For first time readers who have arrived here, this post is part of a 12-part series as described in the A Baby Feeding Journey over 14 Months (a 12 Part Series), an overview of our daughter’s life told through data. We are going to look at baby diaper trends by month in data to see how much pooping and peeing changes over time.

Today’s post may be a secret favorite of mine, mostly because it was so fascinating to watch it unfold over time. As background, before our baby was born, I had never changed a single diaper in my life. My entire notion of diaper changing came from family and friends who had kids, and to be frank, mostly Hollywood. And it was Hollywood that made diaper (nappy) changing seem like it was one of hardest parts of baby rearing, and certainly emphasized the disgusting parts of it.

If you ask me, if all baby-rearing was as easy as diaper changing, then it would be pretty straightforward. And as any new or seasoned parent can tell you, it is not easy to raise a child. As for the “disgusting” part, yes, at times blowouts may happen (and your mileage may vary as to how often or problematic this is in your own baby’s case), but when it is your own baby’s pee and poop, you just don’t feel the “disgust” as you might with others, or even yourself. It’s just a job that needs to get done, for an otherwise helpless little being. Plus over time and with more practice, you almost become robotic-like in your efficiency in getting dirty diaper off, clean diaper on.

With all that said, this isn’t a diatribe about diaper changing. This is about the data behind it. And pee and poop are obviously direct outputs based on what your baby consumes (breast milk, whether direct from nursing or pumped, formula, solids, and any supplements/medications). It is also is a developmental journey depending on your child as to how their digestive system and microbiome evolves. Allergies can play a part in these inputs and outputs, as can illnesses.

The data below looks at pees and poop by month in the table, as well as with a 7-day moving average in the chart, combined with what the baby was consuming at the time so that you can see the effect.

Chart 1: Lifetime Diapers (7-day moving average)

Table 1: Monthly Totals of Diapers and Feeds

Table 2: Daily Averages of Diapers and Feeds

Chart 2: Poops & Solid Feeds (7-day moving average)

Chart 3: Pees & Liquid Feeds (7-day moving average)

Some Highlights

• Constipation Signs at the Beginning: Our baby seemed to strain when trying to poop at the beginning and went a day or two without pooping at all. Now at time, this could have been linked to the weak suck we discovered she had at her one-month checkup (we will discuss this more in our pumping journey in data) and not getting enough milk/food, and/or the fact she was more on the lower weight side. So perhaps she did not have as mature a digestive/bowel system, as suggested by our night nurse. Or maybe it was just our baby’s development path. It also could have been none of the above. Regardless, it wasn’t pleasant for us, watching her strain and feeling that her stomach was hard, so we (via our night nanny) knew there was some output that needed to come out, which had to be manually stimulated a couple of times. It is for this reason you will see “Prune juice” taken in small doses across the day in the early weeks in our chart. Prune juice was recommended for constipation by our pediatrician. Giving baby prune juice seemed to make the pooping easier, and perhaps even made her poop a little more if you look at the trends.
  
  
• You can see the evolution of liquid bottle feed amounts per poop, which peaked at 1.1L (1065 mls or 36 oz) of consumption per poop in month 5. By month 9, that was almost cut in half to 575 mls (19.4 oz) of consumption per poop, even though her overall daily food consumption had only dropped by 20% (887 mls / day in month 5, down to 723 mls / day in month 9).
  
  
• Breast Milk Makes You Poop Less? So you can see in month 1 (a 31-day month), despite the above, she pooped almost twice (1.9x) a day. Some of these were admittedly small. By months 4-5, this had dropped to less than once per day (0.8x).
  
  
• A couple of things you will see over this period is that we eliminated prune juice after a little over 2 months, and month 2 at 215 mls (7.3 oz) of prune juice consumption was her biggest month, but she pooped 32% less (1.3x per day) than month 1 when she only had 90 mls (3 oz). So based on this, we can’t say prune juice was the cause given she was already declining in pooping, despite having more prune juice.
  
  
• So this brings us to the topic of breast milk, which in month 1 was about 40.7% of her diet (potentially more if you read “Pumped Breast Milk vs. Formula in Data“), but by month 4, it made up 86.4% of her diet, and month 5 81.3% of her diet. During month 5, she also consumed (in raw amount) about 200 mls more breast milk than during month 4. Many sources say babies may tend to absorb more breast milk than they do formula, and thus expel more formula out via peeing and pooping. In our case it seems to be the more likely explanation, and may potentially be explained also by the type of formula she was consuming over this period, which we will discuss later.
  
  
• Solids make you poop more? Now to continue the pooping story from month 7, her frequency rose pretty dramatically from 1x a day to 2x per day at month 10. And it stayed at above 2x per day right through this data series to month 14. Month 12 (30-day month) and month 14 (31-day month) at 69x poops in the month were here biggest raw numbers, albeit month 12 at 2.3x per day was most frequent. You can see over this same period her solid consumption grew dramatically from less than once per day (0.9x) in month 7 to almost three times per day (2.8x) in month 11, and consequently her breast milk consumption reduced a lot, which we talk about in A 1+ Year Breast Pumping Journey. By the end of month 11, solids were clearly becoming the vast majority of her diet.
  
  
• Baby’s poops also became a lot stinkier as she ate more solids and drank less breast milk. Just FYI and we will talk about what those solids were in Year 1 Solid Feeding & Introducing New Foods to Your Baby in Data, which probably further emphasized it.
  
  
• In the middle of month 9, we took our baby on her first plane trip across the continental U.S. from New York to California. As we were getting in the routine and ramping of solid feeding during this time, there was a slight disruption to the ideal routine for about a week, but largely the baby handled it well, including while in-flight. However, this is why you see a slight drop in solids per day (1.7x vs. month 8 at 2x), and potentially why the dramatic jump in poops happened after month 9. We also took her on more extensive travel in month 12 and 13, and will discuss that more in the Solids post and the baby and travel post.
  
  
• We haven’t talked much about peeing, and honestly that is because that became as much a function of personal caregiver style and routine, than it really did about how much she actually peed. You will see drops in months 4 and 5, and then again in months 12 and 13, from the trends of the months before. They largely reflect the periods when we were mostly/solely in charge of diaper changing as parents, and we did it slightly less often than when we had paid caregivers also involved significantly in child care. Generally speaking, this was 5-6x per day throughout, but from the chart, you can see quite a bit of daily volatility.
  
  (As we noted in the A Baby Feeding Journey over 14 Months (a 12 Part Series) overview, this 14-month data series starts at Day 6 of our baby’s life, so it does not include the meconium/first-poop, or those initial pees the baby had in first 5 days).