Weight gain dropped in 4 month

[vgahdmi123]

Baby boy born in July, very happy, smiling, making sounds, met all milestones even for 6 months now. He doubled his weight in 90 days reaching 6 Kg from 3 Kg after birth. In average he was putting 1 Kg per month.

However, after entering 4 month his weight gain dropped significantly, he is now maybe getting 10-15 grams per day which will be 400 grams per month. I have to mention that he is tall baby compared to others (90 percentile), and his weight was always 50 percentile but now seems dropping a bit. He is only breastfeed. We were thinking to include formula, but he does not like it and making weird faces when we give it to him.

Doctor put him now on weekly weight monitoring, he says he should be getting 750 grams until 6 months old so not sure should I be concerned, what is your experience?

My daughter only gained 200g between 7 and 13 months. She dropped just over 1 percentile but her paediatrician, dietitian and HV weren't worried. Our HV said it's quite common on weight to stagnate a bit between 6 and 12 months as there can be a mismatch in appetite and activity. My daughter didn't engage with weaning until 13 months when she started to gain weight. My daughter is now 3 and has bounced between two percentile lines several times she will gain really well reach the 50th percentile stay there for 3-6months the next 6 months she won't gain much at all and drop to the 25th percentile stay there for a while then move up again.

As long as she only drops 1-2 percentiles and doesn't actively lose weight our medical team isn't worried. I find her red book embarrassing though just by how many weight checks we have had! My daughter started on the 9th percentile and has issues with allergies and reflux.

For a 50th percentile boy to go from 18 weeks to 22 weeks they need to gain 500g to stay on the 50th percentile so the 400g expected gain would only put him slightly under.
If he was 6kg at 3 months that puts him in between the 25th and 50th which is the same time range as currently. If they are normally around 50th percentile and are anywhere above the 25th percentile that would be usually counted as good.

The weight per day does change as they get bigger you can see how the lines flatten in the book. I would focus on where he is on the charts rather than exact weights

but what are usually causes for sudden weight growth speed drop? I don't think he is sick because he is very active and happy, he is breastfeeding 9-12 times per day, having 6-9 wet diapers and pooping 2-3 times per day.

Being very active will probably be the reason!
Babies don't grow by the book some times they do sometimes the grow quicker and other times slower

It's normal to move around percentiles a bit so if you are on the 50th percentile you might go up a bit and be closer to the 75th percentile or drop closer to the 25th it's normal fluctuations in weight.

If they were to drop from the 50th percentile to the 9th or below that would be more concerning. I would be focusing on where they are on the chart rather than the day by day weight gain.

An imbalance between the amount eaten and movement can cause a drop in weight. This was behind my daughters she was just so active and on the go all of the time. Even though she breastfeed the same amount as before she had gone from not moving to moving and that is a big drain of calories.

Allergies, reflux and tongue tie would be the biggest causes of slow weight gain. My sister had slow weight gain due to reflux, she projectile vomited every bottle. She was 3kg a birth (25th percentile) and by 10 weeks she was only 3.5kg and below the 0.4th percentile. She didn't reach the 0.4th percentile until she was 1 and she stayed there until she was nearly 2 when she jumped up to the 50th percentile. Based on similarities with my daughter I think she probably had a dairy allergy too. She had random sickness throughout her life which stopped when she went vegan in her late 30s so possible still had poor tolerance of dairy.

It doesn't sound like his weight gain has slowed to the degree of it causing him to drop on the charts. It's is good that they are keeping an eye on him but try not to obsess about all of the numbers it's exhausting (I know!)