Volume of Expressed Colostrum in the first 48 Hours Postpartum
by Anne Eglash MD, IBCLC, FABM
There are few studies that have evaluated the volume of colostrum produced in the first few days postpartum, before secretory activation (when the milk ‘comes in’) occurs. Most lactation consultants would likely say that there is wide variability between lactating individuals regarding colostrum volumes.
The publication for this week is an observational study of 105 mothers in Japan who were asked to manually express their colostrum for 10 minutes every 3 hours for 48 hours, with the goal of evaluating the change in colostrum volume during the first 48 hours. These mothers were unable to directly feed due to infant admission to the neonatal intensive care unit. The authors report that it is culturally acceptable in Japan to manually express milk in the initial postpartum phase with assistance and instruction from midwives.
Sixty-three women (60%) of the mothers began expression within 3 hours postpartum, and the frequency of hand expression ranged from 5-8 times in the first 24 hours, and 6-8 times between 24-48 hours postpartum. Midwives assisted mothers who had difficulty expressing their colostrum.
The total volume expressed in the first 24 hours ranged from 0.1-11.2 ml, and from 2.2-40ml between 24-48 hours postpartum. The lowest volume of colostrum occurred between 12-15 hours, and the volume stayed low until a sudden increase in volume at 30-33 hours postpartum. What else? See the question!
- In the first 30 hours postpartum, the multiparous mothers had significantly higher colostrum volumes than the primiparous women.
- The mothers who gave birth at gestational age 32-36 weeks had higher colostrum volumes as compared to those who gave birth at gestational age 22-31 weeks.
- Colostrum volume was higher among women who delivered vaginally as compared to those who delivered via cesarean.
- Colostrum volume increased earlier among mothers who began manual expression in the first 3 hours vs those who began at 3-6 hours postpartum.
See the Answer
Colostrum, the first form of human milk, is strongly encouraged for infants due to its benefits. During the early postpartum (PP) period, the secreted colostrum volume can be minimal, causing concerns among mothers about sufficient milk supply. Few studies have examined temporal changes in the colostrum. This study aimed to elucidate the trajectory of expressed colostrum volume in the first 48 hours after delivery.
Materials and Methods
This was a cross-sectional observational study performed at Kagawa National Children’s Hospital. One hundred five mothers who did not directly breastfeed in the first 48 hours after delivery were enrolled in the study. Well-trained midwives instructed the mothers on how to express human milk, and mothers started to express as soon as possible after delivery. Mothers were advised to express human milk every 3 hours, and the milk volume was measured.
Within 3 hours PP, 60% of mothers expressed milk, and the median frequency of expression was 14 (interquartile range, 11–16) times in the first 48 hours. At 0–3 and 3–6 hours PP, the volume of initially expressed milk was 0.4 (0.0–2.0) mL and 1.0 (0.0–6.0) mL, respectively. Subsequently, milk volume decreased. The volume remained low until 30 hours PP and increased dramatically; this phenomenon is termed secretory activation, which began later in primiparous women than in multiparous women.
The decline in expressed milk volume during the early PP period caused concern among mothers. Therefore, mothers should be informed of the PP trajectory of human milk volume.
The researchers found that multiparous mothers didn’t have higher colostrum volumes than primiparous mothers until after 30 hours, when the volume of colostrum greatly increased. At that point the rate of increase in milk volume was faster in multiparous mothers than in primiparous mothers.
Gestational age at birth and mode of delivery did not have an impact on colostrum volumes.
One important aspect to this study is the lack of adjustment for maternal BMI. There is increasing evidence that an elevated body mass index is associated with a delay in lactation, which would likely be associated with lower colostrum volumes.
The take-away from this study is that colostrum volumes are higher in the first 12 hours than in the next 18 hours. By 30 hours postpartum the volume of colostrum climbs exponentially.
This may explain why there may be more stools in the first 24 hours, followed by a slowing of stools after 24 hours until milk volume increases at 30 hours and beyond.