Breast feeding and serum bilirubin values during the first 4 days of life

Midwifery management of breastfeeding: using the evidence

Strong evidence supports breastfeeding as the appropriate health choice for both mothers and infants. However, the mechanics of breastfeeding are frequently less well understood. This review of both the research and clinical evidence regarding appropriate breastfeeding management is designed to aid the midwife and other health care professionals in providing care and teaching, which will optimize maternal and infant health.

Is breastfeeding really favoring early neonatal jaundice?

OBJECTIVE

The purpose of this study was to evaluate the development of significant hyperbilirubinemia in a large unselected newborn population in a metropolitan area with particular attention to the relationship between type of feeding and incidence of neonatal jaundice in the first week of life.

STUDY DESIGN

A population of 2174 infants with gestational age >/=37 weeks was prospectively investigated during the first days of life. Total serum bilirubin determinations were performed on infants with jaundice. The following variables were studied: type of feeding, method of delivery, weight loss after birth in relationship to the type of feeding, and maternal and neonatal risk factors for jaundice. Statistical analyses were performed using the z test for parametric variables and the t test for nonparametric variables. In addition, the multiple logistic regression allows for the estimation of the role of the individual characteristics in the development of hyperbilirubinemia. Data concerning serum bilirubin peak distribution in jaundiced newborns were analyzed using a single and a double Gaussian best fit at least squares. The t test was performed to compare 2 values (high and low) of the serum bilirubin peak in breastfed and supplementary-fed infants with those in bottle-fed infants.

RESULTS

The maximal serum bilirubin concentration exceeded 12.9 mg/dL (221 micromol/L) in 112 infants (5.1%). The study demonstrated a statistically significant positive correlation between patients with a total serum bilirubin concentration >12.9 mg/dL (221 micromol/L) and supplementary feeding; oppositely, breastfed neonates did not present a higher frequency of significant hyperbilirubinemia in the first days of life. However, best Gaussian fitting of our data suggests that a small subpopulation of breastfed infants have a higher serum bilirubin peak than do bottle-fed infants. Newborns with significant hyperbilirubinemia underwent a greater weight loss after birth compared with the overall studied population, and infants given mixed feeding lost more weight than breastfed and formula-fed newborns, indicating that formula has been administered in neonates who had a weight loss beyond a predetermined percentage of birth weight. Significant hyperbilirubinemia was also strongly associated with delivery by vacuum extractor, some perinatal complications (cephalohematoma, positive Coombs' test, and blood group systems of A, AB, B, and O [ABO] incompatibility) and Asian origin. Multiple logistic regression analysis shows that supplementary feeding, weight loss percentage, ABO incompatibility, and vacuum extraction significantly increase the risk of jaundice, while only cesarean section decreases the risk.

CONCLUSION

The present study confirms the important role of fasting in the pathogenesis of neonatal hyperbilirubinemia, although breastfeeding per se does not seem related to the increased frequency of neonatal jaundice but to the higher bilirubin level in a very small subpopulation of infants with jaundice. In fact, in the breastfed infants, there is a small subpopulation with higher serum bilirubin levels. These infants, when starved and/or dehydrated, could probably be at high risk of bilirubin encephalopathy.

Differences in transcutaneous bilirubin readings in Japanese term infants according to feeding method

BACKGROUND

Controversy has existed for many years over whether infant feeding methods are related to serum bilirubin concentrations during the first few days of life. Differences in initial jaundice patterns according to the feeding method until 72 h after birth have not been elucidated hitherto. The difference may become clear in Japanese neonates because jaundice shows a much higher peak bilirubin concentration and a later peak in Japanese neonates than in Caucasian neonates.

METHODS

In the present study, we investigated variations in the transcutaneous bilirubin reading (TcB) obtained within 72 h after birth among 177 breast-fed and 494 formula-fed healthy Japanese term neonates.

RESULTS

There was no difference between TcB in formula-fed and breast-fed infants until the first 30 h, after which time the rate of increase in TcB was lower in formula-fed infants. Among breast-fed neonates, a good linear regression between time after birth and TcB was maintained. Similarly, weight losses in breast-fed infants at 24-48 h and 48-72 h after birth were greater than those in formula-fed infants.

CONCLUSIONS

The jaundice pattern in Japanese neonates from 30 to 72 h after birth according to the feeding method was different from that in Caucasian neonates.

Relationships between baby feeding types and patterns, gut transit time of meconium and the incidence of neonatal jaundice

The incidence of neonatal jaundice is reported to have increased in relation to breast feeding and various factors are thought to contribute to this either singularly or in concert. In a group of 150 full-term healthy babies, feeding types and gut transit time of meconium were examined. The findings demonstrated significant differences between feeding types and time taken to evacuate total meconium (p < 0.0001), weight loss/gain patterns (p < 0.0005) and the incidence of moderately severe jaundice (p < 0.01) during the early neonatal period. Baby feeding types were clearly defined in the study and a stool colour comparator was used to facilitate identification and classification of all stool colour transition from meconium through to yellow. Maximum weight loss was found to occur on the second day after delivery and in many instances the lost weight was regained by the baby on the fifth day. Exceptions to this were babies who fed ineffectively or inadequately. These outcomes suggest that the assistance and advice given to mothers and babies, by midwives and others, to achieve effective feeding practices in the days following birth is of paramount importance to the baby's immediate wellbeing.

Beta glucuronidase and hyperbilirubinaemia in breast fed infants of diabetic mothers

A prospective study was performed comparing bilirubin concentrations in 10 breast fed term infants of diabetic mothers (IDM) to those of 10 breast fed normal term infants. The beta-glucuronidase concentrations in serum and breast milk were assayed in the respective mothers. Significantly higher bilirubin concentrations were noted in the IDM group. Serum and breast milk beta-glucuronidase concentrations were significantly higher in diabetic mothers as compared with those of non-diabetic mothers. We suggest that the high concentration of beta-glucuronidase in breast milk of diabetic mothers is an additional important cause leading to hyperbilirubinaemia in their breast fed infants.

Breast feeding practices and severe hyperbilirubinaemia

This study establishes the association between early onset severe hyperbilirubinaemia (serum bilirubin (SBR) level greater than or equal to 272 mumol/L) with no assigned cause and breast feeding. The rates of breast feeding at hospital discharge increased from 46.4 to 75.4% in non-insured (public) women and 58.6 to 89.2% in insured (private) women between 1975 and 1987, and were accompanied by an increase in severe hyperbilirubinaemia from 1.6 to 3.1% in public and 0.9 to 3.6% in private babies. The case control study involved 125 term breast feeding infants born between 1 July 1985 and 1 July 1986 with severe hyperbilirubinaemia (SBR level 272 mumol/L) with no assigned cause who were compared with 125 matched controls who had peak SBR levels less than or equal to 272 mumol/L. Severe hyperbilirubinaemia was associated with primiparous and non-Caucasian mothers, non-smoking and oxytocin usage. Univariate analysis of feeding practice variables revealed that less frequent breast feeds, greater weight loss and less frequent stools over the first 3 days related to severe hyperbilirubinaemia (P less than 0.05). Multivariate analysis of the eight significant univariate factors revealed that maternal non-smoking, less frequent breast feeding, less frequent stooling and excessive infant weight loss were the best predictors of severe hyperbilirubinaemia. With the wide promotion of breast feeding, the contribution of individual feeding practices to severe hyperbilirubinaemia demands ongoing analysis and review.

Breastfeeding and breast milk jaundice

Two Types of jaundice associated with breast-feeding are recognized. The first type is early onset breastfeeding jaundice which may result from caloric deprivation and/or insufficient frequency of feeding. This type of jaundice can be prevented or treated by encouraging mothers to nurse as frequently as possible, particularly if the bilirubin level is rising. The second type is later onset, prolonged jaundice, known as the breast milk jaundice syndrome which is associated with one or more abnormalities in the maternal milk itself. Breast milk jaundice syndrome generally needs no therapy if serum bilirubin concentrations remain below 270 mumol/l in healthy full-term infants. When the serum bilirubin concentration is above 270 mumol/l and rising, temporary interruption of breastfeeding may be indicated.

Transcutaneous bilirubinometry in normal Japanese infants

We performed TcB readings in healthy full-term breast-fed Japanese infants from birth to seven days, and attempted to establish the normal range. TcB readings from Japanese infants were significantly higher over a longer period compared with Caucasian infants. The age of peak TcB readings in Japanese newborn infants was day 6, significantly later than that of Caucasian infants, day 3-4. We also attempted to estimate the total serum bilirubin concentrations using regression line relating TcB readings to serum bilirubin concentrations. Our study demonstrated that estimated total serum bilirubin concentration from forehead TcB readings was 0.56 +/- 0.35 mg/dl at birth, thereafter increasing to 6.8 +/- 0.5 mg/dl on day 1 and reaching a maximum of 12.6 +/- 2.5 mg/dl on day 6. These values and pattern in Japanese neonatal jaundice were significantly different from those of Caucasian children, but were similar to values and patterns from American Indians, Alaskan Eskimo, and other Asian full-term newborn infants. Thus TcB measurement may be useful for observation of the course of neonatal jaundice.

Breast milk jaundice in preterm infants

A retrospective study was performed comparing bilirubin levels in 40 preterm newborns with uncomplicated courses fed a combination of premature breast milk and formula to those of 60 comparable preterm newborns fed formula only. A significantly higher bilirubin level was noted in the group fed the combined diet on the 6th day of life and on the day of discharge. Seventy-six and seven tenths percent of the preterm infants fed breast milk and formula met the criteria for phototherapy, whereas only 45 percent were treated in the group fed formula alone. Our findings indicate that premature breast milk might cause early and late increase in bilirubin levels in healthy preterm newborns.

Perinatal events and neonatal morbidity: an analysis of 5380 cases

The associations between perinatal events and neonatal morbidity were examined in a regional population of 5 380 newborns weighing 500 g or more. Perinatal mortality was 6.9%, and neonatal mortality was 3.0%. The low birth weight (less than 2500 g) rate was 3.8%. The incidence of prematurity (gestational age less than 37 weeks) was 6.6%. Respiratory distress syndrome was found in 0.9%, nonhaemolytic hyperbilirubinaemia in 16.5%, hypoglycaemia in 0.5%, septic infection in 0.8%, asphyxia in 4.0%, intracerebral haemorrhage in 0.3%, and cerebral symptoms in 0.7%. Maternal toxaemia, multiple pregnancy and maternal short stature were associated with spontaneous prematurity and a birthweight below the 10th percentile. Prematurity was associated with respiratory distress syndrome, hyperbilirubinaemia, hypoglycaemia, infection, low Apgar scores, asphyxia and intracerebral haemorrhage. Placental complications were associated with spontaneous prematurity, low Apgar scores and asphyxia. Premature rupture of the membranes was associated with spontaneous prematurity, infection, low Apgar scores and asphyxia.

Weight loss and body temperature changes in breast-fed and bottle-fed neonates

Among 1138 newborns in a Level II nursery, breast-fed and formula-fed infants were comparable in terms of sex, mode of delivery, gestational age, birth weight, and birth temperature. Breast-fed neonates subsequently lost more weight and a greater percentage of their birth weight (mean, 7.4% vs. 4.9%) than did formula-fed infants. Loss of more than 10 percent of birth weight was associated with short gestation and low birth weight and with breast feeding. Birth weight loss of greater than or equal to 3 percent was associated with a risk of fever (greater than or equal to 37.5 degrees C) among breast-fed and formula-fed infants, but there was no gradient of increasing risk of fever with increasing percentage weight loss beyond 3 percent. After weight loss and other significant variables were adjusted for in a multivariate analysis, breast feeding was not independently predictive of fever. Although breast feeding may be associated with weight loss, it is not prudent to assume that this is the cause of fever in a breast-fed neonate.

Neonatal jaundice and fatty acid composition of the maternal diet

The role of serum fatty acid composition in neonatal jaundice was studied by comparing the incidence of jaundice among 332 newborn infants receiving breast milk from mothers on a diet with either a low (0.1, n = 145) or a high (1.5, n = 187) polyunsaturated to saturated fatty acid (P/S) ratio. The diet was started immediately after delivery. The composition of fatty acids in the breast milk and sera of the mothers and in the sera of the newborns was evaluated from a random sample of 15 mother-newborn pairs on the control diet (low P/S ratio) and 19 pairs on the experimental diet. Five days after delivery the relative amounts of fatty acids, especially that of linoleate, in the sera of the mothers differed significantly depending on the diet. Differences were also observed in breast milk samples taken three, four or five days after delivery and in the sera of the newborns sampled at the age of four or five days. Nine of the 145 newborn infants (6.2%) in the control group had to be treated with light therapy compared with 12 out of 187 (6.4%) of the newborn infants in the experimental group (high P/S ratio). Serum bilirubin concentrations were 142.5 mumol/l (SD 65.8) and 140.7 mumol/l (SD 73.5) in the experimental and control groups, respectively, at the age of five days. It appears that the changes in the composition of serum fatty acids reached in this study had no effect on the neonatal jaundice.

Fecal bilirubin excretion and serum bilirubin concentrations in breast-fed and bottle-fed infants

To assess the rate of excretion of bilirubin in the stools and its effects on serum bilirubin concentrations, we studied 24 breast-fed and 13 bottle-fed infants during the first 3 days after birth. Bottle-fed infants passed significantly more stool (3-day totals, 82 vs 58 gm, P less than 0.001), excreted more bilirubin (3-day totals, 23.8 vs 15.7 mg, P less than 0.05), and had lower serum bilirubin values (day 3, 6.8 vs 9.5 mg/dl, P less than 0.02). Among the breast-fed infants, greater stool output was associated with greater fecal bilirubin excretion (r = 0.56, P less than 0.05) and lower serum bilirubin concentrations (r = 0.66, P less than 0.001). Our data suggest that hyperbilirubinemia in breast-fed infants may be related to a delay in bilirubin clearance resulting from low stool output.

Incidence of hyperbilirubinemia in breast- vs. formula-fed infants

A retrospective study of 233 consecutively born full-term infants was performed to determine the effect of several variables on the development of hyperbilirubinemia. Thirty-five (15%) of the infants developed peak bilirubin levels greater than 12 mg/dl in the first week of life. Step-wise multiple regression analysis revealed that breast-feeding was the most predictive of a group of eight variables for the development of hyperbilirubinemia greater than 12 mg/dl. The correlation between type of feeding and hyperbilirubinemia was significant (p less than 0.02). None of the other factors evaluated was significantly associated with hyperbilirubinemia. Breast-fed infants also were found to have a significantly higher incidence of hyperbilirubinemia greater than 15 mg/dl; 12 of 101 (12%) infants compared with 2 of 117 (2%) formula-fed infants (p less than 0.002). This group of infants accounted for the increased incidence of hyperbilirubinemia greater than 12 mg/dl in breast-fed infants. There was no significant correlation between weight loss and development of hyperbilirubinemia in the breast-fed infants.

Effects of water supplementation on physiological jaundice in breast-fed babies

The effect of water supplementation in normal, term, breast-fed babies with physiological jaundice was studied. Water supplementation was given to 120 babies and 55 received no extra fluids. There was no significant difference between the two groups when peak serum bilirubin levels and incidence of phototherapy were compared.

Promotion of breast feeding: effect on neonates of change of feeding routine at a maternity unit

The effect on the health of neonates of a change in neonatal routine care, including general rooming-in, breast feeding on demand and avoidance of supplementary bottle feeding was studied in conjunction to a breast feeding campaign at a maternity unit. There was an accentuated weight loss in the neonatal period during ad libitum breast feeding. The mean serum bilirubin of clinically jaundiced infants was slightly higher on a 4-hourly feeding schedule with supplementary bottles than on the new regimen. There was a similar high (32-33%) incidence of bilirubin levels greater than 205 mumol/l (12 mg/100 ml) in both groups. The incidence of spontaneous hypoglycaemia did not differ in the two groups. The new feeding regimen was thus considered safe. Infants at risk for hypoglycaemia were given supplementary bottles and were excluded from the study.