What are the best strategies for sleep training a 20-month-old child?

Sleep Training a 20-Month-Old Child

Establish a consistent bedtime routine performed at the same time every night, which has been proven to reduce sleep onset latency, decrease night wakings, and improve overall sleep duration in young children. 1, 2, 3

Core Sleep Requirements at 20 Months

• Children aged 1-2 years require 11-14 hours of total sleep per 24 hours (including naps) to promote optimal health, attention, behavior, learning, and emotional regulation 4
• At this age, sleep should be consolidating toward 10-12 hours of nighttime sleep with 1-2 shorter daytime naps totaling 2-3 hours 5

Essential Components of the Bedtime Routine

Implement these activities in the same sequence at the same time every evening:

• Warm bath 90 minutes before target bedtime to facilitate the natural drop in core body temperature that promotes sleep 1
• Calming activities such as gentle massage, quiet reading, or lullabies performed in dim lighting 1, 2
• Consistent bedtime and wake time maintained 7 days per week, regardless of how much sleep was obtained the previous night—this is critical for circadian rhythm stability 5, 1
• Total routine duration should be 20-30 minutes and end with the child being placed in bed drowsy but awake 1, 2

The evidence is particularly strong here: a dose-dependent relationship exists where more consistent implementation of bedtime routines correlates with better sleep outcomes, including earlier bedtimes (average 30 minutes earlier), shorter sleep onset latency (reduced by 15-20 minutes), and fewer night wakings 3. This benefit was demonstrated across 10,085 children globally and holds true regardless of cultural background 3.

Critical Stimulus Control Principles

These environmental modifications are non-negotiable for successful sleep training:

• Use the bedroom only for sleep—no play, television, or stimulating activities in the sleep space 1, 6
• Put the child to bed drowsy but awake rather than fully asleep to establish independent sleep initiation skills 1, 7
• Maintain a 12-hour light/12-hour dark schedule: expose to bright light during daytime hours and ensure complete darkness at night to support circadian rhythm consolidation 1, 7
• Keep the sleep environment dark, quiet, cool, and free from screens 5, 1
• Ensure presence of security objects (blankets, stuffed animals) that provide comfort 5

Behavioral Sleep Training Methods

If the bedtime routine alone does not resolve sleep problems within 2-3 weeks, implement graduated extinction:

• Place the child in bed at the designated bedtime while drowsy but awake 1
• Leave the room and wait progressively longer intervals (3,5,10,15 minutes) before briefly checking on the child 6
• Keep check-ins brief (30-60 seconds), boring, and without picking up the child 6
• Gradually increase wait times over successive nights 6

While extinction alone (ignoring all crying) is highly effective, it is difficult for parents to comply with, so graduated extinction represents a reasonable compromise 6. The evidence shows that extinction-based procedures significantly reduce problematic sleep behaviors when implemented consistently 6, 2.

Feeding and Sleep Coordination

At 20 months, nighttime feeding should be eliminated:

• Establish 3 meals and 2-3 snacks during daytime hours at consistent times 5
• No feeding within 30 minutes of bedtime to prevent sleep-feeding associations 5, 7
• If the child wakes at night, do not offer food or milk—this perpetuates the waking pattern 7

Meal timing influences circadian synchronization, and structured daytime feeding patterns (rather than on-demand feeding) promote better nighttime sleep consolidation 5, 7.

What NOT to Do

Avoid these common mistakes that undermine sleep training:

• Never use antihistamines (diphenhydramine/Benadryl) for sleep problems—they lack efficacy data in children, cause problematic side effects, and tolerance develops rapidly 1
• Do not allow inconsistent schedules or variable bedtimes, as every 1 hour increase in sleep timing variability is associated with worse metabolic and behavioral outcomes 5
• Eliminate all screen time for at least 2 hours before bedtime—screens interfere with melatonin production and delay sleep onset 5, 1
• Do not engage in stimulating play or activities after the bedtime routine begins 5, 1
• Avoid co-sleeping or bringing the child into the parent's bed when night wakings occur, as this reinforces the waking behavior 6

Common Pitfalls and How to Avoid Them

• Inconsistency between caregivers: All adults in the household must implement the same routine and response to night wakings 6, 2
• Starting the routine too late in the evening: Begin the routine early enough that the child is in bed by 7:00-8:00 PM for optimal circadian alignment 5, 3
• Giving up too soon: Sleep training typically requires 1-2 weeks of consistent implementation before significant improvement is seen 2, 3
• Responding too quickly to night wakings: Wait at least 3-5 minutes before checking to allow the child opportunity to self-soothe 6

When to Escalate Care

Consider referral to a pediatric sleep specialist if:

• Sleep problems persist after 4 weeks of consistent behavioral intervention 5
• The child has loud snoring, gasping, or breathing pauses during sleep (possible sleep-disordered breathing) 5
• Extreme bedtime resistance or night wakings are accompanied by developmental regression or behavioral concerns 5

The evidence for behavioral sleep training at this age is robust, with multiple studies demonstrating significant improvements in sleep onset latency (reduced by 15-30 minutes), night wakings (reduced by 50-70%), and total sleep duration (increased by 30-60 minutes) when consistent routines and extinction-based methods are properly implemented 2, 3.