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The aim of the present study was to examine the effects of breast-feeding method (on only one or on two sides in a single feeding session) on growth, sleep duration and sucking period, and stool frequency. Exclusively breast-fed healthy infants, aged 1-6 months, were included in the study during child health follow-up visits. Mothers were given a questionnaire on sleep duration, sucking periods, and stool frequencies of their infants. The height-for-age and weight-for-age z scores were significantly higher in infants breast-fed from one side during a single session than from both sides (P= 0.002, P < 0.001; respectively). Infants sucking on only one breast in a breast-feeding session defecated significantly less at night (P= 0.005), their maximum sucking periods at night were shorter (P= 0.049). Breast-feeding at one side only during a single breast-feeding session increases growth, decreases stool frequency and the maximum sucking period at night and does not influence the overall sleep pattern.
Original Articleped_2892 817..820
Feeding on one side or both sides in a breast-feeding session
Meda Kondolot,1S. Songül Yalçin2and Kadriye Yurdakök2
1Social Pediatrics Unit, Department of Pediatrics, Erciyes University Faculty of Medicine, Kayseri and 2Social Pediatrics
Unit, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
Abstract Background: The aim of the present study was to examine the effects of breast-feeding method (on only one or on two
sides in a single feeding session) on growth, sleep duration and sucking period, and stool frequency.
Methods: Exclusively breast-fed healthy infants, aged 1–6 months, were included in the study during child health
follow-up visits. Mothers were given a questionnaire on sleep duration, sucking periods, and stool frequencies of their
Results: The height-for-age and weight-for-age z scores were significantly higher in infants breast-fed from one side
during a single session than from both sides (P=0.002, P<0.001; respectively). Infants sucking on only one breast in
a breast-feeding session defecated significantly less at night (P=0.005), their maximum sucking periods at night were
shorter (P=0.049).
Conclusion: Breast-feeding at one side only during a single breast-feeding session increases growth, decreases stool
frequency and the maximum sucking period at night and does not influence the overall sleep pattern.
Key words breast-feeding method, defecation, growth, sleep, sucking period.
Breast-feeding has been the key for the survival of the human
species and its exclusive supply, for at least the first 6 months of
life, should be provided to every infant.1–5 Mothers of healthy
babies who are breast-feeding should have no restrictions placed
on the frequency or length of their babies’ breast-feed. They
should be advised to breast-feed their babies whenever they are
hungry or as often as the baby wants.3,6 Fixed breast-feeding
schedules were introduced at the beginning of the 20th century in
an attempt to make infant feeding scientific and safe.7–9 These
ideas still prevail in some places, but more generally it is now
accepted that scheduling feeds leads to breast-feeding problems
and insufficient milk production, which may cause mothers to
start artificial feeding. Restricting feed length may result in the
baby getting less of the energy-rich hindmilk.10 With demand
feeding, also known as ‘unrestricted’ or ‘baby led’ or ‘in response
to the baby’s cues’, the frequency and length of feeds varies both
between infants and from day to day.11 Breast-feeding from the
first breast should be unlimited in time and both breasts need not
be routinely used at each feed.12
Various programs are currently being carried out to promote
breast-feeding,4as well as to investigate the impact of breast-
feeding methods, duration, and frequency of breast-feeding on
mother–infant pairs. The best method is baby-led breast-feeding.
Recommended breast-feeding starts with the breast not used in
the last breast-feeding period and continues until the infant stops
sucking; thus, it is ensured that the infant takes the hindmilk and
there is no need to offer the second breast unless the infant wants
it, which is again determined by the infant itself.10–13 Despite this
advice on breast-feeding method, there are limited studies on
infants fed on one side or both sides at a single feeding
The aim of the present study was therefore to compare infants
fed one or both breasts in a single feeding session in terms of
weight gain, sucking period in a breast-feeding session, sleep
duration, and stool frequency.
The study group included exclusively breast-fed healthy infants,
aged 1–6 months, who were admitted to Department of Social
Pediatrics of the Institute of Child Health at Hacettepe University
between October 2007 and February 2008 for child health
follow-up visits. This is a descriptive study and mothers were
asked to describe their babies’ breast-feeding method. Feeding
pattern was not taken into consideration in the first 15 days. After
the 15 day postpartum period, infants taking only one breast in a
breast-feeding session were included in group S (n=105), infants
taking both breasts within 30 min of the session formed group D
(n=82). Infants using both breast-feeding methods, that is, one
breast in one session and both in the other one, infants with
partial breast-feeding or bottle feeding and infants who were
hospitalized, were not included in the study. We enrolled volun-
tary mothers if they fulfilled all entry criteria. Two hundred and
ten mothers fulfilled all entry criteria and 187 (89%) agreed to
participate in the interview. Mothers participating in the study
Correspondence: Meda Kondolot, MD, Erciyes University Faculty of
Medicine Department of Pediatrics, Unit of Social Pediatrics, 38010,
Kayseri, Turkey. Email:
Received 19 September 2008; revised 17 March 2009; accepted 24
March 2009.
Pediatrics International (2009) 51, 817–820 doi: 10.1111/j.1442-200X.2009.02892.x
© 2009 Japan Pediatric Society
were given a questionnaire regarding their educational status and
sociodemographic characteristics of the family, and the infants’
age, sex, gestational week, birth order, birthweight, sucking
periods and sleep durations during the day and night, stool fre-
quencies, pacifier use, and unusual crying.
Anthropometry was measured on admission of the infants and
their previous measurements, if any, were recorded from their
files. Only recorded measurements were taken into consideration.
They were evaluated using the World Health Organization Mul-
ticentre Growth Reference Study (MGRS).15
Statistical analysis
All analyses were compared using SPSS for Windows (SPSS,
Chicago, IL, USA). The normality of data distribution was
checked using the Kolmogorov–Smirnov test. To compare
means, Student’s t-test was used for data with normal distribution
and Mann–Whitney U-test for skewed data. Covariance analysis
was used to detect the differences between group S and group D
for height-for-age and weight-for-age z scores after adjusting
birthweight, maternal education and maternal smoking and, for
birthweight after adjusting maternal education and maternal
smoking. The difference of case distribution between the groups
was analyzed using c2test. Fisher’s exact test was used when
applicable. P<0.05 was considered significant.
Of the exclusively breast-fed infants who were included in the
study, 105 were breast-fed at one side only during a single
feeding session (group S), and 82 were breast-fed on both sides
(group D). The factors of age, gestational age, birthweight, sex,
maternal educational status, maternal smoking and birth order
were similar in both groups (Table 1). In group D birthweight
(and weight-for-age z score at birth) was slightly lower, maternal
smoking rate was higher and the level of maternal education was
lower than group S, but these are not statistically significant (P>
0.05). After adjusting for maternal education level and maternal
smoking, no differences were detected in terms of birthweight
and z scores between the groups.
Although there were no significant differences between the
two groups in terms of birthweight, it was detected that height-
for-age and weight-for-age z scores of group S were significantly
higher than those for group D (P=0.002, P<0.001, respec-
tively). No significant difference, however, was found with regard
to weight-for-height z scores (Table 2). After adjusting for birth-
weight, maternal education and maternal smoking, significant
differences were found in height-for-age and weight-for-age z
scores of group S and group D (height-for-age z score [mean 1
SEM]: 0.63 10.09, 0.17 10.10 P=0.001; weight-for-age z score
[mean 1SEM]: 0.73 10.07, 0.34 10.09, P=0.001, respectively).
Stool frequency at night was found to be significantly lower in
group S than group D (P=0.005). The mean maximum sucking
period in a breast-feeding session at night was significantly lower
in group S (P=0.049). The mean maximum daytime sucking
period in a breast-feeding session was shorter in group S (19 min)
than group D (21 min), but the difference was not significant.
Sleep duration was similar in the two groups. No difference was
observed between the groups in terms of pacifier use and unusual
crying (Table 2).
Current recommendation is to feed babies on demand, therefore
there is no prescribed pattern to breast-feed babies.16 During a
breast-feeding session, the baby may feed from one breast only,
feed from both breasts within 30 min, or the baby may have a
cluster of breast-feeds (feeding again from the first breast within
30 min of feeding on the second).17 In a recent study of exclu-
sively breast-feeding infants between 1 and 6 months old in
Western Australia, 13% of infants always took both breasts, 30%
of infants always took one breast, and 57% of infants alternated.14
Breast milk lipids provide approximately 50% of the calories
in the milk, and the lipid content of breast milk increases through
a single feeding session from foremilk to hindmilk. Foremilk is
watered down milk, which is thirst-quenching, high in lactose but
low in fat and protein.18 It is known that the fat content of human
milk increases along with the emptying of the breast,19,20 while
other macronutrient compositions seem to change only slightly
or not at all.19,21 Hindmilk contains two–threefold the amount of
fat compared to foremilk, consequently supplying 104–146 kJ/
100 mL more energy, on average, than foremilk.21 Babies taking
hindmilk, rich in fat, although sucking one breast only during a
breast-feeding session are usually satisfied and do not want to
suckle the second breast. Ogechi et al. have shown that preterm,
very low-birthweight babies fed hindmilk gain weight signifi-
cantly faster than those fed composite milk.18
In the present study weight-for-age and height-for-age z
scores were significantly higher in infants breast-fed from one
Table 1 Infant characteristics vs breast-feeding method in a single
feeding session*
Fed one side only
Fed both sides
Age (months), mean 1SD 2.86 11.25 2.65 11.52
Male infants 62 (59) 43 (52)
Gestational age (weeks),
mean 1SD
38.47 11.31 38.39 11.38
Birth order
First child 61 (58) 42 (51)
Second 36 (34) 36 (44)
Third or higher range 8 (7.6) 4 (5)
Maternal education (years)
<11 9 (8.6) 13 (15.9)
311 96 (91.4) 69 (84.1)
Smoking at home
Yes 36 (34.3) 31 (37.8)
No 69 (65.7) 51 (62.2)
Maternal smoking
Yes 9 (8.6) 14 (17.1)
No 96 (91.4) 68 (82.9)
Birthweight (g), mean 1SD 3300 1434 3213 1424
Weight-for-age z score
(at birth), mean 1SD
-0.04 10.93 -0.21 10.91
*P>0.05 for comparison between groups.
818 M Kondolot et al.
© 2009 Japan Pediatric Society
side than both sides, but there was no significant difference
between the two groups in terms of the weight-for-height z
scores. This situation has been attributed to the fact that the
hindmilk intake was fully completed in infants fed from one
breast only during a single breast-feeding session and thus, their
energy and calorie intake were higher than those infants breast-
fed from both sides and subsequently fed more foremilk richer in
lactose, with less fat content; causing their weight gain to be
lower when compared to the other group fed only one breast. This
is supported by the fact that there was no difference between the
birthweight-for-age z scores of the two groups. Furthermore, it
has been suggested that breast-feeding protects infants from
becoming overweight or obese. Although the precise magnitude
of this association remains unclear, several biological mecha-
nisms could explain the association. It was reported that breast-
feeding affects intake of calories and protein; insulin secretion;
and modulation of fat deposition and adipocyte development.22,23
Buyken et al. suggested that breast-feeding could offset a poten-
tial programming effect for childhood adiposity.24
Foremilk, poorer in fat content and calories than hindmilk, but
larger in volume, immediately fills up the stomach capacity,
which is still small in babies, leading to shorter gastric discharge
periods and more stool output in infants fed both sides. Because
the baby is not satisfied due to the relatively low fat content, the
infant continues sucking for a longer time and quickly gets
hungry. Also both stool frequency and the risk of the infantile
colic might be higher due to the lactose-rich content. In the
present study, defecation frequency of infants fed on one breast at
night were significantly lower than in the other group (P=0.005).
These results confirm those of previous studies.25,26 No significant
relationship, however, has been detected between unusual crying
and breast-feeding from one or both sides during a single feeding
session. Furthermore, the mean of maximum sucking periods at
night in infants fed on one side was significantly shorter than that
of infants fed on both sides (P=0.049). Daytime maximum
sucking periods were also shorter in infants fed on one side only,
but the difference was not significant. It was suggested that these
infants were quickly satisfied due to their intake of hindmilk and
completed sucking in a shorter period of time.
Because of the aforementioned reasons, it was also suggested
that the sleep duration of infants fed on both sides was shorter,
causing them to get hungry more quickly, and initiate colic
attacks, but impact of the difference in breast-feeding method on
sleep duration and infantile colic was detected. This may be due
to the limited number of cases involved.
In some studies it was demonstrated that pacifier use short-
ened both sucking period in a breast-feeding session and duration
of breast-feeding.27–30 It has been shown that the sucking periods
during 24 h in infants who used pacifiers during the first 4 months
were 15–30 min shorter than in those who did not use pacifiers,
and that they sucked less in a daily feeding session.30 The plau-
sible explanation for this is that mostly pacifier use within the
first months of life hinders breast-feeding.11 In the present study
no difference was found for pacifier use in the two groups.
Because breast-feeding period and frequency are preferably
baby led, it is wise to ensure that the first breast in each breast-
feeding session is fully emptied by the infant, because that will
help the infant to obtain hindmilk, which is richer in fat and
calories. This will enhance the growth in infants fed on one breast
only during a single feeding session. Also the maximum sucking
periods are shorter; and the stool frequency lower.
1 World Health Organization (WHO). Exclusive Breastfeeding.
[Accessed July 2008.] Available from:
2 Kamudoni P, Maleta K, Shi Z, Holmboe-Ottesen G. Infant feeding
practices in the first 6 months and associated factors in a rural and
semiurban community in Mangochi district, Malawi. J. Hum. Lact.
2007; 23: 325–32.
Table 2 Height and weight vs breast-feeding method during a single feeding session
Fed one side only
Mean 1SD (median)
Fed both sides
Mean 1SD (median)
Height for age (z score) 0.65 11.06 (0.74) 0.14 11.13 (0.28) 0.002
Weight for age (z score) 0.77 10.82 (0.67) 0.28 11.00 (0.30) <0.001
Weight for height (z score) 0.51 10.96 (0.47) 0.33 11.06 (0.24) n.s.
Stool frequency in daytime 3.09 11.86 (3) 3.05 12.04 (3) n.s.
Stool frequency at night 0.64 10.78 (0) 1.03 10.98 (1) 0.005
Sleep duration (min)
Night-time 520 180 (480) 499 185 (480) n.s.
Daytime 331 1142 (360) 350 1121 (360) n.s.
Maximum sucking period in a breast-feeding session (min)
Night-time 16 17 (15) 20 112 (17.5) 0.049
Daytime 19 110 (15) 21 113 (17.5) n.s.
Minimum sucking period in a breast-feeding session (min)
Night-time 8 15 (5) 9 16 (5) n.s.
Daytime 8 16 (5) 7 15 (5) n.s.
Pacifier use, n(%) 36 (34.3) 30 (36.6) n.s.
Unusual crying, n(%) 30 (28.6) 30 (36.6) n.s.
daytime, 08.00–20.00 hours; night-time, 20.00–08.00 hours; n.s., not significant.
Breast-feeding method 819
© 2009 Japan Pediatric Society
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Young Child Feeding. WHO, Geneva, 2003.
4 Hannula L, Kaunonen M, Tarkka MT. A systematic review of
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6 WHO/UNICEF. Baby Friendly Hospital Initiative. Part II. Hospi-
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8 Klaus MH. The frequency of suckling. A neglected but essential
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© 2009 Japan Pediatric Society
... 2,3 Ülkemizde anne sütü ile beslenmenin dışkılama özellikleri üzerine etkisini inceleyen çalışma sayısı oldukça azdır. [4][5][6] Mevcut araştırmalar da anket çalışması olup, dışkının mikroskobik değerlendirmesi ve laboratuvar incelemelerini içermemektedir. Bu çalışmada; bir çocuk sağlığı izlem polikliniğine getirilen ve anne sütü ile beslenen 0-6 aylık bebeklerin dışkılama özelliklerinin tanımlanması amaçlanmıştır. ...
Objective: Normal defecation pattern is one of the health indicators for children. Stool number and patterns in children can show differences depending on factors such as age and feeding type. To know normal defecation patterns prevents unnecessary treatment via distinguishing normal defecation from abnormal and reduces health costs via informing parents who have serious concerns about this issue. The aim of this study was to investigate the effect of breast feeding on defecation pattern of 0-6 months-old breast-fed infants. Material and Methods: The study was carried out at Well Child Clinic of the Istanbul Medical School in Istanbul University, between June 2010 and January 2011 and included 100 infants aged 0-6 months. A structured questionnaire was filled on the day when families arrived at the Well Child Clinic and infants' anthropometric measurements were recorded. Stools that infants passed in the last 24 hours were collected and analyzed in the laboratory. Color, consistency, pH and steatocrit of stools were evaluated. Data analyses were performed in SPSS 15.0 and SigmaStat 3.5 programs. Significance level was accepted as p>0.05 in statistical comparisons. Results: Seventy four percent of infants defecated daily. Stool frequency of infants decreased with age and infants breastfed in frequent intervals defecated more frequently (p>0.05). Exclusively breast-fed infants had more frequent defecation than the ones receiving complementary foods/formula in addition to breast milk. Conclusion: In conclusion, our results led us to think that defecation and growth patterns of infants aged 0-6 months show diversity according to the age and feeding characteristics.
Full-text available
Curtailing the time for which a baby feeds at the first breast, in order to encourage intake from the second breast, may maximise milk production by the mother. With escalation of this situation a point may be reached at which the infant, because of the constraint of his stomach capacity, is unable to consume sufficient calories at a feed, since foremilk is lower in calories than hindmilk. The result will be symptoms of hunger (crying, fretfulness) and maybe even failure to thrive. The low fat content of the diet may cause rapid gastric emptying. This in turn may lead to lactose reaching the small bowel in concentrations that may tax the infant's lactase potential, with resulting diarrhoea. A simple change in breastfeeding patterns may alleviate some instances of undernutrition or diarrhoea.
Full-text available
Within-feed and between-breast differences in the concentrations of sodium, potassium, chloride, calcium, magnesium, lipid, protein, lactose, glucose, urea nitrogen, creatinine, zinc, and copper were examined in milk samples from 10 women. The average lipid content doubled in the interval from the beginning of the feed to the end. The composition of the aqueous phase of milk, as determined by the major osmotically active constituents, did not vary significantly within the feed. For these components as well as for lipid a small mid-feed sample of milk gave the same mean composition as the pooled, pumped contents of one breast suggesting that such a sample is adequate for determination of milk composition in population studies. Sporadic, inconsistent differences in the composition of the milk from the right and left breasts were observed. It is suggested that mastitis may contribute to these differences. It is recommended that samples routinely be taken from both breasts and analyzed for sodium and chloride to rule out episodes of mastitis or other local phenomena which sporadically alter milk composition.
This article presents data to suggest that an essential ingredient for the success of breast-feeding is feeding frequency. Increasing the frequency of feeding decreases nipple pain and breast tenderness, significantly increases milk output and infant weight gain, decreases the peak serum bilirubin levels, increases the success of lactation, and decreases ovulation, markedly improving the contraceptive effect of breast-feeding.
We have devised a method for the determination of the composition of the milk infants obtain from the breast during suckling itself, suckled breast milk (SBM). The method involves the use of a nipple-shield sampling system, together with data on the pattern of milk flow from mother to infant derived from a cross-sectional analysis of test weighings during feeding. In this study, marked changes were demonstrated in milk fat the sixth day postpartum. From this information the total intake of fat and energy during the feed was calculated. These preliminary findings suggest that published information on the dietary intake of breast-fed infants may need some revision.
To determine the relationship between pacifier use at 1 month of age to the duration of breast-feeding to 6 months of age. Longitudinal study of infants from birth to 6 months of age. Six hundred five rooming-in infants born at the largest hospital in Guarujá, São Paulo, Brazil, during January and February 1993. Prevalence of breast-feeding (exclusive, predominant, and complementary) at 1, 4, and 6 months of age. Relative risk for weaning between 1 and 6 months of age was 3.84 (95% confidence interval 2.65-5.50) for pacifier users at 1 month of age, compared with nonusers. When an adjustment was made for possible confounding variables through Cox regression analysis, the relative risk dropped to 2.87 (95% confidence interval 1.97-419). Pacifier use is highly correlated with early weaning, even after controlling for possible confounders. Until it is determined if pacifier use is causally related to weaning or is a marker for other undetermined causes, pacifier use probably should not be recommended for breast-fed infants.
Control data from 1529 infants studied in a multicentre case-control study of sudden infant death in New Zealand were analysed to identify factors that might hinder the establishment and duration of breast feeding. Although 1300 infants (85%) were exclusively breast-fed at discharge from the obstetric hospital, this fell to 940 (61%) by 4 weeks. Logistic regression was used to identify factors that might adversely influence breast feeding 'at discharge', 'at 4 weeks' and the overall 'duration' of breast feeding. When adjusted for confounding factors, not exclusive breast feeding 'at discharge' was significantly associated with: twin pregnancy, being a Pacific Islander, mother not bedsharing, subsequent dummy use, birthweight less than 2500 g, heavy maternal smoking, not attending antenatal classes and mother less than 20 years old at first pregnancy. Mothers smoking more than 20 cigarettes a day were nearly twice as likely to not exclusively breast feed on discharge compared to those who did not smoke. A 'dose response' was apparent with the heaviest smokers having the least likelihood of establishing exclusive breast feeding. Being exclusively breast-fed at discharge but not 'at 4 weeks' was associated with: twin pregnancy, admission to a neonatal intensive care unit, subsequent dummy use and not being married. A shorter overall 'duration' of breast feeding was associated with maternal smoking, subsequent dummy use, mother not bedsharing, twin pregnancy, mother less than 20 years old at first pregnancy, low occupational status and not attending antenatal classes. These effects persisted when social and demographic factors, including birthweight, were taken into account.(ABSTRACT TRUNCATED AT 250 WORDS)
Intake and growth were compared between matched cohorts of infants either breast-fed (BF) or formula-fed (FF) until > or = 12 mo of age. Total energy intake at 3, 6, 9, and 12 mo averaged 0.36, 0.34, 0.35, and 0.38 (85.9, 80.1, 83.6, and 89.8 among BF infants vs 0.41, 0.40, 0.39, and 0.41 (98.7, 94.7, 93.6, and 98.0 among FF infants, respectively. Protein intake was 66-70% higher in the FF than in the BF group during the first 6 mo. Differences in energy and protein intakes were significant at 3, 6, and 9 mo. Gains in weight and lean body mass were lower in BF than in FF infants from 3 to 9 mo. BF infants gained more weight and lean body mass per gram protein intake but not per megajoule intake. Although growth differences between groups were related to differences in intake, there is no evidence of any functional advantage to the more rapid growth of FF infants.