My Baby Keeps Breaking Out in Rashes: What's Really in Your Baby's Clothes

Where clothing-related rashes actually show up

Location tells you a lot. A rash that follows the diaper's edge is almost always diaper rash, not clothing. A rash at the neckline, waistband, underarms, or anywhere a seam or tag sits against the skin is a strong sign the clothing itself is the trigger. Heat rash, by contrast, tends to cluster on the neck, chest, and back regardless of what your baby is wearing, and usually improves once the layers come off.

What's usually causing it

• Synthetic or blended fabric that doesn't breathe. Trapped sweat against the skin for hours is enough to irritate a newborn's still-developing skin barrier.
• Non-certified dyes and finishing chemicals. Cheaper baby clothing is sometimes treated with dyes or wrinkle-resistant finishes that are not tested or certified for infant skin contact, and these do not always wash out completely on the first try.
• Rough seams, tags, and hardware. A stiff tag or a metal snap sitting directly against sensitive skin for hours is a simple, physical irritant that has nothing to do with chemicals at all.

The fixes that only half-work

Switching detergent helps when the detergent really is the trigger, but if the fabric or dye is the actual cause, a gentler detergent will not stop the reaction. Washing new clothes once before the first wear reduces surface residue but does not remove finishing chemicals that are baked into the fibre. A barrier cream treats the symptom on the skin, not the fabric causing it.

What actually solves it: certified organic cotton

GOTS (Global Organic Textile Standard) certification means the fabric is checked at every stage, the fibre, the dye, and the finishing process, not just the final colour. That is a meaningfully higher bar than a garment simply being labelled "cotton." Muslin cotton specifically is a loosely woven fabric that lets air move through it, which matters because trapped heat and moisture against the skin is one of the most common everyday triggers for baby rashes.

Sunshinebaby's organic muslin cotton range is GOTS-certified and uses eco-friendly snap closures instead of rough plastic or metal hardware, which removes two of the most common physical irritants at once.

What to look for when you're buying

• GOTS certification, not just a "100% cotton" label on the front of the pack.
• A loose, breathable weave like muslin, especially for anything worn against the skin for hours (rompers, onesies, swaddles).
• Soft closures - snap buttons rather than sharp studs or rough zips.
• A short wash-and-wear history from the brand, so you are not the one discovering issues.

Sunshinebaby's organic muslin cotton romper is a straightforward example - 100% GOTS-certified cotton, eco-friendly front buttons, and snap-closure legs that make diaper changes easier without adding rough hardware near the skin.

How to check if it's really the clothes

Remove the suspected item for two to three days and watch whether the rash clears. If it does, reintroduce it briefly and see whether the rash returns - that pattern is a strong confirmation. See your pediatrician if the rash spreads, oozes, blisters, comes with a fever, or does not improve after you have removed the likely fabric.

If you are shopping for a safer everyday romper, this organic muslin romper is the one we would start with.