A pediatrician with over 20 years of experience. General pediatrics and pediatric pulmonary medicine training at the Boston Children’s Hospital. BS - Yale University; MD and PhD - Columbia University.
Why it's useful
Many baby articles of clothing have more than one common name. Onesies and bodysuits are essentially the same thing. We'll call them onesies here.
Onesies look like a short- or long-sleeved shirt with snap openings at the bottom so they don't ride up while providing easy access to the diaper.
Onesies are great for newborns because they ensure only smooth material near the umbilical cord (no waistband from pants); however, you can always opt for a diaper plus a T-shirt.
Your baby can comfortably wear onesies all day long, if so you choose. On chillier days, you can pair them with pants and socks. Onesies are also great as your baby gets older because they allow their legs to move freely for playing, kicking, rolling, and eventually crawling.
What to consider
GOTS or OEKO-TEX certification: We only carry GOTS or OEKO-TEX certified onesies made from natural materials to minimize the risk of dermal exposure to harsh chemicals. Read more here.
Important! We recommend pre-washing all textile baby items before using to minimize the chance that any residual chemicals or packing dust don’t irritate your baby’s skin.
Babies, especially young ones, often dislike clothes going over their head, and it can be really hard to put things on newborns with very little neck and body strength. Therefore, for younger babies, choosing a kimono-style onesies with side snaps, or a onesie with front snaps that make the neck open very wide, can make your life much easier and keep your baby happy.
Make sure that the onesie isn’t too tight, as tight-fitting baby clothes can cause skin irritation, rashes, and even digestive issues.
Depending on the weather, you can choose long or short sleeves.
Have fun with colors and patterns!
How many to get
For each size, you need approximately 1-2 onesies or sleepers per day; there will be days when you go through more. That means that if you do laundry once a week, you need 7-14. If you have the budget, it might make things easier to purchase in the middle to high end of that range, especially when your baby has just arrived. You can adjust the number when you size up if you find yourself doing laundry more frequently than you expected.
For sizing, start with size 0-3 months. If your baby arrives early, you may have to order a few preemie pieces. You may also want to have a few 3-6 month pieces just in case you have a large newborn or a fast grower.
Remember that you won't know your baby's growth trajectory until they’re here, so don't buy too many larger sizes (6 mo+) as you might end up with the wrong size for the season.
Leleki does not provide medical advice, diagnosis, or treatment. The resources on our website are provided for informational purposes only. You should always consult with your care provider / a healthcare professional if you have any questions or concerns.
Onesies / bodysuits
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