The British Journal of Developmental Disabilities
Vol. 50, Part 2, JULY 2004, No. 99, pp. 78-88
LOW BIRTH-WEIGHT INFANTS AND
THE IMPORTANCE OF EARLY INTERVENTION:
ENHANCING MOTHER-INFANT INTERACTIONS
A LITERATURE REVIEW
Mokhtar Malekpour
Introduction
Approximately 7% of all babies in the
United States are born with low birth
weight (LBW) or less than 2.500 grammes
(National Center for Health Statistics,
1993).
In recent years the chances of survival
of LBW infants have increased in many
countries (Godbole et al., 1997). However,
the increasing chance of survival of premature (LBW) babies, of whom some will
be faced with developmental delay, means
that these countries will be exposed to
growing numbers of children requiring
special services, such as early intervention
strategies, in order to increase the likelihood that these children will reach their
normal developmental milestones. LBW
babies, especially very low birth weight
(VLBW) babies with less than 1.500
grammes, have a high risk of experiencing
medical complications, such as intraventricular haemorrhage (IVH) and resulting
neurosensory impairment (Blair and
Ramey, 1997).
In general, LBW infants may exhibit
much more health, neurodevelopmental,
psychological and intellectual disabilities
than normal birth weight babies.
In the last few decades, as increasing
numbers of smaller babies have survived
due to technological advances, the need to
deal with this array of medical complications has intensified1.
While there is a large amount of literature on the medical problems of
premature babies, psychological problems
have received less attention. However, research suggests that a number of
psychological difficulties are associated
with
prematurity
(Chapieski
and
Evankovich, 1997)
While medical problems are often evidenced in preterm babies at birth and
soon after, some of the psychological difficulties that arise in these children may not
be clearly seen for a number of years.
Some problems may not be identified until a child begins school at the age of five or
six, because it is at this time that more
rigid demands are placed on children
*Mokhtar Malekpour, Ph.D.
Associate Professor of Special Education, Department of Psychology, University of Isfahan,
Isfahan, Iran.
E-mail: [email protected]
* For Correspondence
79
(Leonard and Piecuch, 1997). In particular,
it is not often until school age that specific
learning disabilities are identified. According to Barsky and Siegel (1992) many
children who began life with a very low
birth weight experience problems when
they begin school. As a result, supporting
the developmental progress of LBW survivors has been one of the primary goals of
developmental science.
emotional and mental handicaps, these
babies are at risk of minor handicaps (EnsDokkum et al., 1993). In general, preterm
children display a greater prevalence of
neurological dysfunction and neuropsychological impairment.
In spite of these difficulties for LBW
babies, many studies state that newborn
babies have millions of normal neurons
(Neuberger, 1997). If these neurons are activated and used at the appropriate time,
they could compensate these difficulties to
a large extent.
Developmental difficulties
About 50% of prematurely born children weighing less than 1.500 grammes
exhibit developmental problems by preschool age (Holditch-Davis et al., 2000).
Low birth weight babies show an increase
in later developmental difficulties (Minde,
1993). Nurcombe identified the following
disabilities in these infants: specific learning disabilities, visual-motor impairments,
lower intelligence quotients, poor perceptual motor skills, speech problems, motor
problems causing them to be more clumsy
children and physical difficulties2.
Several studies have concluded that
intraventricular haemorrhage (IVH) is a
risk factor for language delays (Singer et
al., 2001). These investigators mention that
left ventricular damage in particular may
be responsible for the delay in expressive
language observed in VLBW infants at 1 to
2 years of age. Vocabulary development
and verbal reasoning in 3 year old VLBW
children have been related to the presence
and severity of IVH.
As noted before, babies with LBW often have medical problems and these may
have detrimental effects on the central
nervous
system
(Chapieski
and
Evankovich, 1997). Although, as a result of
advances in neonatal care, most preterm
babies will not develop severe physical,
80
The importance of neural plasticity and
critical periods
The brain’s plasticity, that is its ability
to change in important ways in response
to experience, presents immense opportunities. We know that there are prime times
for optimal development usually known
as critical periods or plastic periods
(Champion, 1998).
During infancy the human brain is remarkably
plastic,
largely
because
compared to other mammals it is at birth
relatively underdeveloped (Kolb and
Whishaw, 1996). The human infant is born
comparatively premature, and during the
first year of life its brain along with the rest
of its body grows rapidly. This growth is to
some extent context dependent, that
means it is influenced by environmental
factors. The concepts of critical and plastic
periods are based on the assumption that
neurological development depends on the
exposure of the brain to a predictable
timetable of developmental experience.
Siegel (1999) states that the infant’s first experiences play a major role in brain
development. Neural connections are created or strengthened depending on the
type and quality of experience. Likewise, a
lack of stimulation may lead to a slowing
down or termination of synaptic growth.
When there is a disruption of the normal
developmental timetable, as in premature
birth, neural connections are not made
properly. At the time when there are negative experiences or the absence of
appropriate stimulation, disorganisation of
brain growth is much more likely (Champion, 1998).
It has been well documented from
studies of deprivation as well as studies of
normal development, that many aspects of
perceptual, linguistic, cognitive and socialemotional development are heavily
dependent on experience. For example,
infants deprived of seeing or hearing the
world normally (e.g. those born with strabismus, those born deaf or otherwise
deprived of speech and language input)
develop vision and language problems
(Nelson and Bosquet, 2000). We know that
children reared in poverty with few cognitive challenges greatly benefit from early
enrichment. Siegel (1999) also discusses
the most important aspects of experience
in the first few years of life which is, of
course, the relationship between baby and
caregiver.
Early intervention
Early intervention practices for those
infants who are born prematurely necessarily involve the dual themes of biological
vulnerability and learning to be human
(Champion, 1998). Shonkoff (1993) puts
early intervention in this way: “Early
childhood intervention is a reflection of
our compassion for those who are vulnerable and our willingness to invest in the
best possible future for all young children.
As a science it draws support from the
knowledge-base of developmental psychology and neurobiology”.
The significant plasticity of the human
brain in the first few years of life suggests
that it is important to provide early intervention for children born prematurely. As
the brain is still forming during infancy
there is tremendous scope for constructive
modification. Infancy is a time when new
neural connections are constantly being
forged; connections which will later be
relatively static. Hence it is possible to facilitate neural development through
exposure to certain types of stimuli. While
much remains to be discovered and understood about the interaction between
brain development and early life experience, research to date indicates that
particular experiences can modify the effect of prematurity1. In a study by
McCarton et al. (1996), the Infant Health
and Developmental Program (IHDP) was
designed as a multisite randomised clinical
trial evaluating in the first 3 years of life
the efficacy of centre-based educational
intervention, home-based family support
services and paediatric follow-up in reducing cognitive, behavioural and health
problems among LBW infants. The cognitive and behavioural outcomes of the
IHDP trial at age 3 and 5 years have been
reported, as have the health outcomes at
the age of 3 years. At the age of 3 years the
children in the intervention group had significantly higher intelligence test scores
and lower scores on a parental measure of
reported behaviour problems than the
children in the follow-up only group.
Development and environment
Physical health and emotional well-being are inseparable. In addition to good
81
nutrition children need the social and
emotional contact that results from loving
relationships with others.
When children are emotionally supported by caring adults, their prospects for
learning are enhanced (Boyer, 1991). A caring environment builds emotional
maturity and social competence. Such an
environment is also consequential to cognitive and language development.
Understanding of the mutual influences between development and its
contexts is emerging from many areas of
research (McCollum, 2002). For instance,
recent brain research indicates that the
young brain is heavily influenced by different environmental influences at
particular points in its development
(Shore, 1997). Thus, whereas adequate
nutrition in the mother influences foetal
brain development, social interactions
shape the brain’s development after birth.
As babies continue to grow, development continues to be influenced by
experience. Opportunities, such as responsive caretakers, different people and
places, play, communication and social activities, will all influence how the child
develops. McCollum and Hemmeter
(1997) stress that the parent-child relationship is a particularly important
developmental context in which critical
foundations continue to be laid for all areas of development.
Intervention programmes for
LBW babies
There are many primary and secondary prevention strategies (Wolke, 1991).
Some intervention work has focused on
supporting the development of the LBW
infants while in special care in hospital
(Hospital-based programme). Some programmes emphasise support provided to
82
preterm babies and parents after their discharge from hospital and some use an
integrated approach, combining stimulation programmes in the special care baby
unit with continued support in the community (home).
Hospital-based programme
In order not only to ensure survival
but also to foster development of the LBW
and VLBW preterm babies, they are in
need of care available only in the specialised medical-technological environments
of new-born intensive care units (NICU)
and special care nurseries.
Sensory stimulation
Since the 1960s most investigations
have been done by providing preterm
babies with less or extra sensory stimulation via different sensory modalities. The
goal of these investigations has been to determine the effect of environmental
manipulations on the behaviour and development of preterm babies (Cornell and
Gottfried, 1976). Supplemental stimulation
is usually applied as soon as possible after
birth. The stimuli either try to mimic the
stimulation in the womb (i.e. heartbeat
sounds) or of the extra-uterin world (see
Field, 1980). Supplemental programmes
have focused on unimodal sensory stimulation, such as extra sensory suck
stimulation during tube-feeding or during
painful procedures (Bernbaum et al., 1983),
extra tactile stimulation provided to
preterm infants ranging from bedding on
lambskin (Scott et al., 1983), to nursing in
hammocks (Helders, 1989), baby massages
by gentle human touch provided by nursing staff and/or mothers (Jay, 1982), extra
auditory stimulation, including the plying
of mother ’s or any woman’s voice to
heartbeat (Malloy, 1979) and added vestibular stimulation by the use of extra
rocking, most frequently provided by oscillating waterbeds (e.g. Barnard and Bee,
1983).
However, there is a mismatch between
the type, intensity and patterning of the
stimulation in neonatal intensive care
units (e.g. handling, noise, light levels, social
contacts)
and
the
infant’s
developmental status. Different types of
interventions, ranging from supporting
the infant’s state (including pacifying) and
graded arousing and social stimulation,
are appropriate at different stages of the
LBW infant’s development in hospital
(Wolke, 1987).
In general, an individual care approach, educating nurses and parents on
how to contain and promote the individual infant’s behavioural organisation
(sleep - wake), appears to be the most
promising approach for direct developmental support of LBW infants in hospital.
The NICU is technically advanced, but
not enough for the baby to grow properly.
The role of environment is crucial for
brain development. The environment influences the development of the foetal
brain through the various senses of the
infant - the visual, auditory, cutaneous,
tactile, somathetic, kinesthetic, olfactory
and gustatory senses (Als, 1997). Therefore, before and after discharge from the
NICU the mother-infant bonding has to be
established and encouraged.
Mother-infant transition
programme (MITP)
mothers to interact more effectively with
their infants. This programme was designed to optimise caregiving interactions
by enhancing the mother ’s adjustment to
her low birth weight infant.
The stated aims are to enable the
mother to appreciate her infant’s specific
behavioural and temperamental characteristics; to sensitise her to the infant’s cues,
especially those that signal overload, distress and readiness for interaction; to teach
her to respond appropriately to those cues
which facilitate mutually satisfying interaction.
The MITP utilised an in-NICU 7 day
teaching programme in preparation for
discharge. After an introductory overview
of the project on day 1, the intervention
focused on one behavioural subsystem per
day and then addressed the implications
of that subsystem’s functioning for daily
caregiving and structuring of care and for
transition to going home. Each session
lasted 1 hour, and the programme was
presented as follows:
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 -
the introduction of the project
the autonomic system
the motor system
the state regulation system
the social interaction system
integration of the system for
daily care
Day 7 - preparing to go home
The sequence was followed by home
visits at 3 days postdischarge for consolidation, at 3 weeks to enhance mutual
enjoyment through play, at 1 month to assess temperamental patterns and at 3
months for review and termination of the
project (Rauh et al., 1990).
In the mother-infant transition programme Nurcome et al. 1984 teaches
83
Enhancing interactions between
mother and premature baby
The child is an active participant in the
social environment, constantly changing
this environment at the same time he or
she is being influenced by the motherchild relationship and the rest of the social
environment. The child’s development
status, therefore, is caused by the reciprocal relationship of the child and the
social-environment system. HolditchDavis et al (2000) state that mothers who
are not responsive to their children will
not provide adequate stimulation for optimal congitive maturation, and children
with developmental delays are less likely
to be satisfactory social partners.
The developmental tasks of the infant
baby provide the context for parenting.
During the first months of life an infant is
learning to regulate all body systems. He/
she is learning how to process the environment (e.g. sights, sounds, textures,
smells) as well as how to regulate reactions
to the environment. Learning to become
soothed when comforted is an important
developmental milestone (Greenspan and
Lourie, 1981).
Barnard et al. (1985) suggest that the
parent’s tasks during these early months
are to recognise and respond to the cues
the baby gives. Knowing the pattern of
nonverbal communication cues, sleep wake organisation, the way babies interact
with their environment and the meaning
of crying are all important in the first
month of life. Physical contact with the
baby, such as carrying the baby in a soft
infant carrier, promotes immediate responses to the infant’s changes in activity.
Crying behaviour is thus reduced, and the
infant’s need for responsive caregiving is
addressed.
Many studies with preterm infants
suggest that parents who can understand
84
their infant’s way of organising and communicating are much more likely to enjoy
parenting and responding to the infants in
a sensitive and growth-fostering manner.
Simple questions to parents about when
they think babies hear, see and are ready
to learn reveal that, when parents believe
babies can engage in the environment,
their behaviour toward their infants
becomes more responsive and growthenhancing (Snyder et al., 1979).
While many researchers often centre
on direct stimulation of LBW infants in
order to improve the lives of these babies,
improvement of the situation of the
caregivers is also very important.
Home visits by a nurse and occupational therapist, teaching the mother about
infant development and instructing her in
games, could lead to enhancement of interaction between mother and LBW baby.
Two clinical studies of home monitoring
and teaching programmes which commenced shortly after discharge of the
infants from hospital reported positive effects on the preterm infants’ development
(Barnard et al., 1987).
Parker et al. (1992) provided an intervention to the mothers of 26 LBW preterm
infants. The intervention of this study was
to teach mothers to observe and to contingently and appropriately respond to their
infants developmental needs. This was
accomplished by direct instruction by an
infant development specialist in weekly
meetings. Results from this study are for
the most part positive with intervention
effects for mental development and
mother-child interaction, and were obtained in comparisons with randomly
assigned LBW preterm controls.
In general, these studies showed that
integrated intervention approaches, combining sensory stimulation in the neonatal
intensive care unit with parent centred
interventions in hospital and continuing
support at home, have important effects
on LBW babies.
Conclusion
From this review it should be clear that
progress in medical technology and
neonatal intensive care is responsible for
survival of many LBW premature babies
in recent years. In addition, it is important
not only to ensure survival, but also to foster best development of this increasing
population.
Since prenatal and perinatal complication (e.g. neonatal cerebral haemorrhages)
occurring in preterm babies might constitute a potential risk to brain development,
one might expect these babies to have
more problems in the area of learning, behaviour, cognition, language, sensorymotor and neuropsychological development later in life. Therefore, these babies
will be at risk for developmental delays.
Coupled with this, premature infants are
particularly vulnerable to the effects of
psychosocial deprivation (i.e., poor
mother-child interaction).
According to Barnard et al. (1993)
preterm infants are at higher risk for developmental disabilities than are full-term
infants. An early difficulty is the poor quality of parent-child interaction. Three factors are thought to relate to this problem.
First, preterm infants are generally more
unresponsive and/or irritable. Second, parents lack the knowledge to compensate for
the infants’ lack of organisation and responsiveness and third, some parents lack
the resources or are too overwhelmed by
the preterm birth to pay close attention to
their infant’s developmental needs.
Hence, giving attention to LBW babies’ development is very crucial.
One implication of this review is the
assumption that, like most other children,
the LBW babies are more likely to benefit
from a supportive environment. Therefore, mothers may need nursing support
to maintain a high level of positive interaction with the baby and to provide appropriate stimulation to foster sensory-motor,
language, social, emotional and behaviour
growth. Early intervention programmes
seem to be advisable for these mothers
and their babies. Intervention programmes for LBW babies typically provide
a supplemental stimulation for the
neonate. Teaching the mother exercises
and age-appropriate stimulation to facilitate development of premature babies
have been proven to be effective.
Footnotes
1
2
Thakker, J. (2000). Premature babies. The importance of early intervention. Prepared for the
Champion Center, Psychology Department,
University of Canterbury, Christchurch, New
Zealand.
Nurcombe, B. (1998). An intervention program
for the mothers of low-birthweight babies - a nine
year follow-up. Paper presented at the 5th
Annual Meeting. The Australian Association
for Mental Health, Sydney.
Summary
Although low birth weight (LBW) babies are not an homogeneous group and
therefore not at an equal risk for developmental delays, research evidence shows
that they are vulnerable to medical complications, such as neurological dysfunction and other neurodevelopmental
problems. In addition, by school age LBW
85
children are at increased risk of having
learning and behavioural problems.
Therefore, to prevent medical complications and later developmental delays,
LBW babies might need intensive care in
order to compensate medical problems
along with proper stimulation (e.g. sensory stimulation) during hospitalisation.
Soon after discharge from the newborn
intensive care unit, stimulation of the baby
has to be started. To do this, we have to
improve and enhance the mother-baby interactions.
The purpose of this article is to describe
the LBW babies’ problems and to highlight
the importance of mother-baby interactions so that LBW babies can achieve their
potential.
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