kangaroo care often results in reduced hospital stays, reduced need for expensive healthcare technology, increased parental involvement and teaching opportunities, and better use of healthcare dollars. additional evidence on skin-to-skin there are a number of early studies on the impact of skin-to-skin contact on the health of all newly born humans, including an 1979 study that showed increased breastfeeding rates when skin-to-skin contact started at birth, and when early breastfeeding was encouraged every two hours. a randomized controlled trial published in 2004 reported that babies born between 1200g and 2200g became physiologically stable in skin-to-skin contact starting from birth, compared to similar babies in incubators. in another randomized controlled trial conducted in ethiopia, survival improved when skin-to-skin contact was started before 6 hours of age. in the 1990s studies began to note a series of innate behaviors in full term infants when placed in ssc with their mothers. one 2011 study described a sequence of nine innate behaviors as: the birth cry, relaxation, awakening and opening the eyes, activity (looking at the mother and breast, rooting, hand to mouth movements, soliciting sounds), a second resting phase, crawling towards the nipple, touching and licking the nipple, suckling at the breast and finally falling asleep. it is believed that this ‘sensitive period’ predisposes or primes mothers and infants to develop a synchronous reciprocal interaction pattern, provided they are together and in intimate contact. infants who are allowed uninterrupted ssc immediately after birth and who self-attach to the mother’s nipple may continue to nurse more effectively. a cochrane review on "early skin-to-skin contact for mothers and their healthy babies", updated in 2015, provided clinical support for the scientific rationale but looked at evidence for early skin-to-skin contact for healthy babies. the available evidence showed that early skin-to-skin contact was associated with increased rates of breastfeeding, and some evidence of improved physiological outcomes (early stability of the heart rate and breathing) for the babies. technique a woman holds her premature twin grandsons skin-to-skin. this position helps babies maintain the proper body temperature. kangaroo care seeks to provide restored closeness of the newborn with family members by placing the infant in direct skin-to-skin contact with one of them. this ensures physiological and psychological warmth and bonding. the parent's stable body temperature helps to regulate the neonate's temperature more smoothly than an incubator, and allows for readily accessible breastfeeding when the mother holds the baby this way. while this model of infant care is substantially different from the typical western neonatal intensive-care unit procedures, the two are not mutually exclusive, and it is estimated that more than 200 neonatal intensive care units practice kangaroo care. one survey found that 82 percent of neonatal intensive care units use kangaroo care in the united states. in kangaroo care, the baby wears only a small diaper and a hat and is placed in a flexed (fetal position) with maximum skin-to-skin contact on parent's chest. the baby is secured with a wrap that goes around the naked torso of the adult, providing the baby with proper support and positioning (maintain flexion), constant containment without pressure points or creases, and protecting from air drafts (thermoregulation). if it is cold, the parent may wear a shirt or hospital gown with an opening to the front and a blanket over the wrap for the baby. the tight bundling is enough to stimulate the baby: vestibular stimulation from the parent's breathing and chest movement, auditory stimulation from the parent's voice and natural sounds of breathing and the heartbeat, touch by the skin of the parent, the wrap, and the natural tendency to hold the baby. all this stimulation is important for the baby's development. "birth kangaroo care" places the baby in kangaroo care with the mother within one minute after birth and up to the first feeding. the american academy of pediatrics recommends this practice, with minimal disruption for babies that don't require life support. the baby's head must be dried immediately after birth and then the baby is placed with a hat on the mother's chest. measurements, etc. are performed after the first feeding. according to the us institute of kangaroo care, healthy babies should maintain skin-to-skin contact method for about 3 months so that both baby and mother are established in breastfeeding and have achieved physiological recovery from the birth process. for premature babies, this method can be used continuously around the clock or for sessions of no less than one hour in duration (the length of one full sleep cycle.) it can be started as soon as the baby is stabilized, so it may be at birth or within hours, days, or weeks after birth. kangaroo care is different from the practice of babywearing. in kangaroo care, the adult and the baby are skin-to-skin and chest-to-chest, securing the position of the baby with a stretchy wrap, and it is practiced to provide developmental care to premature babies for 6 months and full-term newborns for 3 months. in babywearing the adult and the child are fully clothed, the child may be in the front or back of the adult, can be done with many different types of carriers and slings, and is commonly practiced with infants and toddlers. rationale in primates, early skin-to-skin contact is part of a universal reproductive behaviour, and early separation is used as a research modality to test the harmful effects on early development. research suggests that for all mammals, the maternal environment (or place of care) is the primary requirement for regulation of all physiological needs (homeostasis), maternal absence leads to dysregulation and adaptation to adversity. in mainstream clinical medicine, kangaroo mother care is used as an adjunct to advanced technology that requires maternal infant separation. however, skin-to-skin contact may have a better scientific rationale than the incubator. all other supportive technology can be provided as part of care to extremely low birth weight babies during skin-to-skin contact, and appears to produce a better effect. based on the scientific rationale, it has been suggested that skin-to-skin contact should be initiated immediately, to avoid the harmful effects of separation (bergman curationis). in terms of classification and proper defining for research purposes, the following aspects that categorise and define skin-to-skin contact have been proposed: initiation time, (minutes, hours from birth), ideal is zero separation. dose of skin-to-skin contact, (hours per day, or as percentage of day), ideal >90%. duration, (measured in days or weeks from birth), ideally until infant refuses. safe technique should ensure that obstructive apnoea cannot occur. since the mother must be able to sleep to provide adequate dose, this requires keeping the airway safely open, and close containment to mother's bare chest using a garment, various of these are described in the who guidelines. mother should be the primary provider of skin-to-skin contact, as only she can breastfeed. however, it is almost always necessary that father should also provide skin-to-skin contact to achieve adequate dose; other family members can also be used. since skin-to-skin contact is basic to early bonding and attachment, it should probably not be done by hospital staff and other surrogates. terminology kangaroo care is likely the most widely used term in the united states for skin-to-skin contact. gene cranston anderson may have been the first to coin the term kangaroo care in the usa. the defining feature of this is however for skin-to-skin contact, commonly abbreviated as ssc, also sts. this is used synonymously with "skin-to-skin care". dr nils bergman, one of the founders of the kangaroo mother care movement, argues that since skin-to-skin contact is a place of care, not a kind of care in itself, skin-to-skin contact should be the preferred term. kangaroo mother care is a broader package of care defined by the world health organization. kangaroo mother care originally referred only to care of low birth weight and preterm infants, and is defined as a care strategy including three main components: kangaroo position, kangaroo nutrition and kangaroo discharge. kangaroo position means direct skin-to-skin contact between mother and baby, but can include father, other family member or surrogate. the infant should be upright on the chest, and the airway secured with safe technique. (the term kangaroo mother care is commonly used to mean skin-to-skin contact, despite its definition from the who as including a broader strategy). kangaroo nutrition implies exclusive breastfeeding, with additional support as required but with the aim of achieving ultimately exclusive breastfeeding. kangaroo discharge requires that the infant is sent home early, meaning as soon as the mother is breastfeeding and able to provide all basic care herself. in colombia in 1985 this took place at weights around 1000g, with oxygen cylinders for home use; the reason was that overcrowding in their hospital meant that three babies in an incubator would result in potentially lethal cross-infections. an essential part of this is close follow-up, and access to daily visits. history an early example of skin-to-skin infant care is the traditional inuit woman's garment, the amauti, had a large pouch at the back where the baby would sit against the mother's bare back. this skin-to-skin approach is also present in many other cultures around the world. peter de chateau in sweden first described studies of "early contact" with mother and baby at birth in 1976, articles do not describe specifically that this was skin-to-skin contact. klaus and kennell did very similar work in the us, more well known in the context of early maternal-infant bonding. the first reported use of the term "skin-to-skin contact" is by thomson in 1979 and quotes the work of de chateau in its rationale. the inception of kangaroo mother care happens in bogota, colombia., which included the use of skin-to-skin as part of a multi-prong approach to lbw infant care, together with exclusive breastfeeding, early discharge, among other aspect. in 1978, due to increasing morbidity and mortality rates in the instituto materno infantil nicu in bogotá, colombia, dr. edgar rey sanabria, professor of neonatology at department of paediatry - universidad nacional de colombia, and the next year dr. hector martinez gomez as coordinator, introduced a method to alleviate the shortage of caregivers and lack of resources. they suggested that mothers have continuous skin-to-skin contact with their premature or low birth weight babies to keep them warm and to give exclusive breastfeeding as needed. this freed up overcrowded incubator space and care givers. skin to skin contact is the cornerstone of kmc, and initially adopted with the goal of thermal regulation. the skin to skin contact of the kangaroo position is done in an upright prono position, preferably on the mother, in a frog position and with an elastic support that allows a support of the position at the same time as it allows the child to make small movements as when he was in the womb. it is necessary to ensure the freedom of the respiratory tract, the position is continuous to ensure the thermal regulation or alternates with an incubator if the child or his mother does not tolerate the position anymore. the mother learns to feed the baby at short intervals. as soon as the mother feels able to carry her growing baby and feed it, she can go home with a close monitoring and this method of care is called kmc. another feature of kangaroo care was early discharge in the kangaroo position despite prematurity. it has proven successful in improving survival rates of premature and low birth weight newborns and in lowering the risks of nosocomial infection, severe illness, and lower respiratory tract disease. it also increased exclusive breastfeeding and for a longer duration and improved maternal satisfaction and confidence. dr rey and dr martinez published their results in 1981 in spanish, and used the term kangaroo mother method. this was brought to the attention of english speaking health professionals in an article by whitelaw and sleath in 1985. gene cranston anderson and susan ludington were instrumental in introducing this to north america. in 1989, a group of health professionals, including dr. nathalie charpak, began the evaluation and dissemination of kmc in colombia and began applying a scientific rigorous research approach to demonstrate the safety and effectiveness of kmc. in 1994, they created the fundacion canguro o kangaroo foundation, which has trained almost a hundred medical teams from more than 50 countries in kmc. the foundation