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Bonding: Recent Observations That Alter Perinatal Care

1998; American Academy of Pediatrics; Volume: 19; Issue: 1 Linguagem: Inglês

10.1542/pir.19.1.4

1529-7233

John H. Kennell, Marshall H. Klaus,

Assisted Reproductive Technology and Twin Pregnancy

For almost three decades, there has been special interest in the bond between parents and their infants in the hope that better understanding of this relationship could result in improved perinatal care routines and a reduced incidence of parenting disorders such as child abuse, neglect,failure to thrive, and abandonment. Recent research findings provide a compelling rationale for major changes in some birth practices related to the bonding process.The term bonding refers to the emotional tie from parent to infant; attachment generally is used for the tie from infant to parent. A bond can be defined as the unique relationship between two people that is specific and endures through time. Parenteral bonds to their child can persist during long separations of time and distance, even though visible signs of their existence may not be apparent.Abandonment in this article refers to the caretaker, usually the mother, relinquishing all responsibility and care for an infant, usually in the first hours after delivery, by leaving the baby in the hospital and disappearing. A doula is a caring woman experienced in childbirth who provides continuous physical and emotional support to the mother during and for a short time immediately after childbirth.Researchers have questioned whether a period of time for parent-infant contact in the first minutes, hours, or days of life may alter the parents' later behavior with that infant. In biologic fields,these moments have been called sensitive periods. As an example, a mother received analgesic medication 1 hour before she delivered her baby, and she was asleep when the baby was born. When she awoke, she thought her baby was a boy, so she was upset when the nurse brought an infant girl. It took 12 days for her to appreciate that she had a girl. This confusion probably could have been avoided if she had received no medication and was given her baby immediately. At a recent visit to her pediatrician, she said jokingly,"I still wonder if she is my baby."A critical period in biology refers to a circumscribed time during which an embryologic feature (eg, the effect of thalidomide) or a behavior develops. If this period passes without a certain event occurring, such as contact of a mother animal with her newborn, the usual parent-infant bonding will not occur and generally cannot be recaptured at a later time. (This is not appropriate terminology for human parent-to-infant bonding; early separation does not prevent formation of a close, intimate bond.)As vital as the first hours may be for the interaction of mother and infant, they should not be expected to produce instant feelings of love for the infant by the mother and the father. When MacFarlane asked 97 mothers, "When did you first feel love for your baby?", 41% said during the pregnancy and 24% said at birth, but 27% said that it was during the first week and 8%said after the first week. In a randomized controlled trial of doula support in South Africa, the women in the continuously supported group took 2.9 days to feel the baby was their own compared with 9.8 days for mothers who labored without doula support. The mother's feeling of love for her baby is not instantaneous, but the first hour appears to be an especially valuable time in the bonding process.The attachment or bonding of a parent to an infant begins during pregnancy and increases shortly after birth. The bonds from the caretaker(s),usually the mother and father, to the infant are crucial for the baby's survival and development. The power of this attachment is so great that it enables the mother and father to make the many sacrifices necessary for the care of their infant attending to the infant's crying, protecting the baby from danger, and providing feedings in the middle of the night, despite their own desperate need for sleep.An understanding of bonding, as well as research on this topic, has been hampered by the lack of any simple measurement of its strength. The presence of mother-to-infant bonding has been assessed by measuring some aspect of maternal care or behavior.The wise pediatrician will keep in mind that the mother's behavior with her infant is influenced by many factors. An example of a cultural factor is the concern of some Southeast Asian mothers that the"evil eye" will harm their babies if they show admiration and love, so they do not look "en face" and keep the baby at the foot of their beds in old disheveled clothes. The powerful effect of a mother's own early experiences is demonstrated by George Engel's long-term study of Monica, 1who had esophageal atresia and required gastrostomy feedings during her first year. She fed her dolls and then her four daughters in the same way she had been fed, lying horizontally on her lap(Fig. 1 ).The practices of a mother's culture, her relationship with the father,the amount of support he provides, and the mother's emotional state (eg,positive self-esteem or depression) may influence the mother's behavior with her new infant. As an example, mothers who had continuous support by a doula during labor and delivery showed more affectionate interaction with their infants after leaving the delivery room than mothers who did not have a doula. They were less willing to leave their babies alone, and they reported picking up their babies more frequently when they cried. A higher percentage of supported mothers not only considered their babies beautiful, clever,healthy, and easy to manage, but believed that their babies cried less than other babies. In fact, more of the supported mothers believed that their babies were "better" when compared with a "standard baby."In contrast, the nonsupported mothers perceived their babies as"almost as good as" or "not quite as good as" a standard baby. In addition, seven randomized trials revealed that women who received continuous support in labor with a doula had a 25% reduction in the length of labor, greater than 50% reduction in cesarean deliveries, and required significantly less oxytocin, medication, and operative vaginal deliveries.Although it has been helpful to examine a mother's or father's behavior with a baby, this may be misleading. In a hospital study in the United States that tested criteria for potentially abusive mothers, 30%of the new mothers were identified as potentially abusive, but follow-up of the women and their newborns disclosed no evidence of a parenting disorder. When observed, a drug-abusing mother may appear to have great love for her newborn, but the next minute she may leave the infant on the table unattended. No reliable and simple test is available to distinguish parents who will abuse.A special area of bonding studies has focused on increasing mother-infant time together through simple, low-cost intervention in the first hours and days following birth.One of the most significant findings in this early period is related to breastfeeding. Six of nine studies revealed that when a mother wants to breastfeed, is permitted to have early contact with her infant with an opportunity for suckling in the first hour of life, and is rooming-in with her infant, she is more successful than mothers who do not have these experiences. She succeeds in initiating breastfeeding and is able to breastfeed for a longer period than mothers who do not have early contact and rooming-in with their babies (Fig. 2).In addition, studies of Brazelton and others have shown that if nurses spend as little as 10 minutes helping mothers discover some of their newborn infants' abilities, such as turning to the mother's voice and following the mother's face or imitation and assisting mothers with suggestions about ways to quiet their infants, the mothers became more appropriately interactive with their infants face to face and during feedings at 3 and 4 months of age.O'Connor and colleagues carried out a randomized trial with 277 mothers in a hospital that had a high incidence of parenting disorders. One group of mothers had their infants with them for 6 additional hours on the first and second day, but no early contact. The routine care group began to see their babies at the same age but only for 20-minute feedings every 4 hours,which was the custom throughout the United States at that time. In follow-up studies, 10 children in the routine care group experienced parenting disorders,including child abuse, failure to thrive, abandonment, and neglect during the first 17 months of life compared with two cases in the experimental group, who had 12 additional hours of mother-infant contact. A similar study in North Carolina that included 202 mothers during the first year of life did not find a statistically significant difference in the frequency of parenting disorders; 10 infants failed to thrive or were neglected or abused in the control group compared with seven in the group that had extended contact. When the results of these two studies are combined in a meta-analysis, it appears that simple techniques, such as adding additional early time for each mother and infant to be together and closing the newborn nursery, may lead to a significant reduction in child abuse. However, a much larger study will be necessary to confirm and validate these relatively small studies.Publication of these studies stimulated a lively debate in the early 1980s about the significance of the findings. Michael Lamb, the major critic, published somewhat similar objections almost simultaneously in Pediatrics and The Journal of Pediatrics. He expressed concern about failure to replicate findings and methodologic problems and suggested that " although early contact may have modest but beneficial short-term effects in some circumstances, no positive long-term effects have been demonstrated." The multiple inaccuracies in his review have resulted in some confusion and misunderstanding among those not well-acquainted with the field as well as an inability to reconcile completely differences in the evaluation and interpretation of each study. Diane Eyer,author of Mother-Infant Bonding—A Scientific Fiction, and Lamb were particularly critical of the practice of aiding the study of parental attachment in humans with observations in animal mothers. As noted previously in this article, this was not designed to explain human behavior, but to provide a view of humans within the context of evolutionary development. The approach was used cautiously, quoting Schneirla, "While …. analogy has an important place in scientific theory, its usefulness must be considered introductory to a comparative study in which differences may well be discovered that require a reinterpretation of the similarities first noted."For further discussion of this controversy, see the two reviews of Lamb and two short rebuttals by Anisfeld and associates and Klaus and Kennell (see Suggested Reading).In the 14 years since the conclusion of the overt controversy, several physiologic and behavioral studies of mothers and infants have added new and critical information. Both mother and infant bring a wealth of internal resources to their early moments together.Perhaps the most revealing example is the ability of newborns, if left quietly on the mother's abdomen after birth, to crawl gradually up to her breast, find the nipple, and start to suckle (Fig.3F3). If the mother has received no pain medication during labor and birth and the infant is dried thoroughly, placed on her abdomen, kept warm with the heat of her body and a towel, and not taken from her for the next 60 minutes,the baby usually begins a five-part sequence that ends with proper latching onto the mother's nipple. For the first 20 minutes, the newborn rests and looks up periodically at the mother. At 30 to 45 minutes, mouthing and lip-smacking movements begin, and the infant begins to drool. The baby then begins to move forward slowly, starts to turn the head from side to side,and opens the mouth widely upon nearing the nipple. After several attempts,the lips latch onto the areola, not the nipple. The odor of the nipple appears to guide the newborn to the breast. When the right breast is washed,the baby goes to the left breast.In one group of mothers who did not receive pain medication and whose babies were not taken away during the first hours of life for a bath, vitamin K administration, or application of eye ointment, 15 of 16 babies were observed to make this trip on their own and to begin to suckle effectively. These and other observations have made us question our present policy of putting infants to the breast immediately after birth. This newly discovered process suggests that the newborn, after recovering from the stress of birth, begins suckling and is ready to eat at a more appropriate time, when he or she is ready.Swedish researchers have shown that the normal infant, when dried and placed nude on the mother's chest and then covered with a blanket,will maintain his or her body temperature as well as when elaborate, high-tech heating devices that usually separate the mother and baby are used. The same researchers found that when the infants are skin-to-skin with their mothers for the first 90 minutes after birth, they cry hardly at all compared with infants who were dried, wrapped in a towel,and placed in a bassinet (Fig. 4). It seems likely that each of these features—the crawling ability of the infant, the decreased crying when close to the mother, and the warming capabilities of the mother's chest—are adaptive and evolved genetically more than 400,000 years ago to help preserve the infant's life.When the infant suckles from the breast,there is a large outpouring of 19 different gastrointestinal hormones in both the mother and the infant, including cholecystokinin and gastrin, which stimulate growth of the baby's and mother's intestinal villi and increase the surface area and the absorption of calories with each feeding. The stimuli for this release are touch on the mother's nipple and the inside of the infant's mouth (Fig. 5). These responses were essential for survival thousands of years ago when periods of famine were more common before the development of modern agriculture and the storage of grain.These new research findings explain some of the underlying physiologic processes and provide additional support for the importance of two of the ten caregiving procedures that the United Nations International Children's Emergency Fund (UNICEF) is promoting as part of its Baby Friendly Initiative to increase breastfeeding: 1) early mother-infant contact, with an opportunity for the baby to suckle in the first hour and 2) mother-infant rooming-in throughout the hospital stay.Following the introduction of the Baby Friendly Initiative in maternity units in several countries throughout the world, an unexpected observation was made. In Thailand, in a hospital where a disturbing number of babies are abandoned by their mothers,the use of rooming-in and early contact with suckling significantly reduced the frequency of abandonment from 33/10,000 births to 1/10,000 births a year. Similar observations have been made in Russia, the Philippines, and Costa Rica when early contact and rooming-in were introduced.These reports further suggest that events occurring in the first hours and days after birth have special significance, and they are additional evidence that the first hours and days of life are a sensitive period for the human mother. This may be due in part to the special interest that mothers have shortly after birth in hoping their infant will look at them and the interacting behavior of the infant in the first hour of life during the prolonged period of the quiet alert state. Thus, there is a beautiful interlocking at this early time of the mother's interest in the infant's eyes and the baby's ability to interact and to look eye-to-eye.A possible key to understanding what is happening physiologically in the first minutes and hours comes from investigators who noted that if the lips of the infant touch the mother's nipple in the first hour of life, a mother will decide to keep her baby 100 minutes longer in her room every day during her hospital stay than another mother who does not have contact until later.In sheep, dilation of the cervical os during birth releases oxytocin within the brain that, acting on receptor sites, appears to be important for the initiation of maternal behavior and for the facilitation of bonding between mother and baby. In humans, there is a blood-brain barrier for oxytocin, and only small amounts reach the brain via the blood stream. However, multiple oxytocin receptors in the brain are supplied by production from the brain. Increased levels of brain oxytocin result in slight sleepiness, euphoria, a raised pain threshold, and feelings of increased love for the infant. It appears that during breastfeeding, raised blood levels of oxytocin are associated with increased brain levels; women who exhibit a high plasma oxytocin concentration are the most sleepy.Measurements of plasma oxytocin levels in 18 healthy women who had their babies skin-to-skin on their chests immediately after birth showed significant elevations compared with the prepartum levels and a return to prepartum levels at 60 minutes. For the majority of women, a significant and spontaneous peak concentration was recorded about 15 minutes after delivery,with expulsion of the placenta. Most mothers had several peaks of oxytocin up to 1 hour after delivery. The vigorous oxytocin release after delivery and with breastfeeding not only may help contract the uterine muscle to prevent bleeding, but may enhance bonding of the mother to her infant. These findings may explain an observation made in France in the 19th century when many mothers were giving up their babies. Poor mothers who breastfed for at least 8 days rarely abandoned their infants. We hypothesize that a cascade of interactions between the mother and baby occurs during this early period,locking them together and ensuring further development of attachment. The remarkable change in maternal behavior with just the touch of the infant's lips on the mother's nipple; the reduction in abandonment with early contact, suckling, and rooming-in; and the raised maternal oxytocin levels shortly after birth in conjunction with known sensory, physiologic,immunologic, and behavioral mechanisms all contribute to the attachment of the parent to the infant.Although debate continues on the interpretation and signficance of the many research studies regarding the effects of early and extended contact for mothers and fathers on bonding with infants, all sides agree that all parents should be offered such contact time with their infants. Thompon and Westrich, in their recent extensive critical review of obstetrical and neonatal care, reached the following conclusions regarding a sensitive period:"We have been unable to find any evidence suggesting that the restriction of early postnatal mother-infant interaction, which has been such a common feature of the care of women giving birth in hospitals, has any beneficial effects. On the contrary, the available evidence suggests that any effects that these restrictive policies have are undesirable. The data suggest the plausible hypothesis that women of low socioeconomic status may be particularly vulnerable to the adverse effects of restricting contact."It may be thought surprising that disruption of maternal-infant interaction in the immediate postnatal period may set some women on the road to breast-feeding failure and altered subsequent behavior towards their children. Pediatricians, psychologists, and others have indeed debated this issue. This skepticism does not, however, constitute grounds for acquiescing in hospital routines which lead to unwanted separation of mothers from their babies. In the light of the evidence that such policies may actually do harm,they should be changed forthwith."Another intervention that appears promising has been reported by Anisfeld, who observed a low incidence of secure attachment behavior at 1 year in a poor, stressed urban population where most of the mothers put young infants in firm plastic infant seats throughout the first year. In nonindustrialized societies, where most babies are carried on the mother's body through the day and sleep with the mother at night, there is much less infant crying. Drawing on the idea that increased physical contact would promote greater maternal sensitivity to the signals of the infant and, thus, increased responsiveness, Anisfeld and associates conducted a randomized study in which one group of babies was carried on the mother's body in a soft baby carrier and another group was placed in firm infant seats that provided less contact. When the infants were assessed in the home at 3 months by naive observers, the mothers using the soft baby carriers were more appropriately interactive and responsive to their babies' cues. When all the infants reached 13 months of age, the Ainsworth Strange Situation test was applied; 83% of the babies carried in the soft carrier were securely attached compared with 39% of the infants from the group that used the firm infant seats.The significant effects of the first hours and days are explained in part by observations noted by Winnicott, who reported a special mental state of the mother in the perinatal period that involves a greatly increased sensitivity to, and focus upon, the needs of her baby. He indicated that this state of "primary maternal preoccupation" starts near the end of pregnancy and continues for a few weeks after the birth of the baby. A mother needs nurturing support and a protected environment to develop and maintain this state. This special preoccupation and the openness of the mother to her baby are key factors in the bonding process. Winnicott wrote that "Only if a mother is sensitized in the way I am describing, can she feel herself into her infant's place, and so meet the infant's needs." In the state of "primary maternal preoccupation," the mother is better able to sense and provide what her new infant has signaled, which is her primary task. If she senses the needs and responds to them in a sensitive and timely manner, mother and infant will establish a pattern of synchronized and mutually rewarding interactions. It is our hypothesis that as the mother-infant pair continues this dance pattern day after day, the infant more frequently will develop a secure attachment, with the ability to be reassured by well-known caregivers and the willingness to explore and master the environment when caregivers are present. In a sense, the child becomes an optimist rather than a pessimist. The characteristics of a secure attachment,if present at 1 year of age, usually persist through childhood and into adult life.Although many changes have been made in the perinatal caregiving environment over the past 10 years, it is apparent that further changes are required,including the institution of early skin-to-skin contact and extended maternal caregiving with rooming-in for all healthy mothers. In addition,further detailed research is needed to discover how synchrony of mother and infant develops in the early days of life, and if early attunement leads to a mother who is responsive, attentive, and sensitive to the unique signals and needs of her own baby. It appears that this type of maternal behavior during the first year of life will lead more frequently to a securely attached and appropriately independent child who develops a basic sense of trust in the world.Fathers are expected to be present during labor and delivery in United States hospitals, and a Gallup poll shows that 80% of mothers have the father present. In surveys, mothers express a belief that it is extremely important for the father to be present during labor and delivery, and fathers express a desire to be present. This assures that most fathers are available for early contact with newborns. Research has shown that paternal caretaking and affectionate interaction with the baby is increased in the first 3 months if the father has experience with his undressed baby, changing diapers and looking "en face" in the first 3 hours of life. Sharing the intimate experience of the birth of the baby and interaction afterward gives fathers a feeling of increased closeness to their wives. Adolescent fathers are often ill-prepared for establishing the family unit with their poor parenting skills, immaturity,inconsistent involvement with the mother and infant, and low income. Research shows that if fathers of children born to adolescent mothers attend prenatal visits and participate during labor and delivery, they are significantly more likely to have monthly or more frequent visits with their child in the first 2 years of their life.The United States stands out for its lack of societal or governmental public health service support for mothers and babies during the postpartum period. In contrast, it is the practice in 183 of 186 representative nonindustrialized cultures for the mother and the baby to be isolated, protected, fed, and guided during at least the first 7 days, 6 weeks in many cultures, and 6 months to 1 year in others. Discussions with the parents about the need for extra postpartum support prior to the birth of the baby can expedite the mother's bonding with her infant by minimizing postpartum fatigue, irritability, and depression.Parents who give birth to a preterm or sick newborn generally have two different coping styles and personal adaptations to the stress. Some commit to the baby and maintain an intense involvement. Others choose a slower acquaintance process in which they rely on the care provided by the experts and express fear, anxiety, and sometimes denial before accepting the surviving infant. Parents must reconcile their idealized mental image of the expected baby with the tiny, weak, and scrawny infant. It is difficult for them to appreciate that this baby will grow into a normal, husky, vigorous youngster.Als and colleagues have developed a sensitive instrument to assess the special needs of preterm infants. With this information, an individualized care plan can be created for each infant, taking into account what the infant is seen to experience as soothing or disruptive. This process of evaluation and development of a plan is repeated about once a week. Each infant's requirements for light,sound, rest position, and special nursing care can have a significant impact on his or her recovery and progress. In three randomized trials that have used this approach, the experimental infants required less time on a respirator and less oxygen and were discharged home earlier. Following discharge, their development progressed more normally. The parents profited from the experience of assisting with the observations and helping in the development of the care plan.Carefully conducted studies in industrialized countries have shown that stable infants weighing 1,361 g (3 lb) can be held safely skin-to-skin with an adult in a neonatal intensive care nursery. Babies' body temperatures are well maintained by the warmth of the mother's or father's body when the baby wears a cap and is covered by a light blanket. The baby's Po2 levels are higher when the baby is skin-to-skin with the parent for periods of up to 2 to 3 hours a day. After the skin-to-skin experience, mothers feel more confident in the nursery and increase their milk output at home. Although skin-to-skin contact is very helpful for mothers,data are not sufficient to sup-port sending small preterm infants home using the kangaroo method.In several countries, mothers of preterm infants live in a room adjoining the preterm nursery or room-in with their infant. This arrangement allows the mother to care for the baby more easily, helps her continue to produce milk,reduces the caregiving time required by the nursery staff, and offers the mother the advantage of living with a group of mothers in similar circumstances who can provide mutual support. Most of the experience has been with mothers living in from shortly after the birth of the baby until discharge, but there also has been experience with mothers living in and caring for their babies for 3 days prior to discharge. This gives mothers increased confidence and improves their caregiving skills. In these live-in situations, the mother should be considered the responsible caregiver, with the nurse functioning as a consultant.Helping families after a neonatal death or a stillbirth presents substantial challenges. Physicians who can express their sorrow about the loss and listen to the comments and reactions of the bereaved family may be providing benefits that could be greater than the other services they usually provide. After the loss, parents, siblings, and other family members are in a state of intense emotional turmoil; their normal coping mechanisms are temporarily ineffective. Seeing, touching, and holding the body of the baby facilitates the work of grieving. This opportunity may not be provided after a stillbirth or a neonatal death unless the physician arranges it. Some bereaved individuals may attempt to avoid the painfulness of the death by not seeing or holding the baby or talking about the loss. This avoidance blocks rather than helps the mourning response, and the feelings associated with the tragic loss may reappear in some form following the birth of a healthy infant. Information from the physician is helpful, but details provided in the early stages of shock and numbness will require repeating later. Many patients experience severe reactions, with disruptions of their thoughts and the usual patterns of life for the first 3 to 6 months. After the 1-year anniversary, many parents still think of the bereaved baby every day, but it is not such an intrusive concern.After a perinatal death,anxiety and anger are common, with blame being directed at the staff or other members of the family. In addition, one or both parents may direct these feelings toward themselves, manifested as guilt. Parents frequently are distressed by unusual sensory experiences, such as hearing the dead baby crying or seeing the baby as they look at a blank wall. Most parents are surprised at the emotional turmoil associated with a grief reaction and its long duration. Sexual and marital difficulties are common. Mothers comment about their loss of self-esteem and their sense of failure. These mourning reactions after a stillbirth demonstrate that the parents' bond to the infant is present prior to birth. Parents who initially do not wish to see or hold a dead infant eventually may agree when they are informed that this experience helps in mourning the loss and that the opportunity to have contact with the baby will not be available after 2 or 3 days or after cremation. Almost all consent when they are given time, the offer is repeated 1 or 2 hours later, and the baby's body is kept on the unit. The parents should be encouraged to examine, dress, and undress their infant as they wish; many subsequently are extremely grateful for the experience. The parents also should be informed about the long-term benefits of obtaining pictures, footprints, locks of hair, hospital bracelets, and underclothes as tangible reminders of the baby, but they never should be pushed or coerced into any of these interactions. The task of each caretaker is to determine the parents' mental and emotional states and to proceed in the direction indicated by the parent. A major obligation of the pediatrician is to help the parents communicate with their surviving children and, in many situations, to arrange for a person not so affected by the loss to support the children and provide answers to their questions.The mother who gives up her baby for adoption will also have mourning reactions that require similar attention and listening to her reactions and comments.Studies and observations made over the past 30 years have led our research group to the formulation of principles that may govern the parents' attachment to their infant. The strength of the data for each principle varies and comes from clinical experience and research studies. 1More than 40 years ago, a group of researchers in the Department of Psychiatry at the University of Rochester began the longest continuous developmental study of an individual documented on film and videotape. The study of Monica, an infant who was born with esophageal atresia and who was fed through a gastric fistula until she was 2 years old, is a classic in the medical literature. In 3 hours of compelling and, at times,spell-binding videotapes, George L. Engel, MD,narrates a distillation of this unique study,which now includes Monica and her grandparents, parents, siblings, and children. Three videotapes summarizing the first 30 years of Monica's life are available for purchase by qualified professionals. For more information contact: George L. Engel, MD,University of Rochester School of Medicine,300 Crittenden Blvd, Rochester, NY, 14642. Phone: 716-275-3585.