Why Is Your Newborn Sweating at Night? The Multi-Layer Muslin Blanket Fix

Why newborns overheat so easily

A newborn's body is still learning to regulate its own temperature. Their sweat glands are not fully mature, so instead of cooling down efficiently the way an older child does, they tend to just get hotter and more unsettled. This is also why the classic hands-and-feet check is unreliable - a baby's hands and feet are often cool even when their core is overheating. The better check is the back of the neck or the chest.

Common signs your baby is too warm: damp hair at the nape of the neck, flushed cheeks, rapid or noisy breathing, restlessness that does not settle with feeding, and small red bumps (prickly heat) across the neck, chest, or back.

Where the usual fixes fall short

• Cranking the AC and using the same blanket anyway. A cold room does not help if the quilt on top is synthetic and traps heat and moisture against the skin. Crib-level temperature is also often warmer than the thermostat reading, especially if the AC cycles off overnight or there is a power cut.
• One thin cotton sheet, all year. Breathable, but not warm enough on AC nights or through the November to February months, so parents end up piling on mismatched shawls and towels that bunch up under the baby - not something you want near a newborn's face.
• Thick synthetic quilts and comforters. These trap body heat and moisture instead of letting it escape, are harder to wash daily (which matters given how often newborns spit up or leak), and some use dyes that are not meant to sit against infant skin for hours.

What actually works: layers, not one thick blanket

Muslin cotton is a loosely woven, breathable fabric that lets air move through instead of trapping it - it is the same reason muslin is used for swaddles and burp cloths. A single muslin layer is light; stacked in multiple layers, it becomes warm without losing breathability, and you can add or remove a layer as the room temperature changes through the night, instead of switching blankets entirely. Sunshinebaby's newborn essentials collection is built around this exact layering idea rather than one-size-fits-all blankets.

This is also why layer count matters more than blanket thickness. An 8-layer muslin blanket in a smaller size works well for a newborn who needs to be swaddled snugly, while a 6-layer blanket in a larger size gives an older baby or toddler more room to move while still keeping the breathability.

What to actually check before buying one

• 100% pure cotton, nothing blended in. Blends trap more heat than they should.
• Dye certification. Look for Azo-free dyes, ideally certified by a recognised textile body - this matters because a newborn's skin absorbs more than an adult's, and harsh dyes are a common, avoidable source of irritation.
• Layer options for different seasons, so you are not buying a separate blanket every time the weather changes.
• Machine washable, because a newborn's bedding realistically needs washing every few days.

Sunshinebaby's multi-layer muslin cotton blanket checks these boxes directly - 100% pure cotton, Azo-free dyes certified by the Textile Committee of India, and a choice between an 8-layer 120x120cm size (suited up to around age 3) and a 6-layer 140x180cm size (suited up to around age 7), so the same idea scales with your child instead of needing a replacement every year.

A simple bedtime check

Before you decide the AC needs adjusting, feel the back of your baby's neck or chest. Warm and slightly damp means remove a layer. Cool and dry, with no sweating, is about right. Dress your baby in roughly one layer more than you are comfortable in yourself, and let the blanket do the fine-tuning rather than the thermostat alone. Keep any loose bedding away from your baby's face and follow standard safe-sleep spacing, regardless of which blanket you use. If you are shopping for one, this multi-layer muslin blanket is the one we would start with.