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A number of factors can place a newborn at risk, but being born prematurely or at a low birth weight are significant ones. Saying that an infant is premature or preterm are both ways of saying that the infant was born before a gestational age of 37 weeks (U.S. National Library of Medicine, 2017c). Babies born at full term weighing less than 5 pounds, 8 ounces are considered low birth weight. Babies who are smaller in size than normal for their gestational age are considered small for gestational age. This is an indication that something has restricted physical growth in the prenatal environment. Table 4.3 shows the criteria for identifying different levels of prematurity and low birth weight.

Premature or preterm birth: A birth that occurs before a gestational age of 37 weeks.

Low birth weight: A full-term infant who weighs less than 5 pounds, 8 ounces.

Small for gestational age: Babies who are smaller in size than normal for their gestational age.

Table 4.3

This table shows the criteria used to determine levels of prematurity and low birth weight. Although at times it is important to know how early an infant arrived and at other times it is important to know the infant’s birth weight, these two conditions usually co-occur. Infants who are born early (or preterm) will almost always have a less than normal birth weight.

Sources: Iannelli (2017); Mayo Clinic Staff (2017c).

In 2015, one in every 10 infants born in the United States was a preterm infant (CDC, 2016m). Although the number of preterm births declined between 2007 and 2014, data for 2014 and 2015 have shown a slight increase. Because premature infants are at risk for a number of neurological and development problems, any increase is a cause for concern.

The underlying causes of premature births are complex and not always well understood (CDC, 2016m), but several factors increase the risk. A lack of prenatal care for women who do not have health insurance plays a role in 20% of premature births (March of Dimes, 2013) and the unhealthy maternal behaviors that we have already discussed, such as smoking, drinking, or using drugs while pregnant, are responsible for some premature and low birth weight births. Both the youngest and the oldest mothers also are at increased risk, as are African American mothers (CDC, 2016m). The increase in the number of multiple births in recent years is another factor, because multiples are more likely to be born prematurely. Finally, stress during the pregnancy increases the risk. Over half of women who gave birth to a premature infant identified stress as a contributing factor (Lilliecreutz, Larén, Gunilla, Josefsson, & Sydsjö, 2016).

We have made great strides in recent years in our ability to care for babies born prematurely. Medical technology helps ensure not only their survival but also their healthy development. The modern neonatal intensive care unit (NICU) has roots that reach back more than 100 years. Read Journey of Research: From Child Hatchery to Modern NICU to understand the progress that has been made.

Journey of Research: From Child Hatchery to Modern NICU

One of the first attempts to improve the survival rates of premature infants was an incubator developed by obstetrician Étienne Stéphane Tarnier in the 1880s (Sammons & Lewis, 1985). It consisted of a wooden box with sawdust-filled walls. The box was divided into two compartments. Half of the bottom compartment was left open to allow for circulation of air, and the other half held stone bottles filled with hot water to control the temperature. As the air circulated into the upper compartment, which contained the infant, it passed over a wet sponge to pick up moisture. A chimney in the top compartment allowed the air to pass over the infant and exit into the room (Neonatology on the Web, 2007).

In 1896, Martin A. Couney supervised a display of incubators containing six premature infants at the Berlin World’s Fair, in an exhibit named “Kinderbrutanstalt” or “child hatchery.” The exhibit was such a commercial success (yes, people were willing to pay admission to see these wonders) that Couney repeated it at other expositions around the world until the 1940s (Snow, 1981). The doctor himself did not profit from the admission charges, but rather used the money to cover the cost of the intensive nursing care he provided for the infants. The care was so good that Courney claimed that 6,500 of the 8,000 infants survived, including one as small as 1.5 pounds (Snow, 1981).

By the 1940s, the care of premature infants increasingly moved into the hands of medical specialists, and neonatology was recognized as a medical specialty that deals with newborn infants. Because physicians at that time believed parents were the source of dangerous infections and that premature infants could easily be overstimulated, parents were routinely excluded from the nursery. This practice continued until the early 1970s (Davis, Mohay, & Edwards, 2003), when parents became an important part of the team that cares for a premature infant.

Since then, we have learned that touch and stimulation at a level that is appropriate for the capacity of the premature infant is beneficial, not harmful (Field, Diego, & Hernandez-Reif, 2010). For instance, neonatal massage therapy is associated with weight gain and passive movement of the limbs is associated with both weight gain and increased bone density (Field et al., 2010). While human touch promotes physical well-being in the infant, it also enhances the bond between the parent and the newborn, affirming for the mother the importance of her role in caregiving for her infant (Jefferies & Canadian Paediatric Society, Fetus and Newborn Committee, 2012). Today both parents are encouraged to participate in caring for their infant and to ask questions so they understand the complicated medical interventions that are sustaining their infant. They might even be encouraged to provide kangaroo care, in which the baby is placed in skin-to-skin contact with the parent’s bare chest and draped with a blanket. Low birth weight infants who receive kangaroo care are more likely to survive, have less likelihood of severe illness and infection, and have a shorter stay in the hospital. There also is evidence of improved cardiorespiratory functioning and temperature stability, sleep organization, and neurodevelopmental outcomes (Jefferies & Canadian Paediatric Society, 2012). Our technology has come a long way in its ability to save the lives of very young and fragile infants, but it has not replaced the need for sensitive human interaction.

Care of fragile preterm infants. Hospitals provide intensive medical care for premature infants by carefully controlling their environment and continually monitoring their bodily functions. However, even in this intensive medical environment, human touch is an important part of their care, so parents are encouraged to hold and touch their newborns.

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FANTHOMME Hubert / Contributor via Getty Images

Premature infants cannot regulate their bodily functions in the same way full-term infants can, so the NICU is designed to monitor their functioning and compensate for what they cannot yet do for themselves. For instance, premature infants do not have a layer of body fat that helps them regulate body temperature and fluid loss, so incubators provide constant levels of heat and moisture. They may not yet have a sucking reflex or gag reflex, so they need special feeding procedures. Their immature central nervous system can be easily overwhelmed by stimuli, so the light level is kept low, noise is minimized, and the infants are handled slowly and gently (VanderBerg, 2007). Overall, the staff in the NICU need to be particularly sensitive toward infants who cannot signal what they need (Bowden, Greenberg, & Donaldson, 2000; VanderBerg, 2007).

Modern NICUs are very successful at saving even very small, fragile babies, but as birth weight goes down, the risk of complications goes up. This has created a dilemma for medical professionals who work with these tiny patients. Most NICUs provide intensive care to infants born at a gestational age of 25 weeks or more, but may provide it to infants at a gestational age of 23 or 24 weeks only with the agreement of the parents (Tyson, Nehal, Langer, Green, & Higgins, 2008). The question is whether there is a point at which a premature infant is so small and the chance of survival so low that the humane thing to do is provide comfort care rather than trying to save the life of the infant. Comfort care provides for the basic needs of the infant but stops short of heroic measures that might cause additional pain and suffering without being likely to prolong the infant’s life.

Despite our best efforts, prematurity and low birth weight account for one quarter of all neonatal deaths (March of Dimes, 2015b). Those infants who do survive demonstrate a wide range of developmental outcomes. Some go on to have few, if any, developmental problems and do not differ substantially from full-term infants, while others experience lifelong disabilities that can range from mild to very severe (Serenius et al., 2013). A consistent finding from numerous studies is that low birth weight and premature infants are at increased risk of cognitive impairment and academic failure as they grow up (Jepsen & Martin, 2006). They also can have sensory or motor impairments or be medically fragile, with those who are born the earliest being at greatest risk (Benzies, Magill-Evans, Hayden, & Ballantyne, 2013; Dombrowski, Noonan, & Martin, 2007). However, even among very premature infants born at 22 to 24 weeks of gestation, 20% show no neurodevelopmental impairment (Younge et al., 2017). Many factors—prenatal conditions, birth circumstances, number and quality of medical services utilized by the family, access to intervention services, and many more—come together to affect the quality of the outcome.

T/F #8

An infant who is born prematurely will have developmental problems and lag behind other children of the same age. False

To improve the chances of a good developmental outcome, comprehensive services should start early in development and be delivered consistently over a period of time. Providing psychosocial support and education for the mothers of premature infants results in better outcomes for the infants, but also helps reduce maternal anxiety and depression and increase the parent’s belief in her ability to cope with the situation (Benzies et al., 2013). However, even under the best of circumstances, caring for a premature infant places extraordinary demands on a parent, so parents need to stay motivated to use the services available to them and to follow through on the recommendations made by the professionals who work with their child. The way the parents view their infants and the expectations they have for them are crucial, so it is important that we help parents of premature infants understand that their infants can have good developmental outcomes so they can recognize and appreciate the progress their children make.