One of the ways to know if a baby is feeding properly is by observing its weight, which is recommended to be done every week during the first months of life. However, you should not be obsessed with weight since they might put on more weight in a week than another.  

The weight of a newborn ranges between 3 and 4 kilos. In the first two days it is normal for them to lose up to 10of their weight due to the expel of meconium and the start of breastfeeding. From then on, the baby should gain 20g to 30g every day to reach the same weight of the childbirth in around 10 daysWhen two weeks old, the baby should weight more than at birth. 

Babies normally gain between 120g and 200g per week in their first months of life. Thus, from the first to the third month, it usually fattens between 600g and 800g per month. This growth can slow down a bit between the fourth and sixth month. Between 6 and 12 months, it is usual for them to gain less weight per week, about 125g, until they reach only 50g of weight growth per month. 

Always keep in mind that each baby is different, and some are more gluttonous than others, which can make them gain more or less weight per week. It should also be borne in mind that fattening is not mathematical. One can gain 90g this week and, the next, 180g. Therefore, it is recommended not to obsess about weight or weigh your baby more than once a week.  

Many newborns go through a period of rapid growth when they are about 10 days old. Other two peaks happen around 3 and 6 weeks oldSo you may have weighed your baby just before that peak of growth and then will you be misled to think it has gained little weight, when it is not true.  

You should always observe the paediatrician’s reviews and be aware of other signs that the baby eats enough, such as regular urinating, rounding of the body shapes, etc. 

Bear in mind that breastfed children tend to gain weight slower and take more feedings than bottle-fed infants. The nursing moment is caloric-consuming until the baby learns to do it well and the birth weight does not determine its later growth. 

In short, it is important to control weight, but you should not obsess about it, what is really essential is that the baby feeds properly, is happy, grows and develops favourably, not weighing 100 grams more or less.