Kangaroo care

Kangaroo mother care, which involves skin-to-skin contact, is an intervention to care for premature or low birth weight infants. The technique and intervention is the recommended evidence-based care for LBW infants by the World Health Organization since 2003.
In the 2003 WHO Kangaroo Mother Care practical guide, KMC is defined as a "powerful, easy-to-use method to promote the health and well-being of infants born preterm as well as full-term", with its key components being:

Early, continuous, and prolonged SSC between the mother and the baby;
Exclusive breastfeeding ;
Initiated in a hospital setting and can be continued at home;
Allows for early discharge of the baby to the family;
After discharge, includes close followup

The early KMC technique was first presented by Rey and Martinez in 1983, in Bogotá, Colombia, where it was developed as an alternative to inadequate and insufficient incubator care for those preterm newborn infants who had overcome initial problems and required only to feed and grow. Decades of research and development, much from researchers from emerging economies, has improved upon the initial work and has documented that modern evidence-based KMC lowers infant mortality and the risk of hospital-acquired infection, increases weight gain of infants, increases rates of breastfeeding, protects neuromotor and brain development of infants, and improves mother-infants bonding, among other benefits. Today, the WHO recommends "Kangaroo mother care for preterm or low-birth-weight infants should be started as soon as possible after birth" based on "high-certainty evidence".

Scientific documentation of benefits

Originally babies who were eligible for KMC included LBW infants weighing less than and breathing and eating independently. Cardiopulmonary monitoring, oximetry, supplemental oxygen or nasal ventilation, intravenous infusions, and monitor leads do not prevent KMC. In fact, babies who are in KMC tend to be less prone to apnea and bradycardia and have stabilization of oxygen needs.
KMC has been shown to provide many benefits to the infant, as well as to the family directly involved in the infant's care. Large reviews of the thousands of scientific articles that present the body of evidence have been published, that serve as the bases for practical guides for practitioners.
After initial reviews of scientific evidence in the mid-1990s highlighted research ongoing in both developed and developing countries, research into KMC grew exponentially. Systematic reviews of hundreds of scientific articles have documented the impact of KMC on mortality, morbidity, and quality of survival LBW infants.
A randomized controlled trial published in 2016 reported that babies born between became physiologically stable in SSC starting from birth, compared to similar babies in incubators. A descriptive study of case series in a hospital without any technical resources evaluated two of the components of the KMC: the inpatient kangaroo position and kangaroo feeding and was published in 1994. This paper supports the hypothesis that, in cases of absence of technical resources, inpatient kangaroo position and nutrition is an acceptable alternative.
In 2016, a Cochrane review, "Kangaroo mother care to reduce morbidity and mortality in low birthweight infants", was published bringing together data from 21 studies including 3,042 LBW babies. This review showed that babies receiving kangaroo care had a reduced risk of death, hospital-acquired infection, and low body temperature ; was also associated with increased weight gain, growth in length, and rates of breastfeeding.

Preterm and LBW infants

Kangaroo care "is an effective and safe alternative to conventional neonatal care for LBW infants, mainly in resource-limited countries". KMC reduces mortality, and also morbidity in resource limited settings, though further studies are needed.
Kangaroo care arguably offers the most benefits for preterm and LBW infants, who experience more normalized temperature, heart rate, and respiratory rate, increased weight gain, and fewer hospital-acquired infections. Additionally, studies suggest that preterm infants who experience kangaroo care have improved cognitive development, decreased stress levels, reduced pain responses, normalized growth, and positive effects on motor development. Kangaroo care also helps to improve sleep patterns of infants and may be a good intervention for colic. Earlier discharge from hospital is also a possible outcome Finally, kangaroo care helps to promote frequent breastfeeding and can enhance mother–infant bonding. Evidence from a recent systematic review supports the use of kangaroo mother care as a substitute for conventional neonatal care in settings where resources are limited.

For parents

Kangaroo care is beneficial for parents because it promotes attachment and bonding, improves parental confidence, and helps to promote increased milk production and breastfeeding success.
A 2017 study found that the psychological benefits of kangaroo care for parents of preterm infants are fairly extensive. Research shows that the use of kangaroo care is linked to lower parental anxiety levels. It was shown to decrease anxiety scores in both mothers and fathers, unrelated to parents' marital status. Kangaroo care has also been shown to lead to greater confidence in parenting skills. Parents who used kangaroo care displayed higher confidence in their ability to care for their child. It has been shown to positively impact breastfeeding as well, with mothers producing larger amounts of milk for longer periods of time.

For fathers

Both preterm and full term infants benefit from SSC for the first few weeks of life with the baby's father as well. The new baby is familiar with the father's voice, and it is believed that contact with the father helps the infant to stabilize and promotes father to infant bonding. If the infant's mother had a caesarean birth, the father can hold their baby in SSC while the mother recovers from the anesthetic.
A 2016 study looked at international literature reviews of early SSC benefits for infants and fathers. Their findings for infants included:

Swedish and German reviews found that father SSC is as effective as mother SSC in raising a baby's temperature, and there is no difference between father and mother skin-to-skin on biophysical measures of the baby's expenditure of energy.
A Swedish review found that babies experiencing father SSC had significantly higher blood glucose levels than babies who were placed in an incubator. A higher glucose level protects a baby from cold temperatures.
A Swedish review found that babies who experienced father SSC showed lower levels of salivary cortisol when handled, which indicates a lower stress response.
A Swedish review found that babies receiving father SSC were more easily comforted and stopped crying more quickly than babies that had been separated from a parent.
A Swedish review found that prefeeding behaviors, such as rooting and sucking, were less frequent among the infants who received father SSC. Infants receiving father SSC started breastfeeding a little later than those receiving SSC only from their mothers.

Looking at the review, researchers found that SSC was of benefit to fathers as well. Their findings included:

A Colombian study focused on India found that fathers who provided SSC to preterm infants exhibited more caring behaviours and developed a more sensitive approach to their infants.
A Colombian randomized control trial found that after a pre-term birth, father SSC was linked to better cognitive development of the infant and more engagement by the father when the couple returned to their home.
Reviews done in the US and Sweden showed that fathers who provided SSC felt less stress, were less anxious, and had a better relationship with the mother.
Reviews done in Denmark and Sweden found that father SSC, like mother SSC, promotes verbal interaction between infant and parent within minutes of the birth. The review also found that fathers who have experienced SSC participated more in infant care and felt more in control when handling unexpected situations.
Following cesarean section birth

Although the WHO and UNICEF recommend that infants born by cesarean section should also have SSC as soon as the mother is alert and responsive, a 2014 review of medical literature found that many hospitals were not providing SSC following a C-section. Immediate SSC following a spinal or epidural anesthetic is possible because the mother remains alert; however, after a general anesthetic, the father or other family member may provide SSC until the mother is able.
It is known that, during the hours of labor before a vaginal birth, a woman's body begins to produce oxytocin which aids in the bonding process, and the authors believe that SSC can be of special importance following a C-section birth. Indeed, women reported that they felt that SSC had helped them to feel close to and bond with their infant. The review reported comments made by mothers such as "My baby calms down right away when I put him to my chest. I don't know if it's related to holding him skin‐to‐skin during the cesarean—but I think it is." Newborns were also found to cry less and relax quicker when they had SSC with their father as well. There is evidence that women who give birth by C-section are less likely to breastfeed and those that do have increased difficulties in establishing breastfeeding. The review, however, found that immediate or early SSC increased the likelihood of successful breastfeeding.

Promotes breastfeeding

According to some authorities, there is a growing body of evidence that suggests that early SSC of mother and baby stimulates breastfeeding behavior in the baby. Newborn infants who are immediately placed on their mother's skin have a natural instinct to latch on to the breast and start nursing, typically within one hour of being born. It is thought that immediate SSC provides a form of imprinting that makes subsequent feeding significantly easier. The WHO reports that, in addition to more successful breastfeeding, SSC between a mother and her newborn baby immediately after delivery also reduces crying, improves mother to infant interaction, and keeps baby warm. According to studies quoted by UNICEF, babies have been observed to naturally follow a unique process which leads to a first breastfeed. After birth, babies who are placed skin to skin on their mothers chest will:

Initially babies cry briefly—a very distinctive birth cry
Then, they will enter a stage of relaxation, recovering from the birth
Then the baby will start to wake up
Then begin to move, initially little movements, perhaps of the arms, shoulders, and head
As these movements increase, the baby will actually start to crawl toward the breast
Once the baby has found the breast and therefore the food source, there is a period of rest. Often, this can be mistaken as the baby is not hungry or wanting to feed
After resting, the baby will explore and get familiar with the breast, perhaps by nuzzling, smelling, and licking before attaching

Providing that there are no interruptions, all babies are said to follow this process and it is suggested that trying to rush the process or interruptions such as removing the baby to weigh or measure is counterproductive and may lead to problems at subsequent breastfeeds.
For mothers with low milk supply, increasing SSC is recommended, as it promotes more frequent feeding and stimulates the milk ejection reflex, prompting the body to produce more milk.