Baby weight by stages: growth and reference values
Manuel FernándezHow much weight should your baby gain every month?
During the first few months after your baby is born, one of the things that can worry you most is your baby's weight. It's the reason behind many online searches as well as visits to the paediatrician. That's why our midwives at Happymami have written this post for you, with everything you need to know about your baby's weight by stages.
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If you're a mum, you've probably asked yourself the question "how much should my baby weigh?" more than once, because your baby's weight by stages is a topic that comes up again and again. But as common as it is, in most cases your baby's weight progress is normal. We'd also like to tell you that giving an exact figure is very difficult, and that it should always be assessed jointly with a healthcare professional, taking into account other factors such as age, sex, feeding and genetics, among others. How do I know if my baby is getting enough milk?
Newborn under 10 days old
Before we start, and if your baby is less than 7 to 10 days old, you should know that during these days a weight loss of 10% is normal. What does this mean? First of all, that it is completely normal. As an example, a baby who weighed 3,300 grams at birth can lose weight and drop to 3,210 grams over these 10 days, and would still be normal.
Start designing your bottleIn the first month of life
The first month as a mum and dad is usually the acid test. I'd like to go into a little more detail, so I'd like to share with you a table from the World Health Organisation showing the normal weight values for girls and boys by week. In general, the approximate weight gains of babies are:
- 0-6 weeks: 20 g/day
- Under 4 months: 100-200 g/week
- 4-6 months: 80-150 g/week
- 6-12 months: 40-80 g/week
| Weeks of life | Boys | Girls |
|---|---|---|
| 0 | 2.5 – 4.3 kg | 2.4 – 4.2 kg |
| 1 | 2.6 – 4.5 kg | 2.5 – 4.4 kg |
| 2 | 2.8 – 4.9 kg | 2.7 – 4.6 kg |
| 3 | 3.1 – 5.2 kg | 2.9 – 5.0 kg |
| 4 | 3.4 – 5.6 kg | 3.1 – 5.3 kg |
What's more, if you are breastfeeding, everything is probably going well if the following happens: you feed between 8 and 12 times a day, your baby wets 4 to 5 nappies with urine a day and has several bowel movements a day. And your baby is content and settled after feeds.
From the second to the fourth month of life
At this stage, your baby probably has a more settled feeding pattern and your breastfeeding is well established. During these months, the weight gain is between 100 and 200 grams a week. This gain is a guide: your baby may gain more one week and less the next, but the figures will be around that range.
Start designing your bottleBetween the fifth and sixth month of life
By now, as a mum and dad, you know your baby well, and it's normal to feel more confident about motherhood. The rate of weight gain slows down compared with the previous values, dropping to 500-600 grams a month.
Babies over 6 months
It's time for the introduction of new foods, and the weight gain keeps slowing down, going from 350-400 grams a month at the beginning of the 6 month mark to a gain of 250 to 300 grams a month by the end of the first year of life.
Percentiles
To get an estimate of your baby's normal development, the WHO updated the percentiles in 2006. These are charts that show the normal growth of healthy babies. Within these charts there are 5 upward curves marked on a graph. Each curve corresponds to a percentile: 3, 15, 50, 85 and 97. They represent what is normal in terms of babies' weight and height. It's important to know that a baby on the 97th percentile is just as normal as one on the 15th. That's because, just like adults, we all have different body shapes even when we're healthy, determined genetically by our mother and our father.
Reasons to see the paediatrician
As we mentioned earlier, every baby is unique, and whether your baby's growth is optimal should be assessed by their paediatrician, with a comprehensive evaluation of each case. Although the AEPED gives us some recommendations on when to seek advice, and I quote verbatim:
- Prolonged weight loss lasting more than 4 days from birth, or failure to regain birth weight by 14 days of life.
- If the baby is very irritable, very alert or drowsy and unresponsive. (what your baby's crying means)
- Also if they fall asleep after only a few sucks at the breast.
- If the number of soiled nappies (urine and poo) decreases or orange crystals appear.
- If they latch on poorly, with the mouth very closed, far from the breast or sucking very fast. (Breastfeeding guide)
Conclusion on baby weight gain
A child's growth should be monitored by the paediatrician at the consultation once a month or whenever necessary. Weighing your baby more often at home or at the pharmacy can lead to mistakes in managing breastfeeding. You can complete this information with the Newborn Care Guide. We'd also like to remind you that if you need to use a bottle and you want it not to affect your breastfeeding, we have our Happymami, a bottle designed 100% by the mum for her baby. So that there is no difference between breastfeeding or feeding your baby from your Happymami. That way, your baby won't suffer from nipple confusion, protecting your breastfeeding.
