Making sense of diaper sizes

April 2, 2015
Making sense of diaper sizes

Buying diapers only to discover that you've bought the wrong size for your child can be frustrating. It happens more often than you'd think! So how do you know the right diaper sizes to buy? It's not like you can try them on your baby at the store. Here, some pros offer their advice.

Diaper types and sizes

First of all, it's important to know that unlike baby clothing, diapers are sized by the child's weight, not age. While a box of diapers might say, "Newborn," you'll need to check the weight range on it. "Newborn" for one company might mean "up to 10 pounds," while the next size might be for babies who are 8 to 14 pounds. If your 8-pound newborn is on the hefty side, you might want the size 1 diapers.

"Age has little to do with diaper size," explains Robyn Mermelstein, a manager at Hain Celestial, the parent company for baby products company Earth's Best. "Follow the recommended size charts included on most packages to be sure the diaper size is appropriate for the child's weight range." Disposable diaper sizes don't vary much across brands, though you may come to find that some fit your child better than others, especially with older babies.

However, cloth and hybrid diaper sizes will vary. Hybrids have a reusable diaper cover that fits over a cloth diaper or into which you can insert a disposable liner. The diaper cover of the hybrid fits much like a disposable diaper, but according to Victoria Sloane, a mom of three from Chicago who has used all diaper types, finding the correct size takes time. "With the hybrid diapers, I had to play around with sizes and inserts," she says. Purchasing various sizes of diaper covers and inserts will give you room in which to work.

To make sense of diaper sizes, first decide what type of diaper you want to use -- disposable, cloth or hybrid. Then check your baby's weight.

Proper fit

Knowing your baby's weight takes the guesswork out of your diaper search. Use the weight taken at your baby's most recent pediatrician check-up, or, as Jennifer Taylor, founder of Mom Tricks, suggests, step on a scale while holding your baby and make a note of the weight, then weigh yourself alone and calculate the difference. Don't buy large quantities of diapers until you know the size you need. If you buy the wrong size, store the larger ones for when your baby grows and give the smaller ones to a friend or donate them to a local women's shelter.

To determine proper fit, check to see if the diaper is tight around the legs and waist. "Put your finger between the diaper and your baby's leg and then lift the diaper slightly," Taylor suggests. "The diaper should have some give, meaning the elastic isn't too tight. Also, the top of the diaper where the fasteners meet should be about two inches below your baby's belly button -- any more than that means it's too small."

The diaper shouldn't be so snug that it leaves red marks on the skin. Even if the fit appears fine, she says, "if you have to struggle to apply the fasteners to the middle of the diaper, it's probably too small." Also be sure the diaper isn't too snug around the baby's bottom. Taylor also explains, "You should be able to easily put a finger in the waistband without much struggle. ... A properly fitting diaper will be loose in the body but tight enough in the legs and waist."

Wrong fit

Besides being too tight or too low, another sign of a wrong-sized diaper is leakage. Snugness is necessary to avoid leakage, Karen Amidon, owner of the cloth diaper company GreenMountain Diapers, emphasizes. For those parents who want a demonstration of the proper fit of a cloth diaper, the Green Mountain's website has photographs. "When you get a leak at a point when it wouldn't have leaked before, this means that more absorbency is needed," says Amidon.

Nicole Mertes, a mom of five from Utica, Illinois, agrees that sometimes leakage indicates you need to change to a new diaper size. "During the daytime, if the diaper leaked too often, we took that as a hint that it was time to move up," she says. "My youngest had a much greater fluid intake during the day, so we also had to seek a specific nighttime diaper to avoid morning wetness." Extra absorbent diapers or insert liners in the next size up may help avoid such leakage.

As you become experienced at changing diapers -- up to 10 times a day! -- you, too, will learn what works best for your baby and become a pro.

Tips and stories from parents and caregivers who’ve been there.

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