What are Preterm Infants?

A preterm or premature infant is one who is born too soon. An infant is called preterm if he or she is born before 37 weeks of gestation. To be considered full-term, an infant must spend between 37 and 42 weeks in its mother's womb prior to birth. An infant born after 42 weeks of gestation is considered overdue.

Years ago, prematurity was frequently a death sentence. Today, however, the survival rate for preterm infants in the United States, born at 28 weeks, is about 80%. The increased rate of survival is due to major advances in medicine and nursing.

Though advances in medicine have improved the survival rate for preterm infants, many still die. Additionally, many preterm infants are born with health problems. Some of these health problems resolve themselves over time, while others may linger for years.

Often, preterm infants are born with lungs that are not developed enough to function adequately on their own. This can result in severe breathing difficulties at birth. If there is enough warning before the birth of a preterm infant, doctors may give steroids to the expectant mother. Steroids may help the preterm infant's lungs to mature more rapidly.

In addition to lung and breathing difficulties, there are many other problems that may befall preterm infants. Almost any body system may suffer complications when an infant is born too early. Commonly affected organs include the kidneys, liver, and brain. Frequently, preterm infants suffer from gastrointestinal difficulties as well, leading to feeding intolerance.

When preterm labor begins, medical professionals often employ interventions to try to stop or delay it. If these interventions fail or the infant must be delivered to avoid health consequences, plans are usually made to provide the appropriate level of care for both the mother and the baby. Since preterm infants typically require special care, these plans may include transferring the mother-to-be to a facility that has a neonatal intensive care unit (NICU). However, many hospitals have NICUs and such transfers are not always necessary.

Preterm labor may be related to certain diseases and infections. For example, preeclampsia is a condition directly linked to premature labor. Mothers pregnant with more than one fetus, such as twins or triplets, are at increased risk of preterm labor. Smoking, excessive alcohol consumption, and drug abuse are also risk factors for preterm labor. Often, however, the cause is unknown.