What Does It Mean If a Baby Is Born Preterm?

A premature birth is one that takes place more than 3 weeks before the baby’s estimated due date (at 40 weeks), in other words, before the 37th week of pregnancy. Babies born between 34 and 36 completed weeks of pregnancy are classed as “late preterm”, those born between 32 and 34 weeks as “moderately preterm”, those born at less than 32 weeks as “very preterm” and those born at or before 25 weeks as “extremely preterm”. Premature birth usually means that a baby will need to be cared for in hospital for longer than a baby born at term, with the amount of time influenced by how early he or she is born. Depending on how much care the baby needs, he or she may be admitted to an intermediate-care nursery or a neonatal intensive care unit (NICU).

What Affects Whether a Baby Is Born Preterm?

There are some known risk factors associated with premature birth. These include: the mother having had a previous premature birth, or multiple miscarriages or abortions; an interval of less than 6 months between pregnancies; smoking cigarettes or using illicit drugs; some infections and chronic conditions; stressful life events, physical injury or trauma; and being under- or overweight before pregnancy. However, the specific cause is not often clear and many women who have a premature birth have no known risk factors.

How Can Being Born Prematurely Affect a Baby?

Although some babies born prematurely do not have any complications, generally speaking, the earlier a baby is born the greater the risk. Birth weight also plays an important role. Some complications that may be apparent at birth include breathing, heart and temperature control problems, and babies may also have issues related to metabolism, the blood and the immune system (particularly increased risk of infection). Longer term, they are at increased risk of complications including cerebral palsy, chronic health issues, vision, hearing and behavioural problems, and developmental delay. Because complications at birth can influence the development of longer-term issues, babies admitted to an NICU are closely monitored by the medical team and things such as the baby’s heart rate and oxygenation (oxygen levels inside the body) are frequently checked. They are also at increased risk of developing hypothermia if they have difficulty regulating their body temperature, so are usually cared for in incubators. This helps the baby maintain an optimum temperature and can also protect him or her from noises and direct light, which can cause stress.

What Is Kangaroo Care?

Although incubator care is very effective, kangaroo care is an important component in the care of babies born both prematurely and at term. Kangaroo care is described by the World Health Organization (WHO) as a method of care consisting of putting babies in skin-to-skin contact with their parents. Skin-to-skin contact is known to be effective for thermal control, breastfeeding and bonding, regardless of setting, weight, gestational age and clinical conditions, and is recommended for all newly born babies whether they are born preterm or not. In kangaroo care, the baby wears only a nappy or diaper (and often also a hat), and is placed in a flexed (fetal) position on the parent’s chest. The baby can be secured with a wrap that goes around the naked torso of the parent, ensuring that the baby is properly positioned and supported, or both parent and baby can be covered with a blanket, gown or clothing for warmth. Kangaroo care can even be given if the baby is attached to tubes or wires, as long as the parent stays close to the machines.

What Are the Advantages of Kangaroo Care?

The skin-to-skin contact of kangaroo care provides physiological and psychological warmth and bonding to both the parent and baby. Because the parent’s body temperature is stable, it regulates the temperature of a premature baby more smoothly than an incubator. Babies born preterm that receive kangaroo care also experience more normalized heart and respiratory rates, increased weight gain and fewer hospital-acquired infections. Other benefits include the promotion of frequent breastfeeding, improved sleep/wake cycle and cognitive development, decreased stress levels and positive effects on motor development. There are advantages for the parent as well, with kangaroo care helping to promote attachment and bonding, decrease parental anxiety, improve parental confidence, and promote increased milk production and breastfeeding success. However, to date, studies on the physiological stability of preterm babies during kangaroo care have reported conflicting results.

How Does Kangaroo Care Affect Oxygenation in Premature Babies?

Uncertainties regarding the effects of kangaroo care on oxygen saturation (the oxygen level in the blood) and “regional” cerebral oxygen saturation (i.e. relating to the brain) were investigated through a systematic review of research articles that assessed oxygenation, using pulse oximetry and near-infrared spectroscopy, during kangaroo care in NICUs. Pulse oximetry is non-invasive and pain-free, involves a clip-like device being placed on a body part such as a finger or ear lobe, and uses light to measure how much oxygen is in the blood. Near-infrared spectroscopy is also non-invasive and can continuously monitor regional oxygen saturation. This is important for babies born preterm because early detection of low cerebral oxygen saturation can prevent irreversible cerebral damage that can lead to cerebral palsy.

What Do the Results of the Systematic Review Show?

In total, the results of 25 research articles were analyzed, which documented data for 1,039 premature babies undergoing kangaroo care at three different study points: pre-, during and post-kangaroo care. Although the results of the systematic review cannot be extended to premature babies requiring critical care (described in the review as “unstable”), “stable” premature babies showed no significant differences in heart rate, oxygen saturation in the arteries (blood vessels that carry oxygen-rich blood away from the heart to the tissues of the body) or fractional oxygen extraction (the balance between oxygen supply and demand) compared with routine incubator care. Regional cerebral oxygen saturation also remained stable with a slight upward trend. Although most of the studies included in the review were observational (where participants are simply compared with placebo, no treatment or an alternative condition without randomization) and further studies are needed, the authors conclude that stable preterm babies receiving or not receiving respiratory support are as physiologically stable as those receiving routine incubator care.

Take-Home Message for Parents

Parents of babies born preterm can be reassured that the many benefits of kangaroo care in the NICU do not come at the cost of their baby being adequately oxygenated. Although more research is needed, there is no evidence that premature babies receiving kangaroo care are less physiologically stable than those that receive only routine incubator care.