flat: Why Upright Seating Matters After 6 Months

London, 20 October 2025 — Parents love the convenience of lie-flat strollers for newborns. But once babies reach around six months, experts agree they benefit far more from upright or semi-reclined seating (approximately 100°–120°) that supports their physical strength, posture, and curiosity about the world.

“After six months, babies aren’t just along for the ride—they’re active passengers,” said Sandra Incendiario, Child Development Advisor at Parent Studio. “A semi-upright position helps them build core muscles, stay engaged with their surroundings, and maintain a natural spinal curve—all while remaining safe and comfortable. Flat is fantastic for newborns; forward is better for explorers.”

The Developmental Shift at 6 Months

By about six months, most babies can:

• Hold their head up steadily
• Sit with support or begin sitting unassisted
• Engage visually and socially with the world around them

Keeping babies flat for long periods after this stage can:

• Limit core and neck muscle development
• Slow milestones like sitting and crawling
• Reduce stimulation and social interaction

Why Upright (or Semi-Reclined) Supports Growth

A semi-reclined or upright stroller seat:

• Supports the natural spinal curvature without forcing a rigid posture (when the harness is properly adjusted)
• Encourages core and muscle strength
• Prevents slumping often seen with fully upright 90° seats or poorly adjusted harnesses
• Promotes visual exploration and engagement, aiding cognitive development

Medical guidance commonly recommends a recline angle of ~100°–120° for babies 6+ months.

Why Lie-Flat Isn’t Ideal After 6 Months

Once babies can sit and hold their head up, a fully flat position:

• Doesn’t challenge the muscles needed for sitting and movement
• Restricts the visual field and can frustrate curious, alert infants
• May slow milestone progression

Even for naps, most stroller seats for 6+ months do not need to go fully flat. A slight recline keeps the child secure in the harness, supports their natural spinal curve, and maintains a safe, comfortable posture.

What Parents Should Look For

Choose a stroller that grows with your child, offering:

• Multiple, easily adjustable recline positions
• Ergonomic, supportive seating and a properly adjustable harness
• Options for upright exploration and gentle recline for rest

Models like the Stokke YOYO³ offer adjustable seating angles that support healthy development beyond six months. As children grow, they begin to develop a slight hollow in the lower back; a more upright, supportive backrest encourages proper posture and long-term comfort.

Key Takeaways

• Lie-flat = best for newborns (0–6 months) for airway safety and spinal support.
• Semi-upright (100°–120°) = best for 6+ months for muscle, motor, and social development.
• For naps, a slight recline (not fully flat) keeps babies safe, supported, and comfortable.
• Support the stage they’re in—not the one they’ve outgrown.

“Think of it like upgrading from ‘carriage’ mode to ‘co-pilot’ mode,” added Sandra Incendiario. “Upright seating helps little bodies get stronger and little minds get brighter.”

About Parent Studio

Parent Studio is a London-based baby and parenting destination offering curated products, expert guidance, and hands-on education for families. We focus on solutions that evolve with your child’s development—because smarter choices today mean happier journeys tomorrow. Learn more at parentstudio.co.uk.

Media Contact

Brent Grung
Parent Studio
Email: marketing@parentstudio.co.uk
Phone: +44 (0)20 4603 5758

Notes to editors: Always follow manufacturer instructions for harness adjustment and recline use. Parents and caregivers should consult their paediatric professional with any individual health concerns.