T H E J O U R N A L OF

PEDIATRIC S JULY

1977

V o l u m e 91

Number

1

M E D I C A L PROGRESS

The mother-newborn relationship: Limits of adaptability Betsy Lozoff, M.D.,* Gary M. Brittenham, M.D., Mary Anne Trause, Ph.D., John H. Kennell, M.D., and Marshall H. Klaus, M.D., Cleveland, Ohio

THE WIDESPREAD DISTURBANCE in parenting and the fragmentation of families in the United States suggest the need for re-examination of those medical practices that affect the involvement of parents with their children. Throughout most of human history, anatomic, physiologic, and behavioral adaptations within the motherinfant relationship have been capable of providing the nutrition, protection, and social stimulation necessary for the infant's survival and development. Perinatal medical care was introduced in this century with the purpose of further decreasing mortality and morbidity by preventing infection and managing physical problems. There is now a growing body Of evidence that these advances inadvertently alter the initiation of the mother-infant relationship and that some mother-infant pairs may be strained beyond limits of their adaptability. Maternity hospital routines were established before recent research in pediatrics, anthropology, developmental psychology, ethology, and physiology created a new appreciation of the From the Rainbow Babies and Childrens Hospital, Case Western Reserve University School of Medicine. Supported in part by grants from the Rockefeller Foundation, the Grant Foundation, and Maternal and ChiM Health Grant No. MC-R-39033Z *Reprint address: Division of Geographic Medicine, 233 Wearn Building, UniversityHospitals, Cleveland, OH 44106.

remarkable capacities of the neonate for social interaction and of the importance of the newborn period for a mutual parent-infant involvement: Examining this literature at a time of increased awareness of family disturbance may help evaluate our care of the healthy newborn infant and provide a scientific basis for formulating maternity hospital policy that will foster positive early parent-infant involvement as well as prevent some physical complications of childbirth. SOCIAL INTERACTION Infants die or develop with difficulty if given only food, warmth, and protection. The work of Spitz, 1 Bowlby,'-' and others :~ with institutionalized infants emphasizes that babies need intimate involvement with other human beings for their immediate survival as well as for their long-term emotional health. Recent research indicates that organized patterns of behavior in both neonates and caregivers have evolved to help ensure that this requirement is met. Scientific appreciation of the neonate's remarkable and appealing capacities for social interaction is new?' ~ The transformation in our perception of the neonate, from that of a simple reflexive organism to a complex responsive being, depended upon the recognition of different states o f infant arousal. 6. 9 Wolff6 identified six such Vol. 91, No. 1, pp. 1-12

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Lozoffet al.

states: quiet sleep, active sleep, drowsiness, quiet alertness, active alertness, and crying. Examining newborn infants in their brief and transient periods of alertness 1~ and looking for their optimal responses 11have shown that infant behavioral organization contributes to social exchange. Adults seem to have a responsiveness complementary to these neonatal capacities. Research on this general readiness of neonates and adults for interaction must be understood before discussing the development of specific involvement between mothers and their babies. GENERAL READINESS OF NEONATES AND ADULTS FOR INTERACTION The following experimental studies demonstrate that newborn infants, with their relatively sophisticated sensory systems, respond Preferentially to stimuli that occur in human social interaction. Proprioception. A crying neonate becomes quiet and visually alert when lifted to the caregiver's shoulder. 1~ This movement temporarily soothes even a hungry infant, arouses the sleepy one, and increases visual attentiveness in the already alert baby. Proprioceptive-vestibular stimulation must contribute to these changes in state, because neither physical contact nor merely being upright has the same effect? :~ Since the everyday actions of rocking, carrying, and picking up babies include proprioceptiveVestibular stimulation and thus encourage neonatal alertness, a readiness for interaction between caregiver and neonate is created. Vision. Despite statements to the contrary in some pediatric texts, at birth the neonate can see, focus, follow, and exhibit visual preferences? a, 1.... Furthermore, recent but controversiaP ~evidence suggests that newborn infants are especially interested in facelike configurations. Within minutes after birth, babies visually follow a facelike pattern more than others of similar brightness, complexity, and symmetry? 6 Neonates can also interact with adults by imitating visually presented behaviors. When naive observers rate videotapes of two-week-old infants who were watching an experimenter protrude his lip, stick out his tongue, open his mouth, or move his fingers, they correctly match infant movements with those of the unseen experimenter, lr Adults thus perceive the neonatal behaviors as imitations, though approximate and gross. This amazing visual-motor coordination may fade, as may other precocious neonatal responses such as reaching and walking. 1~Imitation reappears slowly and reaches similar sophistication only toward the end of the first year. TM These neonatal visual capacities are important for the origin of social relationships because adults are interested in making eye contact with babies and are attracted by infants' visual following. -~176 '-'1

The Journal of Pediatrics July 1977

Hearing. Newborn auditory and motor systems are also organized for responsive interaction. The neonate attends to the frequencies of speech and to speech sound patterns more than to other frequencies or pure tones. 2~ One- to two-day-old babies in the active alert state move rhythmically and synchronously with the articulated structure of adult speech (English or Chinese), but not with mechanical tapping noises or with the human voice making disconnected vowel sounds. 23 This ability may be important i n acquisition of language and analogous to the responsive body movements in face-to-face conversations. Thus, infants have the capacity to interact nonverbally with the speaking voice of caregivers even from birth; this responsiveness may encourage parental verbal interaction. Crying. The newborn infant not only responds to adult behavior but can also initiate interaction. As every parent knows, Crying is compeliingly effective in making caregivers come close, stay close, and attend to infant needs. '-'~ The neonate has a range of cries that are spectrographically distinct and audibly different. 2~ ~ WollT-'6 has distinguished four types: the cries of hunger, anger, frustration, and pain. Although caregivers may discriminate between cry types, 27' ~8 only the pain cry produces a characteristic response. When out of sight of their babies, mothers in the United States often do not react immediately to a taperecorded rhythmical hunger cry. Upon hearing their infant's tape-recorded paincry, however, mothers typically rush into the room, are relieved to find their babies safe, but not amused by the investigator's trick. '-'"Among Kalahari hunter-gatherers in Africa, the infant's hunger cry receives attention only from the mother, but a pain cry produces an orienting response from all the adults in the village and immediate approach from a dozen? ~ The characteristics of the pain cry seem to elicit stereotyped adult behavior which ensures that the crying infant in danger will get help. Because the adult intervention of picking up the infant is likely to induce soothing and visual alerting, the infant's initiating effort thus brings social exchange as well as protection and provision for physical need. Adult responsiveness. The neonate's readiness for social interaction has been described in some detail because the infant's contribution has been woefully underestimated until recently. As a result of intensive study, neonatal capacities are now understood better than those of adults. Although little empirical research has focused on adult readiness to interact with infants, some behaviors have been described. Most adults want to "do something" about a crying baby. -~'They perceive the infant's presocial smile, eye contact, and reflexes such as the grasp as interactive indications of recognition, affection, or appre-

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The mother-newborn relationship

ciation. :'~':" Although parents may consider their own infant especially beautiful and wonderful, both men and women in general are attracted to the "babyness" of infant physical appearance:"-': the high bulbous forehead, round protruding cheeks, and relatively large head and eyes? :~ DEVELOPING A SPECIFIC NEONATE RELATIONSHIP

MOTHER-

The readiness of the neonate and the adult for mutual involvement encourages social stimulation, protection from pain or danger, and satisfaction of physical need. The survival value of these capacities suggests that they are the product of evolutionary selection. :'4 Bowlby :'' first postulated that a specific attachment between infant and mother also functioned to increase infant survival during the long history of the human species. Many studies have since focused on the older infant's tie to its mother? '~-,~''but only recently have investigators turned to the initiation of the relationship in the neonatal period. Since mothers are the primary caregivers for most infants, research on the early development of social relationships has focused on mother-infant interaction. Description of the fatherneonate relationship awaits further study.:" " '~ Specific responses quickly develop between neonate and mother if given the experience of repeated contact. Neonates soon recognize and prefer their own mothers. Although infants are exposed to the mother's transmitted voice in utero, a specific response is absent at birth. However, newborn infants do respond more to the female than to the male voice ~a- 44 and will rapidly develop a preference for the mother's voice through her caregiving and interaction?:' Newborn infants recognize the mother's smell. Babies do not discriminate at two days, but selectively turn their heads to their own mother's dry breast pad at six to ten days of life? ~ Neonates may be upset by unusual maternal appearance or behavior. When bottlefed by their mothers wearing a mask, one-week-old infants become distressed, avoid their mothers physically and visually, feed poorly, and have disruptions in their sleep cycle? ~ Thus, through both preference and avoidance behaviors infants indicate recognition of the mother's familiar presence, odor, appearance, and behavior?S. ~,, The infant more readily organizes his cycles of sleeping, waking, and c u i n g if exposed to a single caregiver in the first ten days of life. Newborn infants who room-in cry distinctly less and establish a day-night rhythm more quickly than infants in a traditional nursery with multiple caregivers and four-hour feeding schedules. :'~ Thus, the baby a mother takes home may be different depending on its experience with rooming-in or with nursery care. The

3

difference in amount of crying probably relates to the delay in response in the nursery. If the caregiver intervenes within 90 seconds of the start of a crying episode, newborn infants stop crying in less than five seconds. If the caregiver waits more than 11/2 minutes to respond, neonates take much longer to soothe and require an average of 50 seconds of attention before quieting? 1 Among rooming-in infants such qualitative differences in caregiver behavior do affect infant crying, sleep duration, and visual regard?'-' The specificity of the mother's social response also develops through rooming-in. A mother recognizes her own infant's cry by 48 hours, even when sharing the room with other mothers, and by the second night, awakens only to its cry? ,' Rooming-in affects the life of the pediatrician or nurse practitioner as well, since the mother who rooms-in with her baby feels more selfconfident ~' and makes fewer calls for advice from medical personnel during the first week at home? ~ True interaction requires that reactions between partners be perceived as contingent-that each recognizes the behavior of the other as a response to its own behavior? ~ Since an infant's ability to recognize a connection between his signals and maternal reactions is limited, it is the mother who makes responsive interaction possible by modifying her behavior to compensate for the restrictions in the infant's capacities. Mothers respond to the neonate's transient states of alertness with affectionlooking en face, smiling, talking, humming, singing, cuddling, and kissing? ~ Over the next few months these exchanges develop into interactive play episodes in which mothers use extremely slow and exaggerated speech patterns, facial expressions, and body movements, apparently in adaptation to the young infant's perceptual capacities. :''~" Although such face-to-face encounters provide the opportunity for synchrony in the motherinfant relationship, cultures vary greatly in their emphasis on this kind of interaction. People in the United States seem to rely on face-to-face exchanges with infants more than in other societies, many of which emphasize reciprocal bodily interactions. '~...... Perhaps for this reason so much neonatal research in the United States has focused on vision and hearing, the distal senses, and so little has detailed bodily interaction. To summarize, the neonate's organization of sleepwake cycles is facilitated by continuous exposure to a single caregiver in the first ten days of life. Within the first week, the newborn infant shows preferences for the mother's smell, voice, and familiar appearance. These preferences as well as the neonates soothing when picked up and held may contribute to a sense of maternal reward. The infant responds to proprioceptive-vestibular stimulation by ceasing to cry and becoming alert. In the alert

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The Journal of Pediatrics July 1977

Table I. Mammalian care patterns and breast milk composition*

Example of species (number of species studied) Deer Oo~looo,,I,,~an (n = 13) (n -- 18) (n = 22) beings Infant care pattern

Nest or cache

Nest or cache

Feeding interval

5-15 hr

2-4 hr

Carry, follow, hibernate Contin-

??? ???

UOUS

Mean % breast milk component Protein Fat Carbohydrate Water

10:5 16.5 3.0 67.0

9.6 9.4 3.3 76.3

3.9 4.5 5.1 86.9

1.2 3.8 7.0 87.6

*The mean percent of each breast milk component in species which hibernate, carry, or follow is significantly different (p < 0.01) from the corresponding value in species which nest or cache their young, even those which feed as frequently as every 2 to 4 hours. Calculations derived from Ben Shaul) 8

states, the neonate particularly prefers faces, responds imitatively to adult gestures, and moves in synchrony with the sound of human language. Adults find the physical appearance of babies appealing, interpret neonatal behaviors as interactive, and react to the infant in distress. Mothers are able to modify their behavior to match the fimits of infant responsiveness. A mother may soon recognize her own baby's cry and, by intervening promptly, help the infant quiet quickly and associate its signal with maternal response. Under appropriate conditions, these maternal and neonatal capacities for interaction may be integrated into a synchronous relationship through mutual adaptations during the first weeks of life. PATTERNS

OF INFANT

CARE

The capacities of mothers and newborn infants for social interaction evolved over many centuries when infant care practices were vastly different from those of contemporary industrialized societies. In attempting to improve the physical health of mother and infant, perinatal medical management has unwittingly interfered with the beginnings of their mutual involvement. Current research suggests that these practices approach limits beyond which breast-feeding may fail and maternal involvement may be impaired. To understand the effects of hospital policy on a mother's ability to meet her infant's needs, we must first consider the adaptive significance of past patterns of infant care. In our species' history of more than a million years,

breast-feeding has been an invariable feature of infant care. Until this century an infant was unlikely to survive without a lactating woman. Through the long process of evolution elaborate anatomic, physiologic, and behavioral adaptations for breast-feeding have developed in both the mother and infant. Almost all mammalian mothers have nipples, but only human beings have protuberant breasts. Although their function is unknown, hypotheses have emphasized the importance of prominent breasts in enhancing social exchange, ~~suggesting that they permit mother-infant eye-to-eye contact or allow the infant to scan the mother's face during nursing. The infant's rooting reflex brings the nipple into its mouth; the contact of the nipple against the palate and posterior tongue elicits suckling or "milking," and the buccal fat pads help keep the nipple in place. Suckling triggers maternal prolactin and oxytocin release. Prolactin stimulates milk synthesis and oxytocin produces milk release (the "letdown" reflex). ~I~~2The amount and frequency of suckling determines the amount of breast milk produced, and without suckling, milk production ceases. '3 In the lactating woman, an infant's cry stimulates blood flow to the areolar area and dripping of milk from the breast2' As the infant empties the breast during each feeding, the fat content of the milk increases and the water content decreases. The associated changes in taste and texture, obviously absent in infant formulas, may be factors in the infant's decrease in appetite and suckling and termination of the nursing episode. 75 The antibodies, ~". 7~lysozymes, TM lymphocytes and macrophages, ~9 and other components 8~ of colostrum and transitional breast milk defend the neonate against infection. 81-s~ Thus, breast milk provides more than nutrition; breast milk also furnishes protection from infection, which may b e c o n s i d e r e d the major human "predator" during evolution. Breast feeding identifies human beings as mammalsY ~ Among terrestrial mammals, infant care patterns are correlated with the composition of breast milk. 87. "~ In species which nest or cache their infants, breast milk is high in protein and fat, mother-infant contact is intermittent, and feedings are spaced two to 15 hours apart. ~8 Thus, these infants are adapted for separations by receiving their total nutritional requirements in brief contacts with the mother. By contrast, species in which infants are carried by, hibernate with, or follow their mothers have tow-protein-low-fat breast milk, constant mother-infant contact, and essentially continuous feeding. ~8 Significant differences in breast milk composition persist even if the continuous feeding species are compared with those species which nest or cache the young and feed as frequently as every two to four hours (Table I). Human milk is low in fat and extremely low in

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protein. Since human babies cannot follow their mothers at birth, comparative physiology identifies the human pattern of infant care as that of carrying and continuous feeding, s7 The history of human infant care demonstrates that in fact babies were probably carried and nursed frequently for over 99% of the species' existence?" During this period of more than a million years, human beings lived as hunters and gatherers) ~ 94 Societies depending on this mode of subsistence are comprised of small, mobile groups?: Food gathering, typically by women, supplies 40 to 60% of the total diet in over two-thirds of hunting and gathering societies.9~ ',~ Among contemporary huntergatherers of the warmer climates in which human beings evolved, ~ babies are nursed frequently and carried during the women's daily foraging excursions. While being carried, the infant interacts with its mother, experiences abundant physical and vestibular stimulation, and observes the activities necessary for later independent functioning. '-'~~ Thus, through most of human history, the mother-infant relationship provided infant nutrition, temperature regulation, protection, early education, and social stimulation. In present-day industrialized societies the needs of infants can be met outside the mother-infant relationship. The pattern of carrying that endured for at least a million years has been replaced by one that more closely resembles nesting or caching. Infants spend little time in physical contact with caregivers, '~, '~ lie horizontally out of sight for many hours of the day, and are fed at two to four hourly intervals. Nutritional needs can be met by breast milk substitutes, and bottle-feeding does not generally allow as much infant control, self-regulation, and synchronized interaction as breast-feedingY ~ '~ The infant's temperature can be maintained by clothing and heating, protection provided by housing, cribs, playpens, highchairs, and gates, and social stimulation supplied by any responsive caregiver. The economic contribution of women now conflicts with child care and requires separation of mother and infantY ~ Although infants have survived these remarkable transformations of care for a few generations, the evolutionary impact on normal infant development and normal maternal involvement is unknown. There is now clear evidence, however, that certain maternity hospital practices interfere with breast-feeding and early maternal affection. The routine postpartum separation of healthy mothers and infants appears to approach the limit of minimal contact below which disruptions occur for some mothers. For the mother and infant with a problem (prematurity, malformation, inexperience, emotional disturbance, social isolation), the

The mother-newborn relationship

5

relationship is even more susceptible to early disruption. 1 0 0 - 1 0 7 The effect of hospital practices on breast-feeding. Synchronized interaction in breast-feeding, as in social exchange, is neither instinctive nor fully developed at birth. The failure of breast-feeding in industrialized societies proves that success is far from automatic. Five of six controlled studies in four countries, with both low- and middle-income women, demonstrate that hospital routines which separate mother and infant and delay nursing after birth are associated with breast-feeding for a shorter period of time. The original study compared U.S. mothers who followed an existing maternity ward routine and first nursed at 16 hours with those who nursed within one hour after birth? ~ The mothers who suckled early were much more likely to be breast-feeding when the infants were eight weeks of age. In Sweden, mothers treated routinely were compared with others who had 15 minutes of skinto-skin contact and suckled their infants immediately after birth. ''2 The mothers who had extra contact nursed an average of 2 months longer. In developing countries a shorter period of breastfeeding is .associated with increased infant morbidity and mortality. Efforts to encourage breast-feeding have generally b e e n unsuccessful. In both Guatemala and Brazil, however, investigations have demonstrated that early mother-infant contact prolongs the duration of breastfeeding. In Brazil, 77% of mothers who had extra contact and who also had the support of an enthusiastic nursing staffwere breast-feeding at two months, in contrast to 27% of those who first suckled 12 hours after birth according to routine practice? ~ A similar effect has been observed in two of three projects in Guatemala. "~ 111 In two studies mothers who had contact with their infants in the first hour were more likely to breast-feed after discharge from hospital and to breast-feed for a longer time. In the third study the results are difficult to interpret because the use of random assignment had by chance created early contact and control groups which were not comparable in socioeconomic status. The infants with early contact, however, had fewer infections in the first year in all three studies and gained significantly more weight in one study?" Early nursing may also benefit the mother by the release of maternal oxytocin to stimulate uterine contractions, which are important in expulsion of the placenta, involution of the uterus, and prevention of postpartum hemorrhage. Furthermore, breast-feeding may be impaired by other hospital routines which use intrapartum medication? ~, "~ delay nursing, 11~separate mothers and infants, ~ provide supplementary bottles, m 116~1senforce four-hour feeding

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The Journal of Pediatrics July 1977

Table II. Mother-infant social interaction a n d extra postpartum contact* Study and sample

Extra contact

Klaus and Kennell: 28 low-income U.S. 1 hr with nude newborn within 3 hr of birth mothers and infants, bottle-feeding and 5 extra hr of contact daily for 3 days (n = 14)

Hospital routine Glimpse of baby at birth, brief contact for identification at 6-12 hr, 20-30 min contact every 4 hr for feeding (n = 14)

Hales: 60 very low-income Guatemalan mothers and infants, breast-feeding

Early--45 min of private skin-to-skin contact within minutes of birth Delayed-45 minutes of private skin-to-skin contact at 12 hours (n = 20)

Glimpse of baby at birth, 12 hr separation, then daytime rooming-in for 2 days (n = 20)

Carlsson: 62 middle-class Swedish mothers and infants, breast-feeding

1 hr in bed with nude infant immediately after birth with suckling: then treated according to HR (n = 22) or allowed demand feeding, extra contact, nursing support (n = 20) 15 rain skin-to-skin contact and suckling within 20 rain of birth; then treated according to HR (n = 22)

Infant placed in crib next to mother's bed for 4 hr; then every 4 hr contact for feeding (n = 20)

deChateau: 42 middle-class Swedish mothers and infants, breast-feeding

O'Connor: 301 low-income U.S. mothers and infants

6 hr of extra contact daily for 2 days (n = 143)

Nurses care for baby for 30 min after birth; wrapped infant then placed in crib next to mother for 11/2hr; mothers and babies then separated except for every 4 hr feeds for 3 days; on days 4-7 daytime roomingin (n = 20)

20 min every 4 hr for feeding (n = 158)

EC = Extra contact; HR = hospital routine. *All studies used random group assignment, primiparous healthy mothers and infants, and observers who were unaware of mothers' postpartum

experience. schedulesJ ~9 weigh babies before and after nursing? ~ exclude fathers 1~ 1~0 and give little support to the breastfeeding mother. ~2~ 121 Early nursing has a favorable effect for w o m e n who give birth under these hospital conditions. Immediate postpartum suckling is apparently less important for effective breast-feeding when mother and infant stay together during early infancy, nursing is on demand, and people support the nursing couple. This conclusion is based on anthropologic reports that mothers start nursing on the third day or later in 58% of cultures, and in only 18% is the baby put to its mother's breast soon after birth, a22 yet in these societies failure of breast-feeding is rarely reported.

Hospital practices interfering with early maternal involvement. The social responses of healthy mothers and infants are also altered by hospital routines which involve separation. The prototype of the five studies to be described (Table II) was conducted by Klaus and associates W~ in the United States. At the time of the study the usual hospital routine provided a glimpse o f the baby in the delivery room, a six to 12-hour separation, and 20 to 30 minutes of contact every four hours for feeding thereafter. Primiparous mothers with extra contact (one

hour with their nude infants in the three hours after birth and five extra hours on each of the three days of hospitalization) behaved differently than those receiving routine care: They showed significantly more soothing, fondling, and eye-to-eye exchange during feeding at one month, 123 and at one year soothed their infants more d u r i n g the pediatrician's examination. 124 At two years mothers with extra contact spoke to their children with fewer commands, more questions, and more words per proposition. 12~ The differences between extra contact and routine care groups led the researchers to conclude that there is an early sensitive period for maternal attachment.110. 126The timing of such a "sensitive period" cannot be determined from this study because the w o m e n experienced extra contact during the hospital stay as well as early contact soon after birth. In Guatemala, primiparous mothers who received routine care were compared with others who had 45 minutes of extra contact immediately after birth (early) or at 12 hours (delayed)? 27 At 36 hours mothers who had early extra contact demonstrated more affectionate behavior (kissing, smiling, talking, looking enface considered as a group) than mothers with routine care. W h e n

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Resuhs (all differences at least significant with p < O.05)

The m o t h e r - n e w b o r n relationship

7

Conclusions

1. At 1 mo EC mothers demonstrated more soothing, fondling, and eye-to-eye contact during feeding m 2. At 1 yr EC mothers soothed the infant more during physical examination ~2" 3. At 2 yr EC mothers used more questions, fewer imperatives, and more words/propositioW ~:' 1. At 36 hr early EC mothers showed more affectionate behaviors (smiling, kissing, en face, talking, fondling) and especially more enface than either delayed EC or HR; no difference in keeping babies close or caregiving~'

Early sensitive period for maternal attachment

1. On second and fourth day EC mothers, regardless of later ward experience, showed more physical contact and physical affection (rubs, pets, rocks, touches, holds close in arms or lap.) during breast-feeding than HR mothers ~

Brief separations reduce, at least temporarily, the affective components of mother-infant interaction

1. At 36 hr EC mothers sitting up, holding, and cradling their infants more than HR mothers '~

As little as 15 min early extra contact affects both maternal and infant later behavior; more synchronous and positive mother-infant interaction apparently established

2. In hospital EC mothers carried their infants more on the left side and less in their hands away from their bodies 1~ 3. At 3 mo EC mothers kissed, look enface more, and cleaned babies less during free play in the home ~~ 4. At 3 mo EC babies smiled and laughed more and cried less 1:~~ 1. During 12-21 mo follow-up, more HR children (9) experienced abuse, neglect, abandonment, non-organic failure to thrive; one EC infant admitted for parenting failure TM behaviors were analyzed individually, looking e n f a c e was significantly decreased in both delayed extra contact and routine care groups. Early contact did not alter the mothers' caregiving or physical closeness to the baby. Thus, early extra contact seemed to encourage maternal affection. From this study it was concluded that the maternal sensitive period may be within the first 12 hours after birth. In Sweden, primiparous mothers who received one hour of contact with their naked infants immediately after birth gave their babies more physical affection during breast-feedings on the second and fourth days. ''-'~ This increase in affection occurred regardless of the amount of mother-infant contact during the rest of the hospital stay, the flexibility of the feeding schedule, or the degree of sympathetic nursing care. This study further supports the conclusion that even brief early bodily separations reduce, at least temporarily, the affective components of motherinfant interaction and indicates that the hour after birth is especially important. In another Swedish study, primiparous mothers with only 15 to 20 minutes of extra contact immediately after birth were compared with those receiving routine care. At 36 hours extra contact mothers were sitting up, holding, and cradling their infants more.'-'" In the hospital they also carried their infants

Maternal sensitive period is within the first 12 hr after birth

Extra contact benefits both subsequent mothering and child health

more on the left side and closer to their bodies. "'~ At three months mothers who had had extra contact kissed and looked at their infants en f a c e more and spent less time cleaning them during a ten-minute flee-play period in the home?:'" The infants also differed: Babies with extra contact smiled and laughed more and cried less."'" These results suggest that as little as 15 to 20 minutes of early extra contact may be associated with later differences in both maternal and infant behaviors which contribute to more responsive and positive patterns of interaction. Both studies also indicate that the physical experience of feeling and holding the baby is crucial in early contact groups, since Swedish hospital routine allows all mothers to see their babies for two or four hours after birth. Finally, in the United States 301 low-income primiparous mothers were randomly assigned to different postpartum experiences. T M One group received their babies according to the hospital routine of contact every four hours for feeding; the other group was given up to eight hours of additional daytime rooming-in. During a 12- to 21-month follow-up, only one instance of parenting disturbance required hospitalization a m o n g 134 infants whose mothers had rooming-in. In contrast, nine o f 143 infants (6.3%) whose mothers received routine hospital care were subsequently admitted lbr parenting disorders

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Lozoffet al.

(nonorganic failure to thrive, abuse, neglect, or abandonment). This project indicates that extra contact, even if not immediately postpartum, may improve both subsequent mothering and child health. Additional research will be needed to determine if contact in the hour after birth would be of even greater benefit. The importance of maternal involvement in the neonatal period is further suggested by a longitudinal Study of developmental disturbance in healthy infants.13~. 133In the days after delivery and at the end of the first month, healthy mothers were asked to rate how much they thought normal .babies cry, spit, feed, have eliminations, sleep, and are predictable. The mothers were then asked to rate their own infants on the same scale. Those mothers who perceived their babies as better than average had children with fewer later behavioral and emotional difficulties. A perception of the neonate as worse than average was predictive of problems in the children as long as 41/2 and 11 years later. Since all mothers and infants were healthy, this project ingeniously measured a mother's estimation of her own ability to synchronize with a particular infant; very few investigators have directly assessed the process of adaptation of individual mothers and babies, both of whom may have distinct and different temperaments. 1:'4-~:~6Research on maternal perceptions was conducted under hospital conditions that routinely separated mother and infant, so the possibility that early contact may further enhance mothers' positive assessment of their babies has yet to be explored. These studies suggest that for human beings, as for other mammals? 3~-1'~the amount and timing of contact with the newborn in the hours and days after birth influence early maternal involvement. Although many of the results have been explained by postulating an early maternal sensitive period, this interpretation is difficult to test directly. The infant's state has not been described in these projects, and increased infant arousal may be a major factor in early contact. In the hour after birth the newborn infant is in a heightened state of alertness and responsivity. "1 The infant is wide eyed, readily able to follow visually, responsive to the human face and voice, and eager to suckle. This eager suckling may contribute to the breast-feeding success associated with early nursing. The infant's alertness after birth may encourage the mother's affectionate responses as it does on subsequent days? ~ An increased responsivity in the mother immediately postpartum must still be postulated, however, since the opportunity to see the alert baby in the hours after birth or to interact with the alert infant on subsequent days does not have the same effect as physical contact in the first hour. Although the mechanisms by which early and extra contact affect the mother-infant relationship are

The Journal of Pediatrics July 1977

not yet understood, these studies in three different cultUres with women of different socioeconomic status all indicate, that the brief routine bodily separations of healthy mothers and infants in our hospitals interfere with early maternal affection and responsiveness. CONCLUSION Infant survival and normal development are possible within a wide but not unlimited variety of infant care practices. Through most of human history, the motherinfant relationship provided infant niitrition, warmth, protection, and social stimulation. Both mother and infant have anatomic, physiologic, and behavioral adaptations which help ensure that these survival needs are met. Remarkable and appealing neonatal capacities and early maternal responsiveness both function to initiate a specifiC relationship which protects the infant during the precarious neonatal period. I n contemporary industrialized societies the previous pattern of frequent nursing and abundant physical interaction has been replaced by one of intermittent artificial feeding and minimal contact. The evolutionary impact of this recent transformation on normal infant development and normal maternal involvement is unknown. Modern perinatal medical management has additionally imposed a pattern of early separation on mother and neonate. The research reviewed suggests that these practices are at the limits of human adaptability. Most healthy mothers and infants who are separated are subsequently able to establish synchronous interaction and an apparently satisfactory relationship. Breast feeding may fail, however, and maternal care or involvement may be impaired. PRACTICAL CONSEQUENCES These studies of interaction in the neonatal period have specific implications for pediatric practice. Although medical interference with the initiation of the parentinfant relationship may be overshadowed by disruptive Societal forces, this medical component can be eliminated. In the hospital's attempt to prevent infection and manage physical problems, separation and minimal contact between mother and infant has generally been required of all families, and thus obstetric and pediatric policies have restricted the range of choices available to parents. To provide freedom of choice to parents wishing increased involvement with their newborn infants, the following approaches are recommended: 1. Any aspect of peripartum care not based on sound scientific evidence should be left to parental choice. Such flexibility will require fresh consideration and critical evaluation of existing procedures by both medical personnel and families.

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2. O u r new awareness o f the n e o n a t e ' s capacities should be s h a r e d with families. E x a m i n a t i o n o f the n e w b o r n i n f a n t in the p a r e n t s ' presence provides a n o p p o r t u n i t y for illustrating the behaviors t h a t c o n t r i b u t e to m u t u a l interaction. 3. To s u p p o r t successful breast-feeding, we can advocate early a n d extended contact b e t w e e n m o t h e r an d infant, suckling in the first hour, f r e q u e n t nursing, elimin a t i o n of s u p p l e m e n t a r y feeding, p a t e r n a l i n v o l v e m e n t , a n d social s u p p o r t for the nursing couple. 4. To encourage the e s t a b l i s h m e n t o f an early positive m o t h e r - i n f a n t relationship, we can work to abolish hospital routines that separate m o t h e r s a n d infants. In view of the widespread disturbances in this society's families, it seems unwise to await the d e m o n s t r a t i o n of long-term irreversible consequences o f s e p a r a t i o n before early and e x t e n d e d contact are offered to all families. It should b e c o m e hospital routine for families to be together a n d for separation to occur only u p o n specific request. T h e r e is n o medical reason why healthy m o t h e r s a n d babies should not be together from the time o f b i r t h to the time o f discharge from the hospital. REFERENCES

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