Setting Up a Safe Sleep Environment: Bare Crib, Firm Mattress, and Nothing Else
No bumpers, pillows, blankets, stuffed animals, or sleep positioners. Why these rules exist and when each item becomes safe.
By TeachToddler Editorial Team · Updated April 11, 2026 · Child Safety
🛏️ The ABCs of Safe Sleep
The AAP's 2022 updated safe sleep guidelines are built around three core principles: Alone, Back, Crib. Following these three rules for every sleep — naps and nighttime — is the single most effective thing you can do to reduce the risk of SIDS and other sleep-related infant deaths.
- Alone: Baby sleeps alone in their own sleep space. No other people, no pets, no pillows, no blankets, no stuffed animals, no crib bumpers (including mesh bumpers), and no sleep positioners
- Back: Place baby on their back for every sleep until their first birthday. Side sleeping is not safe — babies placed on their side can roll onto their stomach. Once a baby can roll both ways on their own, you do not need to reposition them if they roll during sleep
- Crib: Use a safety-approved crib, bassinet, or play yard with a firm, flat mattress. The only thing on the mattress should be a single tight-fitting sheet
- This applies to every sleep — nighttime, nap time, at grandma's house, at daycare, and while traveling
🧱 The Mattress: Firm and Flat
The crib mattress is the foundation of safe sleep. A mattress that is too soft, too thick, or not flat creates a suffocation risk — a baby's face can sink into a soft surface and block their airway.
- Firm mattress test: Press your hand into the center of the mattress and release. It should snap back immediately and not hold the impression of your hand. If it does, it's too soft
- The mattress must be designed specifically for the crib or bassinet and fit snugly. If you can fit more than two fingers between the mattress edge and the crib wall, the mattress is too small
- Do not add mattress toppers, memory foam pads, egg crate foam, or extra padding of any kind
- Use only a single fitted sheet designed for the specific mattress size — no loose sheets, no blankets tucked under the mattress
- Do not use a second-hand mattress unless you know its full history. A mattress that has been recalled, damaged, or has a broken-down inner structure is not safe
Room Temperature: Keep the baby's room between 68°F and 72°F (20–22°C). Overheating is a SIDS risk factor. Dress your baby in a single layer of sleep clothing or a wearable blanket (sleep sack). Feel the back of their neck — if it's hot or sweaty, remove a layer. The room should feel comfortable to you in a short-sleeved shirt.
🚫 What Does NOT Belong in the Crib
Many items marketed to parents as "safe sleep" products are actually dangerous. The crib should be completely bare except for the fitted sheet and the baby. Here's what to keep out and why.
- Crib bumpers (including mesh ones): Bumpers have been linked to suffocation, strangulation, and entrapment deaths. Mesh bumpers can still detach and cover a baby's face. They're banned for sale in many states
- Blankets and quilts: A loose blanket can cover a baby's face and block their airway. Use a wearable blanket (sleep sack) instead. Blankets can be introduced after 12 months
- Pillows: Not needed and create a suffocation risk. Babies don't need head support — a firm flat mattress is ideal for their developing spine
- Stuffed animals and toys: Keep all soft objects out of the crib until at least 12 months
- Sleep positioners and wedges: The FDA has warned against these products. They can cause suffocation if a baby rolls against or on top of them. No device marketed to "prevent SIDS" or "keep baby on their back" is approved by the AAP
- Dock-a-Tot, Snuggle Me, and similar loungers: These are not approved for unsupervised sleep. The soft, padded sides create a suffocation hazard
🏠 Room-Sharing (Not Bed-Sharing)
The AAP recommends that your baby sleep in the same room as you — but on a separate, firm, flat surface — for at least the first 6 months and ideally up to 12 months. Room-sharing reduces SIDS risk by up to 50%. Bed-sharing (sleeping in the same bed as your baby) is not the same thing and is not recommended.
- Place the crib or bassinet within arm's reach of your bed so you can monitor and breastfeed without fully bed-sharing
- Bed-sharing risks: An adult or older child can roll onto the baby. Pillows, blankets, and soft mattresses create suffocation hazards. The gap between the mattress and headboard/wall can trap a baby
- Bed-sharing is especially dangerous if either parent smokes, has consumed alcohol, has taken sedating medication, or if the sleeping surface is a couch, recliner, or waterbed
- If you fall asleep while feeding in bed, the safest thing to do when you wake up is to move the baby back to their own sleep surface immediately
- Couches and recliners are the single most dangerous places for a baby to sleep — the risk of sleep-related death is 50 to 67 times higher on a couch
✅ Factors That Reduce SIDS Risk
In addition to the ABCs, several specific practices have been shown to reduce the risk of SIDS.
- Pacifier at sleep time: Offering a pacifier at naps and bedtime reduces SIDS risk, even if the pacifier falls out after the baby falls asleep. If breastfeeding, wait until nursing is well established (about 3–4 weeks) before introducing a pacifier. Don't force it if the baby refuses
- Fan in the room: A study found that a fan running in the baby's sleep area reduced SIDS risk by 72%. The fan improves air circulation and prevents rebreathing of exhaled CO2. Point the fan at the wall or ceiling — not directly at the baby
- Breastfeeding: Any breastfeeding reduces SIDS risk. Exclusive breastfeeding for 6 months provides the greatest protection, but any amount of breastfeeding helps
- Swaddling (with caution): Swaddling can calm a newborn and improve sleep, but stop swaddling the moment your baby shows signs of rolling — even if they haven't fully rolled yet. A swaddled baby who rolls face-down cannot use their arms to push up. Always swaddle with arms tight but hips loose
- Immunizations: Keeping up with the recommended vaccination schedule has been associated with a 50% reduction in SIDS risk
- Smoke-free environment: Do not smoke during pregnancy or after birth. Do not allow anyone to smoke near the baby. Secondhand and thirdhand smoke exposure are significant SIDS risk factors
📋 Safe Sleep Setup Checklist
Set up the sleep space before the baby arrives and make sure every caregiver — partner, grandparent, babysitter, daycare — follows the same rules for every sleep.
- ✅ Firm, flat, safety-approved crib mattress that fits snugly in the crib
- ✅ Single tight-fitting sheet — nothing else on the mattress
- ✅ No bumpers, pillows, blankets, stuffed animals, toys, or positioners in the crib
- ✅ Baby placed on their back for every sleep
- ✅ Crib in the parents' room for at least the first 6 months
- ✅ Room temperature 68–72°F with a fan running (pointed at wall/ceiling)
- ✅ Baby dressed in a sleep sack or single layer — no loose blankets
- ✅ Pacifier offered at sleep time
- ✅ No smoking in the home or around the baby
- ✅ Swaddling stopped at the first sign of rolling
- ✅ Baby never left to sleep on a couch, recliner, swing, bouncer, or car seat