Exclusive breastfeeding and jaundice

Article written by Dr Susan Tawia, Manager, Breastfeeding Information and Research team, for the May 2015 health professional member eNewsletter.

Jaundice in newborns is normal, particularly so in exclusively-breastfed infants. Disturbingly, in a very small number of babies, jaundice can progress to a point where it becomes a threat to the newborn. So, when should health professionals be concerned and what can be done to ensure appropriate bilirubin levels in exclusively breastfed infants?

Jaundice is the build-up of bilirubin (hyperbilirubinaemia) that is produced when red blood cells are broken down. Jaundice occurs on a continuum ranging from the normal, physiological jaundice seen in newborns to acute and chronic bilirubin encephalopathy (kernicterus).

The Academy of Breastfeeding Medicine Clinical Protocol #22 (Academy of Breastfeeding Medicine, 2010) describes the biological basis for jaundice in the newborn:

  1. Physiological jaundice in the newborn
    All newborns have some elevation of serum unconjugated bilirubin due to: the breakdown of red blood cells; the decreased uptake and conjugation of bilirubin by the liver; and the increased reabsorption of bilirubin by the intestines.
  2. Breastmilk jaundice
    Breastfed babies commonly have jaundice that continues into the second and third weeks of life and longer (8 to 12 weeks of life). In well babies, this is not a pathological condition, but appears to be a continuation of physiological jaundice which first appears in week one.
  3. Starvation jaundice
    In newborns, a reduction in energy intake below the optimal intake for age leads to even greater increases in serum unconjugated bilirubin levels. There does not need to be ‘absolute’ starvation to see this effect. Starvation jaundice of the newborn occurs more often in the first week of life when breastfeeding is being established, but it can occur later. Starvation jaundice appears to be mediated through an even greater increase in the intestinal absorption of unconjugated bilirubin.
  4. Kernicterus or chronic bilirubin encephalopathy
    Kernicterus (chronic bilirubin encephalopathy) can occur when serum unconjugated bilirubin levels reach a point where bilirubin crosses the blood-brain barrier and enters the neurons of the basal ganglia and cerebellum. The pathological changes are permanent and include chronic neurological impairment, neurocognitive delay and motor dysfunction.

A journal paper was published very recently (Chen, Yeh, & Chen, 2015) which looked at the incidence of jaundice in exclusively-breastfed babies. The research was undertaken in a Baby Friendly Hospital where: breastfeeding was initiated in the delivery room; babies roomed-in with their mothers; and babies were breastfed on demand.

Babies were assessed for jaundice at outpatient follow-up (on average day 7) and the presence of jaundice was correlated with the breastfeeding frequency. At follow-up, exclusively-breastfed babies were divided into two groups, those that were fed less than 8 times a day and those that were fed 8 or more times a day. The difference in the incidence of jaundice between the two groups was marked and statistically significant — 25.4% of babies fed less than 8 times a day were jaundiced compared with just 5.7% of infants fed 8 or more times a day (Table 1).

Table 1. Number of cases of jaundice at follow-up, according to breastfeeding frequency.

Breastfeeding frequency Jaundice at follow-up (on average day 7)  
Yes No  
% % P value
<8 times /day 25.4 76.4 <0.05
≥8 times /day 5.7 94.3  

Source: Chen, Y. J., Yeh, T. F., & Chen, C. M. (2015).

In this study, babies breastfeeding less than eight times a day are only feeding 4-hourly and this appears to be contributing to their jaundice. There was no statistical difference in the body weights at follow-up between the two groups of babies, so it appears that those feeding <8 times a day were getting adequate nutrition. The difference between the two groups is the number of times that breastmilk is moving through the gut and it may be this frequency of exposure of the gut to breastmilk that is important.

A study by Gartner, Lee and Moscioni (1983) used a rat model to look at the effect of breastmilk and cows’ milk formula on the intestinal absorption of bilirubin. In the absence of milk, 25% of bilirubin was absorbed, but the addition of breastmilk or cows’ milk formula markedly reduced the intestinal absorption of bilirubin to 2%. The researchers concluded that:

The remarkable effectiveness of both cow milk and human milk in almost entirely preventing intestinal bilirubin absorption … is supported by observations in the newborn human that increased frequency of nursing is associated with significant decreases in severity of physiologic jaundice. This decrease may be the result of acceleration of transit time or of a specific effect of milk in preventing duodenal uptake of bilirubin through binding of bilirubin to one or more components of milk. (Gartner, Lee & Moscioni, 1983, p. 470)

The observations that increased breastfeeding frequency is associated with a decreased severity of physiological jaundice referred to by Gartner and his colleagues were published more than 30 years ago in 1982 by De Carvalho, Klaus and Merkatz. They were concerned that:

Recent studies suggest that the three- to four-hour feeding regimens followed in many maternity units for breast-feeding mothers may not be physiological and that human infants should be fed more frequently. (De Carvalho, Klaus & Merkatz, 1982, p. 737).

So they looked at the difference in bilirubin levels between babies who were breastfed less than 8 times a day and babies who were breastfed more than 8 times a day in the first 3 days of life. Sound familiar?

They found that the group of babies who breastfed more than 8 times a day had significantly lower serum bilirubin levels than those who fed less than 8 times a day — 111.15 µmol/L compared with 159.03 µmol/L  (p<0.01). There was no statistical difference in weight loss between the two groups of babies, so it appears that those feeding <8 times a day were getting adequate nutrition. The difference between the two groups is the number of times that breastmilk is moving through the gut and it may be this frequency of exposure of the gut to breastmilk that is important. De Carvalho and his colleagues concluded that breastfeeding policies at the time, which reduced or limited the number of feeds, may have been interfering with the normal bilirubin elimination processes of the newborn.

To ensure that exclusively-breastfed babies are protected from the risk of non-physiological jaundice, they should be fed very frequently, more than 8 times a day, especially in the early days. Skin-to-skin care, unrestricted access to the breast, frequent breastfeeding and feeding according to babies’ needs are key to safeguard the health of a newborn and reduce the risk of jaundice.



Academy of Breastfeeding Medicine (2010). ABM Clinical Protocol# 22: Guidelines for Management of Jaundice in the Breastfeeding Infant Equal to or Greater Than 35 Weeks’ Gestation. Breastfeeding Medicine, 5(2), 87–93.

Chen, Y. J., Yeh, T. F., & Chen, C. M. (2015). Effect of breastfeeding frequency on hyperbilirubinemia in breastfed term neonate. Pediatrics International.

De Carvalho, M., Klaus, M. H., & Merkatz, R. B. (1982). Frequency of breast-feeding and serum bilirubin concentration. American Journal of Diseases of Children, 136(8), 737–738.

Gartner, L. M., Lee, K. S., & Moscioni, A. D. (1983). Effect of milk feeding on intestinal bilirubin absorption in the rat. The Journal of Pediatrics, 103(3), 464–471.