Healthy Breast-fed Infants Research Articles

Hyperbilirubinaemia in healthy breastfed infants

Hyperbilirubinaemia in normal full-term breastfed infants has previously been consider pathologic in origin. Recent evidence shows that breastfeeding jaundice and breastmilk jaundice are aetiologically different but possibly overlapping syndromes and an exaggeration of normal physiologic mechanisms. Infants with breastfeeding jaundice may be more vulnerable to the later onset breastmilk jaundice. Recent studies show that kernicterus or neurophysiological defects rarely occur in normal breastfed infants, and call for a review of management protocols regarding the use of diagnostic tests and phototherapy. Midwives need to discern more accurately the need for diagnostic tests and to challenge outdated management protocols that aim to ‘treat’ healthy infants with hyperbilirubina.

Thirst and vasopressin secretion counteract dehydration in newborn infants

Our goal was to study the water balance in healthy breast-fed infants (n = 139) during their first 5 days, by cross-sectional measurements of body weight, serum sodium, serum osmolality, and hematocrit. We also investigated infants' capacity to conserve body water by increased secretion of vasopressin, the main antidiuretic hormone in human beings. The maximal body weight reduction was 5.7% +/- 1.7% (mean +/- SD) of birth weight and most infants started to gain weight when they were 3 days old. The serum sodium level at 16 +/- 4 hours (on day of birth) was 142 mmol/L; the level increased after 1 day (p < 0.01) and remained constantly high for the following 2 days (p < 0.05). The serum osmolality was increased at 1 day (p < 0.01) and 2 days (p < 0.05) compared with the value on the day of birth (296 mOsm/kg). The plasma vasopressin level was constant up to 24 hours (1 day), but decreased during the next 2 days (p < 0.01). Infants with body weight reduction exceeding 10% (n = 15) had a further elevation of the serum sodium level (p < 0.0001) and serum osmolality (p < 0.0001), and the plasma vasopressin level was twofold higher (p < 0.0001) compared with corresponding levels in infants with less weight reduction. These infants also had a reduced interval between two subsequent feedings (p < 0.001). The hematocrit remained unchanged irrespective of the degree of weight reduction. When the reduction of body weight exceeds 10%, the newborn infant releases vasopressin in response to fluid hypertonicity. This state also affects feeding behavior, perhaps as an expression of thirst. It is likely that hormone release is also stimulated in parallel with a weight reduction of less than 10%, because it is also accompanied by a hyperosmotic state.

Low Vitamin B6 Status Associated with Slow Growth in Healthy Breast-Fed Infants

To evaluate the effect of vitamin B6 status on infant growth, we studied longitudinally anthropometry and the erythrocyte parameters that reflect long-term vitamin B6 status [erythrocyte pyridoxal 5'-phosphate concentration (EPLP), erythrocyte aspartate transaminase basal activity (EAST0), and its activation co-efficient (alpha EAST)] in 44 infants. The infants were exclusively breast-fed for 6 mo, given additional solids according a uniform schedule from 6-9 mo, and formula after 9 mo, if needed. In seven of these infants, a low vitamin B6 status (EPLP < 10th, and EAST0 > 10th or alpha EAST > 90th percentile for these values in reference infants) was observed between 4 and 6 mo of age. These seven infants showed slower length velocity (0.30 +/- 0.05 versus 0.40 +/- 0.02 mm/d, p < or = 0.02) and deeper fall in length-for-age (-0.69 +/- 0.20 versus -0.25 +/- 0.07 SD score, p < or = 0.03) from 6 to 9 mo of age than the similarly fed infants with higher vitamin B6 status. Preceding vitamin B6 status remained a significant explanatory factor for length velocity and change in length-for-age in addition to preceding and concomitant weight velocity, when sex, birth size, preceding length gain, and mid-parent height were taken into account. Change in weight-for-age alone explained 16% and 18% and, together with vitamin B6 status, 23 and 27% of the variation in length velocity and in change in length-for-age, respectively. Thus, in healthy breast-fed infants, according to our results, low vitamin B6 status is associated with reversibly reduced gain in length.

Hospital Readmission Due to Neonatal Hyperbilirubinemia

Severe neonatal hyperbilirubinemia can occur without apparent reason in term healthy breast-fed infants and some develop kernicterus. The aim of our study was to assess the incidence of severe hyperbilirubinemia in term healthy newborns discharged from the hospital. From January 1 through December 31, 1994, 6705 infants were delivered at Bikur-Cholim and Misgav-Ladach Community Hospitals. All 1448 newborns discharged with a serum bilirubin level > 10.0 mg/dL were instructed to return to the hospital within 3 days for follow-up, as well as bilirubin determination. Twenty-one newborns with a bilirubin level > 18.0 mg/dL were identified and readmitted at mean +/- standard deviation (SD) 5.5 +/- 1.8 (range, 5 to 10 days of life). This represents 1.7% of the 1220 infants who returned for follow-up examination. Mean +/- SD serum bilirubin levels at readmission were 19.6 +/- 2.5 mg/dL. All but one of the infants were breast-fed. No cases of ABO incompatibility were found and two newborns were glucose-6-phosphate dehydrogenase (G6PD)-deficient. Sepsis work-up and direct Coomb's tests were negative in all cases. None had hemolysis or were found to have any cause for hyperbilirubinemia other than breast-feeding. Phototherapy was provided in all but two cases, and an exchange transfusion was performed in one case. Three additional infants, with bilirubin levels < 10 mg/dL at discharge, were readmitted due to hyperbilirubinemia. One was diagnosed with neonatal hepatitis. We conclude that, based on our study population, 0.36% of term infants may subsequently develop severe neonatal hyperbilirubinemia in the first postnatal week.(ABSTRACT TRUNCATED AT 250 WORDS)

A study of the iron requirement in infants, using changes in total body iron determined by hemoglobin, serum ferritin and bodyweight

The amount of iron absorption in healthy breast-fed infants was estimated in order to assess the iron requirement. This was carried out by monitoring changes in total body iron (TBI). Hemoglobin and serum ferritin were measured to calculate hemoglobin iron, body storage iron and TBI at the ages of 4-5 months and 10-11 months. The amount of iron absorption was approximately 0.4 mg/day, calculated as the sum of TBI increment and physiological iron loss. From this study, the dietary iron requirement for the weaning period was estimated as 4 mg/day.

Effects of pre- and postnatal exposure to chlorinated dioxins and furans on human neonatal thyroid hormone concentrations.

Animal studies have shown that dioxins influence plasma thyroid hormone concentrations. To investigate the effect of chlorinated dioxins and furans on thyroid hormone concentrations in humans, we studied 38 healthy breast-fed infants. The study population was divided into two groups according to the dioxin concentrations in milk fat of their mothers. Blood samples were taken at birth and at the ages of 1 and 11 weeks. At birth a tendency to higher total thyroxine (tT4) concentrations was found in the high exposure group. At the ages of 1 and 11 weeks the increase of mean tT4 concentrations and tT4/thyroxine-binding globulin ratios in the high exposure group reached significance as compared to the low exposure group. At birth and 1 week after birth, mean thyrotropin (TSH) concentrations were similar in both groups, but at the age of 11 weeks the mean TSH concentrations were significantly higher in the high exposure group. We postulate that the observed plasma tT4 elevation in infants exposed to dioxins before and after birth is the result of an effect on the thyroid hormone regulatory system.

Effects of Pre- and Postnatal Exposure to Chlorinated Dioxins and Furans on Human Neonatal Thyroid Hormone Concentrations

Animal studies have shown that dioxins influence plasma thyroid hormone concentrations. To investigate the effect of chlorinated dioxins and furans on thyroid hormone concentrations in humans, we studied 38 healthy breast-fed infants. The study population was divided into two groups according to the dioxin concentrations in milk fat of their mothers. Blood samples were taken at birth and at the ages of 1 and 11 weeks. At birth a tendency to higher total thyroxine (tT4) concentrations was found in the high exposure group. At the ages of 1 and 11 weeks the increase of mean tT4 concentrations and tT4/thyroxine-binding globulin ratios in the high exposure group reached significance as compared to the low exposure group. At birth and 1 week after birth, mean thyrotropin (TSH) concentrations were similar in both groups, but at the age of 11 weeks the mean TSH concentrations were significantly higher in the high exposure group. We postulate that the observed plasma tT4 elevation in infants exposed to dioxins before and after birth is the result of an effect on the thyroid hormone regulatory system.

Incidence and Pattern of Jaundice In Healthy Breast-Fed Infants During the First Month of Life

The incidence and pattern of jaundice in 155 normal, full-term, breast-fed, white infants was examined. Infants were screened for jaundice on Days 2, 3, 5, 7, 9, 11, and 13 following birth using transcutaneous bilirubinometry (TcB). By Day 3, 49.7% of the infants were classified as jaundiced (> 10 mg/dl). Infants with low TcB indices on Days 2, 3, and 5 never developed jaundice as indicated by elevated TcB indices on Days 7, 9, 11, and 13. Hence, it may be possible to target infants at risk for severe jaundice prior to discharge. The observed rate of 10.3% for breast-milk jaundice (jaundice present at Day 13) is significantly higher than the highest reported rate of 2.4% (z = 6.43, p < .01). Furthermore, the pattern of jaundice in these infants does not appear to have two peaks, indicating that it is not possible to distinguish between exaggerated physiologic jaundice and breast-milk jaundice using TcB.

Concentration of milk secretory immunoglobulin A against Shigella virulence plasmid-associated antigens as a predictor of symptom status in Shigella-infected breast-fed infants

We conducted a prospective, community-based study of healthy breast-fed Mexican infants to determine the protective effects of anti-Shigella secretory IgA antibodies in milk. Milk samples were collected monthly, and stool culture specimens were obtained weekly and at the time of episodes of diarrhea. Nineteen breast-fed infants were found to have Shigella flexneri, Shigella boydii, or Shigella sonnei in stool samples. Ages of the 10 infants with symptomatic infection and the nine with asymptomatic infection did not differ significantly. Milk samples collected up to 12 weeks before infection were evaluated by enzyme-linked immunosorbent assay for secretory IgA antibodies against lipopolysaccharides of S. flexneri, S. boydii serotype 2, S. sonnei, and virulence plasmid-associated antigens. The geometric mean titers of anti-Shigella antibodies to virulence plasmid-associated antigens in milk received before infection were eightfold higher in infants who remained well than in those in whom diarrhea developed. The significance of milk secretory IgA directed against lipopolysaccharide was less clear. We conclude that human milk protects infants against symptomatic shigella infection when it contains high concentrations of secretory IgA against virulence plasmid-associated antigens.

Fecal Alpha1‐Antitrypsin in Breast‐Fed Infants Is Derived from Human Milk and Is not Indicative of Enteric Protein Loss

Alpha 1-antitrypsin is a serum protein commonly used as a marker of enteric protein loss. In this study, we have quantified alpha 1-antitrypsin concentration in human milk and its excretion by healthy term breast-fed infants. We found high concentrations of alpha 1-antitrypsin in early milk (0.3-0.6 mg/ml during the first week of lactation) while the concentration fell during subsequent weeks, being detectable through at least 3-4 months of lactation. Significant quantities of intact alpha 1-antitrypsin were found to be excreted by the breast-fed infants studied. The amount excreted was typically higher in early weeks (as much as 200 mg/24 h) and decreased with infant age, possibly due to both decreased intake from the milk as well as increased digestion of the protein by the maturing infant. In vitro studies demonstrated that the trypsin-alpha 1-antitrypsin complex resisted proteolysis by pepsin and pancreatic enzymes; thus, alpha 1-antitrypsin in milk can escape gastrointestinal degradation. We conclude that alpha 1-antitrypsin is not a suitable marker for intestinal protein loss by term breast-fed infants.

Vitamin K&lt;sub&gt;1&lt;/sub&gt; Levels and Coagulation Factors in Healthy Term Newborns till 4 Weeks after Birth

Vitamin K1 serum levels were assessed by means of an off-line multidimensional liquid chromatography in 18 mothers, shortly after delivery, and in their healthy term infants. Umbilical cord and venous blood samples were assayed up to 4 weeks of life. Concurrently, levels of coagulation factors II and X, antithrombin III and platelets were established. Although the detection limit of the assay was as low as 22 pg/ml, vitamin K1 concentration appeared to be still beyond that level in cord blood or in newborn serum within 30 min after birth, whereas vitamin-K-dependent coagulation factors are already at a level of 40%, without evidence for the presence of descarboxy prothrombin, in any of the investigated neonates. After 3 days, breast-fed neonates had lower vitamin K1 levels than formula-fed infants (0.76 and 1.44 ng/ml, respectively). The levels of the vitamin-K-dependent coagulation factors II and X, however, were comparable, regardless of the kind of feeding. After 28 days, breast-fed neonates had even lower vitamin K1 levels (0.49 ng/ml, while the formula-fed infants showed higher vitamin K1 levels (4.45 ng/ml). But even then, the levels of vitamin-K-dependent coagulation factors II and X were comparable, regardless of the kind of feeding. From this we conclude that the serum levels of vitamin K1 in formula-fed neonates exceed those of breast-fed infants from the moment of feeding (24 h and later) without a concomitant rise in vitamin-K-dependent coagulation factors. A relationship between vitamin K1 levels and vitamin-K-dependent coagulation factors could not be established in healthy term breast-fed or formula-fed infants.

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.

58 TRACE ELEMENT OVERLOAD IN PKU - DIET?

The knowledge of the trace element requirements of infants fed a phenylalanine restricted diet due to PKU ( Phenylketonuria ) is very limited. We studied 3 infants with PKU under their diet ( Milupa PKU 1 ) longitudinally in balance studies ( ≥ 72 hours ) under home conditions at the age of 2, 5, 8, 12, 16 weeks. Mn, Cu, Fe concentrations in diet, feces and urine were determined by Atomic Absorption Spectroscopy. Median concentrations found in the final diet were 1.7 mg/l Cu, 6 mg/l Fe, 0.5 mg/l Mn. The comparison of the retention rates with the data of 10 healthy breast-fed ( BF ) infants studied before ( s. table (showed a higher range of Mn and Fe retention.The median absolute retention of copper from PKU-diet exceeded that from human milk. Iron supplementation leading to median retentions sixfold the retentions from human milk seems to be unnecessary. Manganese supplementation should be avoided as neither symptoms of deficiency in formula-fed infants have been described nor possible side effects have been excluded.

Normal Serum Bilirubin Levels in the Newborn and the Effect of Breast-Feeding

We measured the serum bilirubin concentrations in 2,416 consecutive infants admitted to our well-baby nursery. The maximum serum bilirubin concentration exceeded 12.9 mg/dL (221 mumol/L) in 147 infants (6.1%), and these infants were compared with 147 randomly selected control infants with maximum serum bilirubin levels less than or equal to 12.9 mg/dL. In 66 infants (44.9%), we identified an apparent cause for the jaundice, but in 81 (55%), no cause was found. Of infants for whom no cause for hyperbilirubinemia was found, 82.7% were breast-fed v 46.9% in the control group (P less than .0001). Breast-feeding was significantly associated with hyperbilirubinemia, even in the first three days of life. The 95th percentile for bottle-fed infants is a serum bilirubin level of 11.4 mg/dL v 14.5 mg/dL for the breast-fed population, and the 97th percentiles are 12.4 and 14.8 mg/dL, respectively. Of the formula-fed infants, 2.24% had serum bilirubin levels greater than 12.9 mg/dL v 8.97% of breast-fed infants (P less than .000001). When compared with previous large studies, the incidence of "readily visible" jaundice (serum bilirubin level greater than 8 mg/dL) appears to be increasing. The dramatic increase in breast-feeding in the United States in the last 25 years may explain this observation. There is a strong association between breast-feeding and jaundice in the healthy newborn infant. Investigations for the cause of hyperbilirubinemia in healthy breast-fed infants may not be indicated unless the serum bilirubin level exceeds approximately 15 mg/dL, whereas in the bottle-fed infant, such investigations may be indicated if the serum bilirubin exceeds approximately 12 mg/dL.(ABSTRACT TRUNCATED AT 250 WORDS)

Fatty acid composition of plasma and erythrocyte phospholipids in preterm infants

Erythrocyte and plasma phospholipid fatty acids were determined in preterm babies at 0, 6 and 10 weeks. There were highly significant changes in fatty acid composition between birth and 6 weeks in both plasma and erythrocyte phospholipids, the changes being more numerous and quantitatively greater in phosphatidyl choline. There was little further change by 10 weeks. Linoleic acid increased by approximately 100% at 6 weeks in plasma phosphatidyl ethanolamine and 200% in phosphatidyl choline. In erythrocyte phosphatidyl ethanolamine, linoleic acid increased by approximately 150% at 6 weeks and in phosphatidyl choline increased 170%. Arachidonic acid decreased by 54%. The essential fatty acid status of the preterm babies studied using contemporary feeding regimes was satisfactory and by 6 weeks phospholipid fatty acid profiles were comparable with published data for normal healthy breast-fed infants.

Changes in plasma lipoproteins from first day to third week of life in healthy breast-fed infants. I. Lipid and protein composition of lipoproteins.

Plasma lipoproteins were measured in seven healthy breast-fed infants three times during the first and on the third, sixth and twenty-first days of life. Plasma total beta-lipoprotein, very low density and low density lipoprotein increased three times during the first week of life. Plasma total apolipoprotein A-I and high density lipoprotein increased twice between the first and third week of life. These dramatic changes in plasma lipoprotein concentrations during the neonatal period can best be explained by the effect of feeding.

Changes in Plasma Lipoproteins from First Day to Third Week of Life in Healthy Breast‐fed Infants

The fatty acid composition of plasma lipoprotein-triglyceride (TG) and -cholesterol ester (CE) was studied in seven healthy breast-fed infants three times during the first day and on the third, sixth and twenty-first days of life. The major finding was a two-fold increase in the linoleic acid weight percent of plasma lipoprotein-TG and -CE between the first and third weeks of life. This increase could best be explained by the ingestion of breast-milk rich in linoleic acid.

Growth of Healthy Breast-fed Infants in the First Six Months-Reply

In Reply .—Regrettably, a typographic error caused the 4.5 g of protein in the article by Hitchcock and colleagues 1 to become 9.5 g of protein when cited in our article. 2 However, we do not believe our interpretation of other aspects of their study was Seriously in error. We cited the study by Hitchcock and colleagues in the context of reviewing studies of breastfeeding which had found growth velocities below national standards. We used data published by the National Center for Health statistics for comparison with the American infants in our sample, while Hitchcock and colleagues used British standards for comparison with the Australian infants in their sample. Although we used different standards, the results of our two studies were quite consistent; breast-fed infants grew more slowly than the standard rate regardless of which standard was used. We did not mean to imply that the breast-fed infants in their sample grew

Infant-initiated weaning from the breast in the first year.

Mothers of 50 healthy breast-fed infants for whom weaning had been completed by the first birthday were administered a maternal feeding and weaning questionnaire developed by the authors. A major purpose of the questionnaire was to investigate the phenomenon of infant-initiated weaning, which is commonly, but somewhat misleadingly referred to as 'self-weaning'. 46% of the infants were reported by their mothers to have initiated weaning. The onset of this behavior occurred most frequently at 5 and 9 months of age. Most mothers attributed it to their infants' increased exploratory and nutritional desires and a concomitant reduced interest in breast-feeding. It is suggested, that rather than being weaning behavior per se, this behavior (at least that which occurs between approximately 5 and 9 months of age) may actually be a common correlate of the cognitive and physical discontinuities or 'spurts' in development which are known to occur during this interval, but that it can, and often does indirectly lead to a relatively easy mutual weaning from the breast if met with appropriate and timely maternal intervention.

Vitamin K-dependent clotting factors in normal breast-fed infants

BREAST-FEEDING has been implicated as a necessary factor in the pathogenesis of hemorrhagic disease of the newborn infant, ~ but little is known of its role in coagulation abnormalities beyond the neonatal period. Vitamin K is approximately four times more concentrated in cow milk than in breast milkfl and clotting factors depending on this vitamin are decreased in normal term infants, and even more reduced in premature infants. 3.4 Deficiency of vitamin K-dependent clotting factors with clinical bleeding has occasionally been reported in breast-fed infants older than one month, but these infants usually had also had diarrhea or had received antibiotic therapy? ,6 Since the levels ot ~ vitamin K-dependent clotting factors in healthy older breast-fed infants have not been systematically assessed, vitamin deficiency cannot be attributed to breast-feeding per se. To determine if breast-feeding during the first month of infancy is associated with an increased risk of bleeding caused by vitamin K deficiency, the present investigation compared coagulation studies and the levels of vitamin K-dependent clotting factors in normal breast-fed and bottle-fed infants.