What Do Infants Wear To Sleep

Figuring out what do infants wear to sleep is one of the most common and important questions for new parents. Getting it right is crucial for your baby’s safety and comfort, and it can help everyone get more rest.

This guide will walk you through everything you need to know, from basic rules to seasonal adjustments. We’ll cover safe fabrics, how to check if your baby is too hot or cold, and what to avoid. Let’s make sure your little one is dressed perfectly for a safe and sound night’s sleep.

This is the core question. The American Academy of Pediatrics (AAP) and other safety organizations are clear: the safest thing for a baby to wear to sleep is a wearable blanket or sleep sack. These are designed to replace loose blankets in the crib, which are a suffocation risk.

Footed pajamas or a onesie underneath the sleep sack is usually perfect. The key is to dress your baby in one more layer than you would be comfortable wearing in the same room. Always prioritize safe sleep practices above all else.

The Golden Rule: TOG Ratings Explained

You might see sleepwear labeled with a “TOG” rating. This measures thermal overall grade, or how warm the garment is. Understanding this helps you choose the right sleep sack for the temperature.

TOG 0.5: Very lightweight for warm summer nights (over 75°F / 24°C).
TOG 1.0: Ideal for standard room temperatures (68-72°F / 20-22°C). This is the most common.
TOG 2.5: For cooler rooms (61-68°F / 16-20°C).
TOG 3.5: Very warm, usually for unheated rooms in winter.

Matching the TOG to your room’s temperature is the best way to ensure comfort. A simple room thermometer is a great investment for your nursery.

How to Check Your Baby’s Temperature

Forget feeling hands and feet! A baby’s extremities are often cool too the touch. The best way to check their core temperature is to feel the back of their neck or their chest.

Just Right: The skin feels warm and dry.
Too Hot: The skin feels hot, clammy, or sweaty. Your baby’s face may be flushed.
Too Cold: The skin feels cool to the touch. Your baby may be unusually fussy.

If your baby is too warm, remove a layer. If they’re cool, add one. It’s better to use layers of light clothing than one heavy item.

Safe Sleepwear Fabrics and Features

Choosing the right material is just as important as the style. Always opt for breathable, natural fabrics whenever possible.

Cotton: The gold standard. It’s breathable, soft, and easy to wash. Look for 100% cotton, especially for sensitive skin.
Bamboo: Naturally temperature-regulating, moisture-wicking, and very soft. A great option for babies with excema.
Muslin: A lightweight, woven cotton that gets softer with each wash. Perfect for summer sleep sacks and swaddles.
Organic Fabrics: A good choice if you’re concerned about chemical pesticides used in conventional cotton farming.

Avoid these features for sleep: Loose strings, ribbons, hoods (on sleepwear for bed), or any overly loose fabric that could cover the face. Snaps and zippers should be covered or designed not to irritate skin.

The Swaddle Transition

Newborns often sleep better when swaddled, as it mimics the snug feeling of the womb. However, once your baby shows signs of trying to roll over (usually around 2-4 months), you must stop swaddling immediately.

The transition can be tricky. Here’s a simple step-by-step approach:

Start with one arm out of the swaddle for a few nights.
Then, move to both arms out, but keep the swaddle snug around the chest.
Finally, switch to a wearable sleep sack with arm holes. This keeps them warm without restricting their arms, which they need for safe rolling.

Season-by-Season Sleepwear Guide

What your baby wears changes with the weather. Here’s a breakdown for each season.

Summer Sleep (Warm & Hot Nights)

The goal is too keep baby cool and prevent overheating. Dress them minimally.

A short-sleeve onesie or just a diaper inside a very lightweight (0.5 TOG) muslin or cotton sleep sack.
Use a fan in the room (pointed at a wall, not directly at the crib) to circulate air.
If it’s extremely hot, a diaper alone may be sufficient, but monitor temperature closely.

Winter Sleep (Cold Nights)

Layering is your friend, but avoid bulky items that can ride up.

Start with a long-sleeve bodysuit or footed pajamas.
Add a heavier sleep sack (2.5 TOG or higher) rated for the temperature of your room.
Never use a hat for sleep indoors, as babies release excess heat from their heads and it can lead to overheating.
Skip blankets, quilts, and sheepskins in the crib.

Spring & Fall (Variable Temperatures)

These seasons can be unpredictable. The layered approach works best.

A medium-weight footed sleeper is a good base.
Have a 1.0 TOG sleep sack ready for standard nights, and a 2.5 TOG sack handy for unexpectedly chilly nights.
Check your baby’s temperature during the night if the weather shifts dramatically.

Common Mistakes to Avoid

Even with the best intentions, it’s easy to make errors. Here’s what too watch out for.

Overbundling: This is the most common mistake. Overheating is a risk factor for SIDS. Remember the “one more layer” rule.
Using Loose Blankets: Blankets, quilts, and loveys should not be in the crib until after the first birthday, at minimum.
Putting on a Hat Indoors: As mentioned, hats for sleep can cause overheating.
Choosing the Wrong Size: Sleepwear should be snug-fitting but not tight. Avoid baggy pajamas that could bunch up around the face.
Ignoring the Room Temperature: Don’t just dress for the season; dress for the actual temperature of your baby’s room.

Special Considerations

Some situations require extra thought.

For Preemies

Premature babies often have trouble regulating their body temperature. They may need an extra layer compared to a full-term baby. Always follow the guidance of your neonatal team and use a preemie-sized sleep sack designed for their tiny size.

Baby’s with Eczema or Sensitive Skin

Choose 100% cotton or bamboo fabrics, which are gentle and breathable. Avoid synthetic materials like polyester, which can trap heat and irritate skin. Wash all new sleepwear before use with a fragrance-free, hypoallergenic detergent.

Diaper Changes

Opt for sleepwear that makes nighttime changes easy. Many sleep sacks have a two-way zipper that opens from the bottom, or snaps at the legs. This allows you to change a diaper without fully undressing your baby or removing the sleep sack, helping them stay sleepy.

Putting It All Together: A Simple Checklist

Before you put your baby down for the night, run through this list.

Check the room thermometer. What is the actual temperature?
Select a sleep sack with the appropriate TOG rating for that temperature.
Choose a base layer (onesie, footed pajamas) based on the season and sack weight.
Dress your baby. Do a quick neck/chest temperature check.
Place baby on their back in an empty crib (firm mattress, tight-fitting sheet only).
Ensure the sleep sack fits well—snug around the neck and armholes so it can’t slip up.

Following these steps will give you peace of mind and help your infant sleep safely.

FAQ: Your Questions Answered

Can my baby wear a onesie to sleep?

Yes, a onesie can be a perfect base layer under a sleep sack, or even the sole item on a very hot night. Just make sure it’s fitted and not too loose.

What should a newborn wear to sleep?

A newborn can be swaddled in a light muslin or cotton swaddle blanket, or wear a swaddle sack. Over that, dress them according to room temperature—often just a diaper and swaddle is enough. Remember to stop swaddling at the first sign of rolling.

Are footie pajamas warm enough for sleep?

Footed pajamas alone are usually warm enough for a standard room (68-72°F) if made of a medium-weight cotton. In a cooler room, you would add a sleep sack over them. They are a great, safe option because they keep feet covered without loose socks.

How many layers should an infant wear at night?

The general rule is one more layer than you are comfortable wearing. In a 70°F room, if you’re in light pajamas, your baby might need footed pajamas (one layer) plus a light sleep sack (the second, extra layer).

When can babies sleep with a blanket?

The AAP recommends keeping loose blankets, pillows, and soft toys out of the crib until at least 12 months of age. A wearable blanket or sleep sack is the safe alternative until your toddler is ready for a regular bed.

What not to let babies wear to sleep?

Avoid anything with hoods, strings, or loose fabric. Don’t use hats indoors, bulky coats, or any weighted sleepwear or swaddles, as they are not considered safe for infant sleep.

Choosing the right sleepwear is a simple but powerful way to protect your baby. By focusing on safe, breathable layers and using a sleep sack, you create an ideal environment for rest. Trust your instincts, use the touch test, and adjust as needed. With this knowledge, you can feel confident that your little one is dressed for a safe and comfortable night.