Infant Stooling Patterns and Type of Feeding
by Anne Eglash MD, IBCLC, FABM
Parents are usually taught that frequent stool and voiding patterns are reassuring signs of adequate breastmilk intake, in addition to an accurate naked weight demonstrating appropriate growth. Parents perceive that a decreased stool frequency might indicate a drop in breastmilk intake. There is little research on normal stooling patterns in breastfed vs formula fed infants, so we decided to focus today’s CQW on a rather small study that investigated this topic. A group of French researchers evaluated 84 infants for their stooling patterns over a 3-month period, with 48% exclusively breastfed, 37% partially breastfed, and 15% exclusively formula fed. They only compared the exclusively formula fed and exclusively breastfed infants for the frequency of stooling, and the rate of infrequent stooling, defined by not pooping for at least 3 days. The interval growth charts for all infants were considered acceptable..
- Exclusively breastfed infants have more frequent stools with more liquid than exclusively formula fed infants.
- By 8-12 weeks of age, stool frequency was not different between the exclusively breastfed and formula fed infants.
- 28% of exclusively breastfed infants had at least one 3-day interval of no stool in the first 3 months, vs 8% in exclusively formula fed infants.
- Most cases of infrequent stools (more than 3 days without stooling) occurred in the first 5 weeks of age.
- The average number of stools per day begins to decline significantly in breastfed infants at approximately 3 weeks of age.
- By 3 months of age, breastfed infants have on average approximately 2 stools a day.
See the Answer
Breastfed infants pass more stools and more liquid stools than formula fed infants and some have no bowel movements or infrequent stools for several days or weeks. We compared exclusively breastfed and exclusively formula fed infants for the first three months.
This study of 118 infants was carried out in the maternity ward of the Lille University Jeanne de Flandre Hospital, France, in 2015. The outcomes were the number and consistency of stools and the prevalence of infrequent stools.
At three months, 84 infants remained and we compared 40 who were exclusively breastfed and 13 who were exclusively formula fed. Daily stool frequency was significantly higher in the breastfed than formula fed infants during the first (4.9 1.7 vs. 2.3 1.6, p < 0.001) and second (3.2 1.6 vs. 1.6 1.5, p = 0.003) months. Stools were more liquid in the breastfed infants during the first three months. Infrequent stools occurred in 28% of breastfed and 8% of formula fed infants at least once. (p = 0.25).
Exclusively breastfed infants produced more stools than exclusively formula fed infants during the first two months and more liquid stools during the first three. Infrequent stools were 3.5 times more likely in the breastfed infants.
This study found that infrequent stools are most likely to occur after 5 weeks of age. The authors state in their discussion that there is no well-understood physiologic mechanism for infrequent stools in an infant who is growing well.
The findings in this study are useful clinically. First, we can inform families that it is normal for their breastfed babies to decrease frequency of stooling by 3-4 weeks. In my practice, some families call concerned about this, since it happens between the 2 week and 2 month visit.
Secondly, we can counsel families that after the first week of age, approximately ¼-1/3 of breastfed infants have episodes of not pooping for 3 days in a row.
Thirdly, we can determine with some certainty that very frequent stools, such as 8-10 per day is not typical after 3 months of age, and this may be a sign of something else, such as sensitivity to a substance in mom’s diet or a reaction to a medication, such as an antibiotic.