Re: 4 month old not gaining weight
Welcome to the forum!
If your baby is being fed on demand or at least 8-10 times in a 24 hour period, and is producing sufficient wet/poopy diapers, I don't think I see a problem. Yes, he's a lean baby but he has always been on the small side, and there's nothing wrong with being on the lower end of the weight-for-age charts. The charts aren't a test, where all the babies below the 50th percentile fail- there are healthy babies in all shapes and sizes, and statistically speaking there are just as many babies in the 10th percentile as there are in the 90th.
Your consumption/non-consumption of dairy won't make a difference to the quality/quantity of your milk. Women's bodies evolved to produce plenty of good milk even during food shortages. That's why most women gain weight during pregnancy- so they have energy reserves to fall back on just in case there's a famine. Your diet isn't going to do anything to your milk supply unless you are LITERALLY at the point where you are starving.
It's very normal for breastfed babies to drop percentiles as they get into the middle of their first year. Highly active babies often "lean out" somewhat earlier than their more sedentary peers. My kids both dropped percentiles between 2 and 4 months, going from around the 95-100th percentiles to around the 85-90th. Of course, no-one ever frets about the fat babies! It makes me a little... suspicious, I guess, when you say that your doc says she "sees this a lot in this age range". Does that mean that she's unaware of the normal changes in the rate of weight gain exhibited by breastfed babies, and is more comfortable with the escalating rate of weight gain seen in formula-fed babies?
Basically, I think that if your baby is happy, healthy, and continuing to gain weight at his own pace, there's no need to worry. You might want to find a different pediatrician, though.
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