Unfortunately, babies don't come with manuals. After my first baby was born I was told to feed her "on demand" and count her diapers. It all sounded pretty straightforward, until I was up all night nursing a crying baby. Later, I realized just how hard it can be to see a problem that is literally right in front of your face. I also learned that after their first few weeks, there are actually different red flags your baby isn't eating enough that you absolutely shouldn't ignore.
No matter how you feed your baby, it's natural to want to make sure they are getting enough to grow and thrive. Fortunately, there are some red flags that can help you identify a problem early and avoid long-term complications. According to the American Academy of Pediatrics (AAP), while it's normal for babies to lose up to 7 percent of their birth weight in their first couple of days of life, they usually regain their birth weight within their first week. After that they should gain 4 to 7 ounces per week. If not, it can be a sign of a problem.
Unfortunately, other red flags that your baby isn't eating enough are more subtle and might be a little harder to measure, especially for breastfeeding moms. According to Mayo Clinic, if your baby seems fussy after eating or seems like they are eating around the clock, they might still be hungry or not getting enough to eat. Also, your baby shouldn't be lethargic or difficult to wake, and should be alert and active at various times throughout the day. Fortunately, according to Jody Segrave-Daly, RN, MS, an International Board Certified Lactation Consultant (IBCLC) and NICU nurse, you can always take your baby in for a weight check if you think something is wrong or to make sure they are eating well.
The bottom line: if you have concerns about your baby's weight gain or how much they are eating, you should consult your doctor as soon as you can. Chances are, you can supplement and/or take steps to increase your supply, and if getting enough to eat is not causing their red flags, you can figure out if something else is going on.