Your Baby’s Height and Weight

Steady weight gain is a sign that feeding is going well and your baby is healthy. In the early days after birth, it is normal for a baby to lose some weight. Your baby will be weighed to make sure they regain their birth weight.

Four out of five healthy babies are at or above their birth weight by 14 days. If your baby loses a large amount of weight, your health visitor will talk to you about how feeding is going and will look at your baby’s health in general. After this, your baby will only be weighed during routine reviews unless there’s cause for concern. Your health visitor may ask you to bring your baby more often if they think they need more regular monitoring.

Generally, you don’t need to weigh your baby too often and no more than once a month up to six months of age, once every two months from six to 12 months of age, and once every three months over the age of one.

A baby’s length is measured by trained staff using appropriate equipment. By two years of age, your child’s height can be measured when they are standing up.

Understanding your child’s chart

Your child’s growth will be recorded on a centile chart. This allows you to see how their height and weight compare to other children of the same age. Boys and girls have different charts because boys are on average heavier and taller and their growth pattern is slightly different.

They represent the pattern of growth that healthy children should follow, whether they are breastfed or formula fed. They are suitable for children from all ethnic backgrounds.

Centile lines

The curves on the chart, or centile lines, show the range of weights and heights (or lengths) of most children. If your child’s height is on the 25th centile, for example, this means that if you lined up 100 children of the same age in order from the shortest to the tallest, your child would be number 25 and 75 children would be taller.

It is normal for a child’s weight or height to be anywhere within the centile lines on the chart.

The centile lines show roughly the pattern of growth expected in weight and length, but these do not usually follow one centile line exactly. Weight usually stays within one centile space (the space between two centile lines).

All babies are different and your baby’s growth chart won’t look exactly the same as another baby’s (even their brother’s or sister’s).


Usually, weight gain is quickest in the first six to nine months and gradually slows down as children move into the toddler years.

If your baby is ill, weight gain may slow down for a while. Toddlers may lose weight when they’re ill. When they recover, their weight will usually return to normal within two to three weeks. If your baby drops two or more centile spaces from their normal position, ask your health visitor to check them and measure their length.


Your child’s height after the age of two can give some indication of how tall they will be when they grow up. It’s normal for your child to be on different centiles for weight and height/length, but the two are usually similar.If there’s a big difference or if your nurse or doctor is concerned about your child’s weight, they will calculate their Body Mass Index (BMI) centile. will show if your child is overweight or underweight. If this is the case, talk to your health visitor about your child’s diet and physical activity levels. They can help you plan any changes needed.

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Maya Expert Team