Early
Contact
and
Maternal-Infant
Bonding:
One
Decade
Later
Michael E. Lamb, PhD
From the Department of Pediatrics, University of Utah Medical School, Salt Lake City
ABSTRACT. In the last decade, there has been
consid-erable speculation concerning the importance of early skin-to-skin contact between partunent mothers and neo-nates. This contact is viewed as crucial to the occurrence of maternal bonding, which is seen as a precursor of optimal maternal behavior and thus as a necessary ante-cedent of optimal child development. In the present re-view, these conclusions are shown to have been based on
equivocal findings obtained in methodologically
impov-erished studies. Although early contact may have modest but beneficial short-term effects in some circumstances, no positive long-term effects have been demonstrated.
Pediatrics 70:763-768, 1982; bonding, attachment, early
contact, maternal behavior.
In the last decade, considerable excitement has
been generated by the suggestion that events
oc-cutTing in the immediate postpartum period could
have a substantial influence on parental behavior
and thus on subsequent child development. Klaus
and co-workers’ and de Chateau57 have argued
that there exists in human mothers a sensitive
period immediately after delivery during which
cer-tam experiences are more likely to produce
affec-tionate attachments or bonds to infants than at any
other time. When this “bonding” process is
inter-rupted, warned Klaus and Kennell,’ various forms
of aberrant parental behavior, including child abuse
and neglect, are more apt to occur and suboptimal
child development is more likely. Such claims
pro-vided the scientific basis for changes in accepted
obstetric procedures, and we owe a great deal to Klaus and Kennell for facilitating the humanization
of birthing practices. It is important, however, to
evaluate the evidence upon which their argument
was based, because their conclusions have
far-reaching implications for understanding the
deter-Received for publication May 7, 1982; accepted June 16, 1982. Reprint requests to (MEL.) Department of Pediatrics, Univer-sity of Utah Medical School, Salt Lake City, UT 84132. PEDIATRICS (ISSN 0031 4005). Copyright © 1982 by the American Academy of Pediatrics.
minants of human behavior and development. That
is the goal of this paper. For brevity, I will not
discuss either (1) the determinants of maternal behavior in other species, although I have argued
elsewhere8 that the analogy drawn by Klaus and
Kennell is flawed in many respects, or (2) research
on early contact with preterm infants, inasmuch as
these studies involved contact after the
hypothe-sized sensitive period. Readers are referred to a
longer review8 for fuller details, especially those
concerning the manner in which mothers in the
various groups were treated. Unless
otherwise
noted, control group mothers were denied contact
with their nude infants.
SHORT-TERM CONSEQUENCES OF EARLY
AND EXTENDED CONTACT
In the first study, Klaus et al2 allowed a group of
14 poor, predominantly black, unmarried,
primip-aras one hour of contact with their nude newborns
during the first
three
hours after delivery. Thesemothers were also given their babies for five
addi-tional hours on each of the next three days. One
month after delivery, the mothers who had been
allowed
extended
contact were reportedly morere-luctant to leave their infants with baby-sitters, more
attentive during a pediatric examination, soothed
their
babies more, and engaged in more fondlingand “en face” behavior than did mothers in the
control group. These fmdings provide very little
support for claims regarding the beneficial effects
of early contact for several reasons. First, only a
small proportion of the measures (five out of at
least 75) revealed significant differences, so most
may have occurred by chance. Thus we can only
consider the findings reliable if they can be
repli-cated by other researchers. Second, early contact
was confounded with extended contact. Third, the
nursing and medical staff members (including the
physician who conducted the pediatric
contact group were special, and they are likely to
have been treated differently as a result.
In a later study conducted in Guatemala, the
same researchers compared three groups: mothers
receiving routine care (first contact with clothed
baby at 12 hours); mothers who had 45 minutes of
skin-to-skin contact 12 hours post partum; and
mothers who had 45 minutes of skin-to-skin contact immediately after birth.9”#{176} Thirty-six hours after
delivery, mothers who had early contact engaged in
more en face behavior (and thus seemed more
af-fectionate) than mothers in the control groups.
Although only one of the 19 behavioral measures revealed a significant difference, the specific
differ-ence reported replicates the finding reported by
Klaus et al2 and this makes the finding more
im-pressive.
In another series of studies, de Chateau and
Wiberg5”’3 allowed 22 middle-class Swedish
pri-miparas and their infants 15 minutes of extra
skin-to-skin contact shortly after delivery during which
a midwife helped the mothers establish nursing.
These women were then compared with 20
primip-aras who experienced routine treatment which
in-volved no skin-to-skin contact. Thirty-six hours
after delivery, the groups differed on three of 35
measures (mother sitting up, leaning on elbow, and
holding infant) all three of which were measures on
which Hales et al’#{176}found no group differences.
These differences do not indicate that the mothers
who experienced early contact were more closely
bonded, more competent, or more affectionate, and
they were found only among the mothers of boys.
Furthermore, the babies in the control group cried
a great deal more during the observation, leading
one to wonder whether group differences were
at-tributable to differences in the infants’ behavior. In
sum, the effects revealed in this study were of
modest magnitude, unrelated to maternal
attach-ment, and failed to replicate findings obtained in
other studies.
Three research teams have attempted to
distin-guish between the effects of early and extended
contact. First, Hopkins and Vietze’4”5 assigned 104
lower income primiparas and their newborns to one
of four treatment conditions: early contact;
ex-tended contact (rooming-in); both early contact and
rooming-in; and routine care. Some group
differ-ences were evident in observations two days after
delivery, but there were no differences in
affection-ate behavior. The number of significant group
dif-ferences also seems to have been less than would
be expected to occur by chance. Second, Grossman
et al’6 compared the behavior of primiparous
Ger-man mothers in four similar groups. Mothers in the
early contact groups showed more tender touching
and cuddling on days 2 or 3 and 4 or 5 than did
mothers in the extended contact and control groups.
However, these differences were only observed in
mothers who had planned the pregnancy, and there
were no group differences seven to nine days post
partum. At no point did extended contact appear to
have a significant effect. Third, Carlsson et al’7”8
and Hwang’9 observed Swedish primiparas from
diverse socioeconomic backgrounds breast-feeding
their infants on the second and fourth days after
delivery. Some of the mothers had been allowed to
keep their naked infants for one to two hours
im-mediately after delivery, whereas others
experi-enced the regular hospital routine. Whether or not
they were allowed extended contact, mothers who
experienced early contact showed more contact (ie,
behaviors involving physical contact) and fewer
noncontact behaviors during both observations. No
significant group differences emerged on those
mea-sures (eg, en face, touching) on which other
re-searchers have found significant differences. Thus
we have a specific failure to replicate, but some
support for the value of early contact. These three
studies thus suggest that early (although not
ex-tended) contact has a short-lived beneficial effect
on some mothers. Other studies, however, fail to
substantiate this.
Taylor et al2#{176}observed two groups of middle-class
mothers who were allowed different amounts of
exposure to their infants after delivery. There were
no differences between the groups at two and 30
days post partum on measures of: the amount of
time mother and infant spent together; reported
maternal attachment; the mothers’ perceptions of
their infants; maternal behavior during feedings at
2 and 30 days of age; maternal sensitivity to infant
needs; and reluctance to leave the infants with
baby-sitters. Mothers and sons (but not daughters)
who had early contact were rated higher on “quality
of interaction.” Unfortunately, this study provides
only a weak test of the hypothesis of Klaus and
Kermell because: (1) the mothers in both groups
had some early contact; (2) the extra contact in the
early contact group only began 30 minutes post
partum; and (3) skin-to-skin contact was not
pro-vided because the infants were clothed.
In another recent study, Svejda et al2’ observed
30 middle-class primiparas and their infants 36
hours after delivery. Half of the mothers and infants
experienced roughly the same contact as those in
the study group of de Chateau.5 When observed
interacting with and breast-feeding their infants 36
hours after delivery, however, mothers given extra
contact and routine hospital care did not differ on
any of 28 specific measures or four composite
mea-sures, which included most of the variables used in
previous studies of infant-mother bonding.2”#{176}”
Curry,22 albeit in a small study involving only 11
control mothers and nine study mothers allowed at
least 15 minutes of contact with their naked infants
within the first hour. These conditions were similar
to those in the study of de Chateau and Wiberg,”
but there were no differences between the two
groups of mothers at 36 hours on any of the
mea-sures used by de Chateau and Wiberg.
Finally, Anisfeld and Lipper3 compared mothers
allowed one hour of contact at delivery with
moth-ers accorded the normal hospital routine. During a
feeding two days later, mothers who experienced
early contact were more affectionate. However,
they also reported receiving more social support,
which suggests that the groups may not have been
comparable initially.
LONG-TERM CONSEQUENCES OF EARLY AND
EXTENDED CONTACT
On the assumption that short-term effects were
well established, many researchers have attempted
to discern long-term effects. In a one-year
follow-up of their subjects, Kennel! et al24 reported that
mothers who had been allowed early contact with
their infants appeared more concerned and
atten-tive during a pediatric examination than did
moth-ers in the control group. The mothers who
experi-enced early contact also reported being more
anx-jous and more reluctant to leave their infants with
baby-sitters. On an unknown but apparently exten-sive number of behavioral measures scored during
free play, picture-taking, interview, and Bayley test
sessions, however, mothers in the two groups did
not differ. In all, therefore, the vast majority of the
measures revealed no group differences. It is
im-pressive, however, that the attitudinal differences
evident at one month post partum stifi
distin-guished the groups at one year.
Five of the mothers in each group returned for
assessments of maternal speech patterns when the
children were aged 1 and 2 years.25 At one year post
partum, the control group mothers used more
state-ments. A year later, the mothers in the study group
asked more questions, and used more words per
proposition, fewer content words, more adjectives,
and fewer commands in addressing their children
than did the mothers in the control group. Given
the sample size, these must be considered as pilot
data, rather than serious experimental evidence.
The findings, in any event, only show that the
speech patterns differed, not that they were better
or worse.
At 5 years of age, 19 of the 28 children took three
tests of intellectual and linguistic functioning.26’27 In
the study group, a few measures of maternal speech
were significantly correlated with measures of the
child’s linguistic competence, whereas these
corre-lations were not significant in the control group.27
Because the ratio of significant differences to the
number of statistical tests was low (7: 140) there
was, at best, weak support for the claim that
ma-ternal characteristics were associated with the
child’s competence only when mother and infant
experienced early contact. However, the
associa-tions between maternal and child measures did not
involve facilitation of the children’s development,
as there were no group differences in performance
on any test.
In their follow-up, de Chateau and Wiberg’2
found that the early contact mothers kissed and
held their 3-month-old infants more in the en face
position and cleaned their infants less than did
mothers in the control group. In addition, infants in
the early contact group cried less and smiled!
laughed more than infants in the control group. Of
61 measures, only these five revealed significant
group differences. Once again the effects were
strongest for mothers and sons, and the
interpre-tation is again unclear: Could differences in infant
behavior during the observations have accounted
for the differences in maternal behavior? Did early
contact create happier dyads? Or were the infants
in the control group temperamentally more irritable
(remember that they cried more at both 36 hours
and 3 months of age) and thus produced differences
in maternal behavior? In any event, Curry22 was
unable to replicate these findings in an otherwise
comparable study.
One year post partum, the early contact mothers
studied by de Chateau and Wiberg28 held their
infants closely more often, engaged in more
non-functional touching, and talked more warmly than
did the control group mothers. On standardized
tests, the children who had received early contact
were not significantly more advanced
developmen-tally at 1 or 3 years of age.7’29’3#{176}Compared with
control mothers, early contact mothers also
re-ported more accelerated language development, less
eagerness to return to work, less paternal
involve-ment, less willingness to give infants rooms of their
own, and earlier bladder training. The meaning of
these differences is unclear. Further, it seems that
only a chance number of the many items assessed
revealed significant group differences. In their
fol-low-up, Carisson and colleagues’7’3’ found that the
effects of early contact evident two and four days
post partum disappeared by the time the infants
were 6 weeks old.
Au and Lowry32 studied 100 lower-class Jamaican
women, half of whom had 45 minutes of contact
immediately after birth, whereas the others first
experienced contact nine hours post partum.
Moth-ers were observed during clinic examinations when
weeks, there were no group differences in maternal
behavior, whereas at age 12 weeks, mothers in the
study group were more likely to stand and watch
the examination, more likely to look at their infants
while feeding them, and more likely to vocalize to
them. These differences may suggest that mothers
in the early contact group felt more comfortable
with the examining physician; she or he was not
blind to experimental condition and may well have
behaved differently toward mothers in the two
groups. Inasmuch as the differences were not
evi-dent at six weeks post partum, furthermore, it seems
unreasonable to attribute them to differences in
early contact. There were no group differences in
the mothers’ reported willingness to leave their
infants with baby-sitters or in the likelihood of
breast-feeding, but the early contact mothers were
less likely to use supplementary foods. Overall, it
seems that the four significant group differences
were derived from 150 comparisons, which is less
than would be expected by chance.
In one of the largest attempts to assess the effects
of both early and extended contact, Siegel et al
studied 321 women, most of whom were black and
unmarried. At both four and 12 months post
par-tum, observations and interviews yielded 30 specific
behavioral items and 92 ratings which were then
factor analyzed. At four months, early and extended
contact accounted for only 2.8% of the variance in
“maternal acceptance” and 3.3% of the variance in
“consoling.” At 12 months post partum, early and
extended contact accounted for only 3.2% of the
variance in “infant positive/negative behavior.”
Early and extended contact did not affect the
like-lihood of reported abuse or the utilization of health
care services. Contact thus appeared to have a
trivial effect on maternal behavior.
By contrast, O’Connor reported that, by 17
months, more routine care mothers provided
sub-optimal care than mothers who had roomed with
their infants. The low incidence of child abuse
makes the finding difficult to evaluate, however,
especially as it was not replicated by Siegel et al.
In several later assessments of the subjects of
Hopkins and Vietze’5 no differences in affectionate
behaviors were reported.36’37 Group differences,
when found, were not consistent from assessment
to assessment and an insignificant number of the
many (>100) measures revealed group differences.
Again, extended contact in the lying-in period did
not have long-term effects.
Anisfeld and Lipper23 observed and interviewed
their subjects again three months after delivery.
They found that the early contact mothers reported
being less eager to place their babies on schedules
and more likely to pick up their babies when they
cried. Taylor et al,20’37’ however, found that early
contact had no effect on maternal perceptions of
infant temperament at age 8 months and had no
effect on the security of attachment at age 12
months. Similarly, in their follow-up, Grossman et
al39 found that early contact had no effect on the
security of attachment. Rode et a14#{176}likewise found
that mother-infant separations had no effect on the
security of attachment among preterm infants.
By contrast, Kontos4’ reported that, when
ob-served in free play at home when the infants were
1 and 3 months old, middle-class mothers who had
early contact scored much higher on a composite
“maternal attachment” index at both ages than did
mothers in a routine care comparison group.
Unfor-tunately, all observations were conducted by the
author, who was aware of the hypotheses and of the
mothers’ group status. The potential for bias was
thus great.
Instead of the quality of mother-infant
interac-tion, several researchers have examined the effects
of early contact on breast-feeding. Sosa et al42
con-ducted three such studies involving primiparous
Guatemalan women. In all three, mothers in the
experimental group nursed their nude babies on the
delivery table for 45 minutes before a 12- to 24-hour separation. In the first study, mothers in the control
group continued breast-feeding significantly longer;
in the second study, the mothers in the study group
breast-fed nonsignificantly longer. Unfortunately,
the mothers in the control and study groups came
from different socioeconomic backgrounds. In the
third, smaller, study, the early contact mothers
breast-fed significantiy longer than mothers in the
control group. Only 25% of the mothers in the
control group v.’ere still breast-feeding at five
months post partum, however, whereas a larger
survey revealed that 50% usually continued
breast-feeding this long. Less than 60% of the study group
mothers continued breast-feeding five months,
which suggests that, relative to the common
cul-tural practices, early contact had, at best, a modest
effect on breast-feeding.
In Brazil, meanwhile, Sousa et al4t reported that
mothers who were allowed to suckle their infants
right after delivery and then “roomed-in” with their
infants were much more likely to continue
breast-feeding for at least two months (77%) than were
mothers accorded the normal hospital routine
(28%). These results are compromised, however,
inasmuch as a “friendly nurse” encouraged and
provided advice about breast-feeding to the
moth-ers in the early contact group but not to those in
the control group.
Several other studies have explored the effect of
early contact on breast-feeding. Johnson44 reported
that mothers who nursed during the first hour were
partum than were mothers who first breast-fed (and
handled) their infants at 16 hours of age. However,
Carisson et al,3’ Vietze et al,36 and Taylor et al#{176}
reported no effects on breast-feeding. De Chateau
and co-workers7’29’45 reported that early contact
pro-longed breast-feeding, but unfortunately there were
prenatal group differences in attitudes toward
par-enting, and the early contact mothers were assisted
in breast-feeding.
SUMMARY
The preponderance of the evidence thus suggests
that extended contact has no clear effects on
ma-ternal behavior. By contrast, some researchers seem
to have shown that early contact has positive
short-term effects. This conclusion appears premature,
however, as serious methodologic problems
com-promise the research. First, there is the problem of
nonreplication. Even though many studies report
positive consequences, they usually fail to find
ef-fects on similar measures, even when the same
subjects are followed over time. Otherwise
compa-rable studies often fail to demonstrate similar
ef-fects.
Second, some of the behavioral differences
ob-served appear unrelated to maternal attachment.
For example, de Chateau and Wiberg” in their early
(36 hour) assessments only found differences on
measures of maternal posture that bear no
relation-ship to maternal attachment.
Third, many of the researchers have employed
multiple measures and observed statistically
signif-icant differences on a small proportion of these:
generally, the number of significant group
differ-ences usually hovers around the number that would
be expected to occur by chance.
Fourth, many of the studies concerned with
ef-fects on breast-feeding are confounded by
encour-agement or coaching for mothers in the study group.
Other studies report no effects. Even if effects were
found, they would not demonstrate that early
con-tact affects maternal attachment, for although
breast-feeding may facilitate bonding, it is not an
index thereof.46
Fifth, it is not clear that any effects observed are
accounted for by early contact rather than
differ-ences in treatment by medical and nursing staff
who know that the study group subjects are special.
Finally, preexisting group differences, as in the
Guatemalan sample of Sosa et al42 or the Swedish
sample of de Chateau,7 seem as likely as the
treat-ment itself to account for the reported “treatment
effects.”
In sum, claims regarding the effects of early
con-tact on maternal-infant bonding are not well
sup-ported by the empirical evidence. Early contact has
no enduring effects on maternal attachment, but
may sometimes have modest short-term effects on
some mothers in some circumstances.
Unfortu-nately, we do not know what these characteristics
might be, as the evidence is inconsistent or lacking.
There is no support for the claim47 that early
con-tact is especially beneficial for young, poor, socially isolated mothers.
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