A birth that occurs before the 37th week of gestation
A birth that occurs before the 37th week of pregnancy is considered premature. Although researchers have long sought a way to prevent premature birth, an estimated 9% of infants are still born prematurely, costing the United States billions of dollars in health care expenditures annually. Neonatal intensive care costs for a premature infant generally range from $20,000 to $100,000, and a single day in a neonatal intensive care unit can cost as much as $3,000. While a direct cause cannot be pinpointed for most premature births, there are a number of known risk factors associated with early delivery. These include multiple fetuses, a weak cervix, a difficult pregnancy, fetal abnormalities, maternal infections and other health problems, and poor maternal nutrition. Certain maternal behaviors, including smoking, drug use, and alcohol consumption, are also known to increase the likelihood of premature birth. Physicians often advise pregnant women to avoid prolonged standing or lifting in order to have a better chance of carrying their babies to term.
Measures currently recommended by the medical community to prevent early labor include frequent prenatal check-ups, good nutrition, and adequate patient education and psychosocial support. Medications can often arrest premature labor by acting on the muscle cells of the uterus to suppress contractions. Even if a premature delivery cannot be averted altogether, it can be delayed. A delay of even 48 hours—even in a birth that may be two or three months premature—can make a significant difference. Within this time frame steroids administered to the mother can speed up development of the immature fetal lungs that pose one of the major health risks for the premature infant. This procedure helps most infants between the ages of 26 and 35 weeks and poses no serious risks to either the mother or the baby. If a combination of bed rest and medication can delay delivery of a 25-week-old fetus by even one week, its chances of survival increase 20 percent.
Premature infants have less body fat and thinner skin than full-term babies, and their skull bones are still soft, giving their heads a flattened appearance. (During delivery, their heads are often protected from vaginal compression and decompression by the use of forceps.) Their grasping, sucking, and gag reflexes are not fully developed (often complicating the feeding process), and their fragile central nervous systems tend to make them hypersensitive to sensory stimuli. Often they are unable to respond to more than one type of stimulus at a time—for example, touch and sound—without becoming overloaded. A premature infant's stage of development corresponds more closely to her gestational age rather than to
Many premature infants require special care in a neonatal intensive care unit (NICU), where their heart function, breathing, blood pressure, and body temperature can be closely monitored, and oxygen, ventilators, and tube feeding are available. With the level of care available in these facilities, infants as young as 25 or 26 weeks can be helped to survive. Women who seem likely to deliver prematurely are often moved to hospitals with such units. NICUs have become more comfortable, welcoming places for both infant and parents than they often were in the past. Most infants are still kept in incubators, clear plastic enclosures that are temperature-controlled to accommodate the babies' need for extra warmth. However, bright lights, noise, and other stimuli are kept to a minimum to accommodate the infants' sensitive nervous systems, and they are handled slowly and gently. Parents are still encouraged to interact with their babies, feeding, changing, and holding them. Many NICUs take steps to further personalize the experience for both parents and hospital staff, such as giving the infants little knit hats with their names on them.
Because their internal organs have not finished developing, premature infants face a number of potential health risks, including a greater susceptibility to infection. The smallest infants (those weighing less than 3 lb, 5 oz at birth) are most likely to develop problems. The immature lungs of premature infants pose the most serious danger, especially the threat of respiratory distress syndrome, in which the air sacs cannot function adequately to exchange oxygen and carbon dioxide and may require oxygen and even a ventilator until they become stronger. Apnea, or interrupted breathing, is a common problem among premature infants because the nerve pathways that control breathing are not fully developed. The infants' immature livers also have trouble functioning, often resulting in jaundice and requiring special treatment, and an eye problem called retinopathy of prematurity can cause permanent vision impairment. Neurological conditions such as cerebral palsy are also a danger for premature babies.
Premature birth can cause significant emotional distress for parents. In addition to their concern over the health of the baby, parents (especially the mother) often experience guilt, feeling that there is something they could have done to prevent the early delivery. However, in spite of the connection between prematurity and unhealthy maternal behavior such as smoking and drinking, many premature births occur to mothers who maintain good health habits and are in excellent condition throughout their pregnancies. The majority of premature infants become normal, healthy children and adults, although they do remain small for their ages during their first two or three years. In addition, their incidence of learning disabilities and attention deficit/hyperactivity disorder (ADHD) is higher than that for full-term babies.
Jason, Janine, and Antonia van de Meer. Parenting Your Premature Baby. New York: Delta, 1990.
Lieberman, Adrienne B. The Premie Parents' Handbook: A Lifeline for the New Parents of a Premature Baby. New York: Dutton, 1984.
Pfister, Fred R., and Bernard Griesemer. The Littlest Baby: A Handbook for Parents of Premature Children. Englewood Cliffs, NJ: Prentice-Hall, 1983.
Stirt, Joseph A. Baby. Far Hills, NJ: New Horizon Press, 1992.
International Childbirth Education Association, Inc.
Address: P.O. Box 20048
Minneapolis, MN 55420
Telephone: (612) 854-8660
Maternal and Child Health Bureau
Address: Parklawn Building, Room 18-05
5600 Fishers Lane
Rockville, MD 20857
Telephone: (301) 443-2170
Maternity Center Association
Address: 49 East 92nd Street
New York, NY 10128
Telephone: (212) 369-7300