Breastfeeding is a practice that has been around for thousands of years
and which offers well-known nutritional, immunological, cognitive, economic and
social benefits. These benefits are only taken advantage of to the full when breastfeeding
continues for at least 2 years, being the sole means of feeding infants for their
first six months of life.
Studies conducted nationally have shown that, despite a tendency towards improvement,
breastfeeding rates in Brazil are well below the levels considered ideal by the
World Health Organization (WHO).
into demographic and socioeconomic variables and factors related to healthcare
and to the habits of mothers and babies on a populational level can be of great
utility to identifying factors related to duration of exclusive breastfeeding
or complementary feeding. They can, therefore, be useful tools in the quest to
increase breastfeeding rates in our country. Nevertheless, regional differences
in breastfeeding practices underscore the need for focused diagnoses that can
guide the taking of intervention measures aimed at promoting, supporting and protecting
The objective of this study was to determine rates of exclusive
breastfeeding and of complementary feeding and to identify variables that possibly
interfere with breastfeeding practices in Itaúna, MG, Brazil.
This was a longitudinal study of women who gave birth at the maternity unit
of the Manoel Gonçalves de Souza Moreira Hospital, which is the only hospital
in the municipality of Itaúna. Itaúna is located 72 km from Belo
Horizonte, in the metalworking zone of midwestern Minas Gerais state and has approximately
80,000 inhabitants. The hospital's clientele come from a variety of social strata,
but classes with lower purchasing power predominate. Mothers and their babies
were followed for the first 12 months after delivery or until breastfeeding ceased
if this took place first.
This article was extracted from a more extensive
research project that aimed to assess the influence of medication on breastfeeding
duration. In response to the non-existence of parameters from which to calculate
sample size, the following values were adopted: 5% level of significance (a);
power (1-b) of 90%; subjects enrolled for 3 months;
subjects followed up for 12 months after enrollment, losses of 20%; a 30% probability
of that mothers on medication would be breastfeeding at the end of the study and
a probability of 70% for those not medicated; and a probability of being on medication
of 25%. Based on these parameters, the sample size was calculated at 252 mothers.
sample was selected between 1 June 2003 and 4 September 2003 and included mothers
resident in Itaúna who gave birth at the hospital's maternity unit. From
the total number of subjects the following were lost: five mothers could not be
located for the first interview after hospital discharge and one whose child died
40 hours after birth. A further eight of the 246 women initially enrolled were
lost to follow-up; five because they moved away from the town; three because they
could not be found; and 83 were censored due to the ending of the study. Therefore,
accurate information about duration of overall breastfeeding was obtained from
Data collection was carried out at the maternity unit by the
researcher in conjunction with members of the Universidade de Itaúna Physiotherapy
Department. These academics were trained to apply the questionnaires during interviews
with 20 mothers as part of a pilot study. Quality control was carried out at weekly
meetings for the first 8 weeks of data collection and fortnightly thereafter.
of interest were obtained from medical records and interviews conducted during
the immediate postnatal period. These data will provide information on demographic
and socioeconomic characteristics and factors related to healthcare services and
mothers' and babies' habits. After discharge from the maternity unit, mothers
were followed up by means of contact by telephone or by home visits.
variables studied were as follows: origin; health insurance; maternal age; skin
color; marital status; breast surgery; number of pregnancies and births; gestational
age; prenatal care; family income and electricity consumption; basic sanitation;
maternal and paternal education; maternal employment; maternity leave; family
support; knowledge of breastfeeding techniques; intention of breastfeeding; time
passed between birth and first breastfeed; use of medication, alcohol and tobacco
by mother; use of a pacifier; intercurrent conditions; sex and birth weight of
The following WHO definitions of breastfeeding categories were adopted
for this study:
breastfeeding: the child is fed exclusively on human milk from its mother or wet-nurse,
or on expressed milk, with no other liquids or solids, with the exception of drops,
syrups, mineral supplements and medications; -predominant breastfeeding : the
child is fed on human milk and other liquids, such as water, teas, fruit juices
and medications, but receives no other type of milk;
exclusive breastfeeding plus predominant breastfeeding;
the child is fed on human milk and other solid or semi-solid foods;
the child is fed human milk (from the breast or expressed) irrespective of whether
or not other foods are also given.
The term full weaning was
adopted to describe complete cessation of breastfeeding.
project was approved by the Ethics Committee at the Manoel Gonçalves de
Souza Moreira Hospital, the UFMG Pediatrics Department and the UFMG Research Ethics
Statistical analysis of the data was carried out using SPSS,
version 9.0. Survival analysis procedures were applied to duration of exclusive
breastfeeding and breastfeeding. Breastfeeding curves were plotted using the Kaplan-Mayer
method, which provides medians for duration of exclusive breastfeeding and of
breastfeeding. Curves were compared using log rank testing. The effect of co-variables
on breastfeeding duration was assessed using Cox regression modeling. Variables
were included in the multivariate regression model if they exhibited a correlation
with an outcome with p < 0.25 in the bivariate analysis. The cutoff for significance
was set at 5%.
of exclusive breastfeeding and of breastfeeding
All of the women
were breastfeeding at the time of hospital discharge, although only 241 (98%)
were doing so exclusively. Prevalence rates of exclusive breastfeeding at the
first, fourth and sixth months of life were 62.6, 19.5 and 5.3% respectively.
Full breastfeeding rates for the same periods were 77.2, 42.3 and 15%. Prevalence
rates of overall breastfeeding for the first, fourth, sixth and twelfth months
were 93.5, 75.2 58.9 and 33.7%, respectively (Figure 1).
Figure 1 -
rates for exclusive breastfeeding, full breastfeeding and breastfeeding in Itaúna,
MG, Brazil, 2003
Median duration of exclusive breastfeeding was 40 days,
and for full breastfeeding it was 95 days. Median duration of breastfeeding was
Factors related to exclusive breastfeeding
to the bivariate analysis, variables that exhibited positive, statistically significant
associations with shorter duration of exclusive breastfeeding were: birth weight
of child < 2,500 g (p = 0.03), incorrect answer to question on breastfeeding
technique (p = 0.012), intention to breastfeed for less than 2 years (p = 0.009),
use of alcohol or tobacco (p = 0.036) and use of a pacifier (p = 0.002).
can be observed in Table 1, after the multivariate analysis, variables with statistically
significant (p < 0.05) negative associations with duration of exclusive breastfeeding
were: intention to breastfeed for less than 2 years (p = 0.002), birth weight
of child < 2,500 g (p = 0.019) and use of a pacifier (p = 0.007).
Variables related with duration of exclusive breastfeeding (p < 0.05) according
to multivariate analysis, Itaúna, MG, Brazil, 2003
related to breastfeeding
According to the bivariate analysis, variables
that exhibited negative statistically significant associations with duration of
breastfeeding were: maternal age less than 20 years (p = 0.001), gestational age
< 37 weeks (p = 0.039), less than five or more than nine prenatal consultations
(p = 0.002), first suckled more than 6 hours after birth (p = 0.032), newborn
with intercurrent condition (p = 0.001), use of alcohol or tobacco (p = 0.001)
and use of a pacifier (p = 0.000).
The multivariate analysis demonstrated
positive, statistically significant associations between shorter breastfeeding
duration and the following variables: maternal age less than 20 years (p = 0.009),
less than five or more than nine prenatal consultations (p = 0.001), use of alcohol
or tobacco (p = 0.001), first suckled more than 6 hours after birth (p = 0.038)
and use of a pacifier (p = 0.000). These results are listed in Table 2.
Variables related to breastfeeding duration (p < 0.05) according to multivariate
analysis, Itaúna, MG, Brazil, 2003
findings of this study were compared with published data, in particular with the
results of population studies undertaken in towns geographically and demographically
similar to Itaúna, although there are methodological and temporal differences
between studies. Since the town has only one hospital, where almost all births
take place, the sample can be considered representative of this population.
Itaúna, the prevalence of exclusive breastfeeding at the end of the sixth
month of life (5.3%) was similar to prevalence rates observed in Ouro Preto
(1.8%), Alto Jequitinhonha
(0.8%) and Embu
(1.6%), although lower than the 17.7% found in Feira de Santana.
The prevalence of breastfeeding at 12 months, however, was lower than that observed
in Ouro Preto
(34.9%), Montes Claros
(41%) and Feira de Santana
(69.2%), but higher than the prevalence of 30% found in Embu.
duration of exclusive breastfeeding was 40 days, an intermediate position in relation
to other Brazilian locations. This figure is worrying, because it demonstrates
that foods such as water, teas and juices are being introduced prematurely. It
is known that such supplements are unnecessary for babies' hydration needs,
increase the risk of morbidity and mortality by infections,
do not improve weight gain
and reduce uptake of iron and zinc.
Premature introduction of these and other supplementary foods, as well as complementary
ones such as non-human milk, fruit and savory mashes, can reduce the contraceptive
efficacy of lactational amenorrhea and also reduce breastfeeding duration.
Furthermore, premature use of cow's milk is linked with increased risk of atopic
diseases and diabetes mellitus type I.
The great frequency with which supplementary and complementary foods are being
used may be the result of cultural factors and of ignorance on the part of some
health professionals of the benefits of exclusive breastfeeding until the sixth
month of infants' lives.
The median duration of breastfeeding observed in
Itaúna was 237 days, which is longer than the medians of 159 days in Alfenas,
180 days in Embu,
198 days in Ouro Preto
and 205.9 days in São José9; do Rio Preto.
It is still, nevertheless, shorter than the median durations of 261 days in Montes
and 325.5 days in towns in Alto Jequitinhonha.
The medians for exclusive breastfeeding and for breastfeeding in Itaúna
confirm the tendency to increase these rates in our country. Nevertheless, they
are well below what is recommended by the WHO.
negative relationship between birth weight < 2,500 g and duration of exclusive
breastfeeding has also been described in other studies.
The fact that low birth weight infants are exclusively breastfed for shorter periods
than other infants may be the result of the increased difficulty that such babies
have in suckling and also because of the belief on the part of some health professionals
that the most important factor with such babies is weight gain and so infant formulae,
powdered milk, cow's milk and sugar are given. This being so, in order to increase
exclusive breastfeeding rates it is necessary to give greater attention to preventing
conditions that make it more likely babies will be born at low weights, such as
intrauterine growth restriction and premature delivery, in addition to taking
measures to improve prenatal care and to reduce smoking during pregnancy. The
Kangaroo Mother Care system results in greater physical and emotional contact
between low weight newborn infants and their mothers and has been described as
an action with a positive impact on breastfeeding.
Another indispensable intervention is to improve the care provided by health professionals
responsible for infant health to this group of mothers and babies, in the form
of encouraging and supporting exclusive breastfeeding.
The fact that mothers
who expressed the intention in the maternity unit of breastfeeding their children
for less than 2 years exhibited shorter exclusive breastfeeding duration may by
because these women were less well informed on the importance of breastfeeding
and more exposed to external pressures. Furthermore, it can be postulated that
mothers whose intention is to breastfeed for shorter periods are less committed
to following medical guidance on duration of exclusive breastfeeding. No reports
were found in the literature relating this variable with duration of exclusive
The fact that adolescent women (< 20 years) breastfed
their children for shorter periods coincides with data published by Gigante et
That adult women breastfeed for longer may be due to greater experience and knowledge
of breastfeeding. This should alert us to the need for greater care and attention
to adolescent mothers, aiming to provide guidance, encouragement and support for
breastfeeding. Wider dissemination of sexual education information could contribute
to a reduction in the frequency of adolescent pregnancies.
Women who attended
less than five and more than nine prenatal consultations breastfed their children
for a shorter period than mothers who attended between five and nine consultations.
Caldeira & Goulart,
in Montes Claros, observed that women who attended less than five consultations
breastfed for a shorter duration than those who attended more than five (p = 0.0496),
although only in a bivariate analysis. The fact that women who attended less than
five prenatal consultations breastfed their children for a shorter period may
be related to reduced access to the information provided during the prenatal period.
Nevertheless, the association between a greater number of prenatal consultations
and shorter duration of breastfeeding cannot be satisfactorily explained. However,
one could speculate that these women suffer from a greater degree of anxiety and
insecurity. In order to better explain this finding, it would be necessary to
engage in a deeper study of this subset of patients, including the use of qualitative
The shorter duration of breastfeeding when newborn infants
were suckled for the first time more than 6 hours after being born has also been
reported by Caldeira & Goulart
in Montes Claros. Bautista
also described a positive relationship between shorter delay before first feed
and longer duration of breastfeeding. Figueiredo & Goulart
noted a positive association between lower rates of full weaning and increased
number of women who were not separated from their children during the first 6
hours after birth. This fact can be explained by the beneficial effect of this
first contact for the mother, leading to increased liberation of oxytocin, favorable
to milk ejection, in addition to the lactogenic effect of the baby's suction.
Furthermore, the importance of early contact has also been linked to strengthening
the emotional bond between mother and child, which may also be responsible for
increased breastfeeding duration.
The fact that babies who start feeding early are breastfed for longer demonstrates
the important role that hospital practices can play in the success of breastfeeding,
reinforcing the importance an integrated rooming-in policy, allowing mother and
child to remain together throughout their hospital stay.
who reported in the maternity unit that they used alcohol and tobacco breastfed
had shorter breastfeeding duration than those who said they did not use these
drugs. Despite evidence that smoking while breastfeeding is less prejudicial than
feeding with industrialized milk,
the majority of published data links maternal smoking with shorter duration of
Furthermore, both smoking and alcohol use have been reported to be linked with
reduced volume of breastmilk.
Although the American Academy of Pediatrics (AAP)
considers alcohol to be compatible with breastfeeding and permits the use of tobacco,
the results of our study reinforce the importance of reducing the use of these
substances by women, particularly nursing mothers. Physical and psychological
factors linked to pregnancy and breastfeeding make these ideal moments for health
professionals to indicate cessation of alcohol and tobacco use.
Use of pacifiers
by infants was negatively associated with duration of both exclusive breastfeeding
and overall breastfeeding. The analysis took account solely of whether or not
the child was given a pacifier, not identifying frequency or time of usage. The
fact that babies who did not use a pacifier had longer duration of exclusive breastfeeding
is in agreement with published data.
This fact may be related to greater confidence on the part of mothers whose babies
were not given pacifiers, being less sensitive to social pressures and less anxious
about their children's growth rate. Furthermore, pacifiers may be related to reduction
in milk production, as a result of reduced frequency of feeds.
Silveira & Lamounier
performed a review of the literature on studies that associate pacifiers with
shorter breastfeeding duration. All eight studies found reported a statistically
significant association. Soares et al.
found a 2.8 times greater risk of full weaning before the sixth month by children
who were still being breastfed at 1 month, but who were using a pacifier. Therefore,
the pacifier use may be camouflaging breastfeeding difficulties or maternal anxiety
and insecurity about the feeding process, facts which should alert us to the need
to solve such problems. It is to be desired that studies be carried out to evaluate
this theme in greater depth, including the use of qualitative assessment methods.
Therefore, mothers should be better informed of the serious consequences for successful
breastfeeding of giving pacifiers to infants - a habit that is apparently innocuous
and which is very much culturally acceptable.
The determination of indicators and variables related to exclusive
or overall breastfeeding duration can be a valuable instrument when planning local
actions and policies aimed at improving breastfeeding rates. This study, in common
with other Brazilian studies, demonstrates that breastfeeding rates are well below
those recommended by the WHO. It also reveals that the principal variables negatively
related with duration of exclusive breastfeeding and complementary feeding are
susceptible to intervention. Therefore, improving the quality of the healthcare
provided to mothers and their babies can be considered an extremely important
measure for increasing breastfeeding rates.