Objective: The most common reason given for discontinuation of exclusive breastfeeding is perceived insufficient milk supply. Breastfed infants show more variation in feeding frequency than bottle-fed infants, and this may lead to a mother lacking confidence in her milk supply if the frequency of breastfeeding sessions does not match expectations based on bottle feeding. We aimed to assist clinicians in supporting breastfeeding mothers by providing evidence-based information on expected changes in breastfeeding patterns and milk intake during exclusive breastfeeding for 6 months. Subjects and Methods: Mothers and their healthy infants who were exclusively breastfeeding (total 24-hour milk intake within the normal range) were studied during two to five 24-hour periods between 1 and 6 months of lactation. Results: Between 1 and 3 months of lactation, the frequency of breastfeeding sessions decreased, whereas both the median and maximum breastmilk intakes during each breastfeeding session increased. These parameters remained constant between 3 and 6 months. The duration of each breastfeeding session decreased steadily from 1 to 6 months, but the total 24-hour milk intake remained constant. Conclusions: Breastfeeding becomes more efficient between 1 and 3 months of lactation, although milk intake remains constant. Clinicians can give mothers confidence that these changes in breastfeeding behavior do not indicate insufficient milk supply, but may be a result of the increase in the stomach capacity of the infants and are an expected outcome of a healthy, normal breastfeeding relationship.

Objective Mothers need reassurance that the breastfeeding behaviour of their babies is normal, but the range of normality and changes with stage of lactation have not been defined. Methods Forty-two mothers of exclusively breastfed babies test-weighed their babies before and after every breastfeeding session for a 24-h period in their own homes at 1, 2, 4 and 6 months after birth. A breastfeeding session consisted of a feed from one or both breasts depending on the baby’s appetite. Results There were 7.0 breastfeeding sessions a day (range 4–14), with fewest (6.4) at 2 months. Each breastfeeding session lasted 41 min (range 21–101 min) at 1 month decreasing to 28 min (range 11–54 min) at 6 months. The longest interval between breastfeeding sessions increased from 4 h 54 min (range 2 h 24 min–8 h 55 min) at 1 month to 6 h 52 min (range 3 h 29 min–10 h 30 min) at 6 months. The babies consumed 112 g at each breastfeeding session (range 58–227 g) with a maximum amount (136 g) at 2 months. The total milk production of the mothers was 821 g/24 h (range 464–1370 g/24 h) and did not change during the period of exclusive breastfeeding. Conclusions There was at least a three-fold variation between infants in breastfeeding frequency, duration of breastfeeding sessions, longest interval between breastfeeding sessions, and milk intake. Mothers can be reassured that all babies do not need to show the same breastfeeding behaviour. During the lactation period babies can be expected to become more efficient, but will not increase their milk intake. The authors receive research funding from Medela AG (Switzerland).

We have developed a computerized breast measurement system that can quantitate both long-term (lactation cycle) and short-term (between breastfeedings) changes in breast volume. The increase in breast volume during pregnancy was not related to milk production at one month of lactation, whereas milk production from one to six months of lactation remained constant and was not controlled directly by the suckling-evoked secretion of prolactin. From the measurement of circadian changes in breast volume, it was concluded that infants rarely emptied the breasts at a single breastfeeding and that short-term variation in the rate of synthesis during the day and between the left and right breasts was closely related to the degree of breast fullness. Furthermore, differences between women in the storage capacity of the breasts dictated their flexibility in frequency of breastfeeding. These observations are consistent with the autocrine (local) control of milk synthesis during established lactation in women.