While the nappy size may appear to fit your baby, the amount of pee may have increased with his growth, so the nappy may not be able to absorb the larger amount of urine. For disposable nappies, the bigger the size, the better the absorbency.
If the diaper isn't fully covering your baby's bottom, choose a bigger size. If your baby regularly gets diaper rash, it may be because the diaper is too small and doesn't keep the moisture away from their skin. The diaper may be too small if your baby shows signs of distress (for example, pulling at the diaper).
If you can't comfortably fit two fingers under the waistband of the fastened nappy, it's time for a bigger size. You may need to go up a size if you notice red marks on your baby's tummy or thighs when you remove the nappy. If the nappy isn't fully covering your baby's bottom, choose a bigger size.
Bigger nappies are capable of handling more waste as they have more absorbent material. But remember, nappies may also leak because they are too big. Make sure that the nappy fits snuggly around the waist and thighs by running your fingers around the edges and checking that there are no gaps and it fits comfortably.
On the small sizes, we provide the wetness indicator to help parents determine when to change the diaper. On the larger sizes, it's not really necessary. The larger a child gets, the more they pee – which leads to a very visibly swollen, misshapen diaper.
Overnight diapers are more absorbent than everyday diapers. They're designed to hold more liquid for a longer period of time, however, this can also depend on how much your child urinates and how long they sleep.
The smaller the nappy the less liquid it absorbs, so if you're regularly waking up to a saturated nappy or wet baby bed sheets, it might be time to go up a size.
Blowouts tend to happen at the back of the diaper where it is hard to create a seal. In many cases blowouts happen because of the wrong size diaper or diapers that aren't fully snug on the baby. It can be hard to ensure a good diaper fit when changing a wriggly baby!
As a rough guide, most babies fit into size 2 between the ages of 2 and 6 months, with some progressing into size 3 as early as 3 months old. In terms of how many size 2 nappies you need, you can expect your little one will go through approximately 8 nappies per day.
When you're securing your baby's nappy, if the sticky fastening tabs don't quite reach the centre of the waistband, the nappy is too small! For the perfect fit, the nappy should be snug but you should be able to comfortably fit two fingers under the waistband of the fastened nappy.
Size 1 nappies are designed for newborns and will fit most babies for the first few weeks of their lives, up to around 2 months.
Babies need frequent nappy changes. Babies have very delicate skin so their nappy needs to be changed as soon as they wet or poo themselves, otherwise their skin becomes sore and red. Changing your baby's nappy as soon as possible after they've done a wee or poo will help prevent nappy rash.
It should not require too much pulling or adjusting to secure the tabs. On the contrary, if the tabs overlap toward the center of the waist, you need to go down a size.
If your baby is at the smaller end of scale, you might opt for newborn size diapers, but if your baby is closing in on the upper end you might choose to start in size 1's. Many babies could really fit in either size (that's where the weight overlap comes in).
You Don't Have to Change Every Wet Diaper
Newborns poop lots, and you don't want to have your baby's cute little tushy sitting in that. But for pee diapers, you don't have to change the baby every time they go.
If your baby boy is peeing out the back of their diaper, the most likely cause is that his diaper is the wrong size. What is this? If your baby's diaper is too small, it will not be absorbent enough and their urine will leak either out the side, out the back, or up around their belly button.
Nappies need changing after every poo. You don't need to change your baby's nappy after every wee – rather, change the nappy just before or after a feed (but keep an eye out for nappy rash or skin irritation). There's no need to wake your baby at night for a nappy change.
The most common cause of leakage is fitting your baby with the wrong nappy size. So start by checking if the nappy size is right for your baby. Note also that the amount of pee increases as your baby grows. By the time your baby is 12 months old, the amount of pee discharged in a day will be twice that of a newborn.
Double up
If one nappy isn't enough, try two! Popping a second nappy over the top (ensuring it completely covers the first nappy) can offer the extra protection needed for a dry night.
Huggies absorbed an average of 84.5 mL of 5% salt water, while Pampers absorbed an average of 51.75 mL of 5% salt water (Table 2). We discovered that Huggies absorbed about 33 mL more than Pampers. This means that Huggies absorbed more simulated urine than Pampers.
To feel what a sufficiently wet diaper is like, pour 4-6 tablespoons (60-90 mL) of water into a clean diaper (if baby wets more often, then the amount of urine per diaper may be less). Diapers may be wetter in the morning, especially with older babies. Urine should be pale and mild smelling.
One way to find out whether a diaper is full, without having to actually feel inside of it, is to hold your hand over the front of your baby's diaper and jiggle it a teensy bit to see if it moves.
Days six and up: At this point, your newborn should have six to eight wet diapers a day, with some having as many as ten in a day. Some infants will need a diaper change after every feeding.