ly 75 percent of all infant deaths in the first month of life occur in premature infants (McCormick, 1985). Premature babies often spend months fighting for survival and struggling to overcome illness, and the impact on families is often long-lasting both emotionally and financially. In economic terms, estimates suggest that in the first year of life alone, a preterm birth costs on average about $59,730 (Rogowski, 1998). Furthermore, approximately 35 percent of all expenditures for newborns and approximately 10 percent of all medical expenditures for children are associated with preterm birth (Lewit et al., 1995). Emotionally, the impact on families is harder to quantify but is reputed to be substantial.

Approximately 35 percent of all expenditures for newborns and approximately 10 percent of all medical expenditures for children are associated with premature birth.

WHAT IS PRETERM BIRTH?

The normal length of pregnancy is 40 weeks (plus or minus 2 weeks) as calculated from first day of the woman’s last normal menstrual cycle. A baby born prior to week 37 of gestation is considered premature. However, it is the 1 percent or less of babies who are born at less than 32 weeks and/or who weigh less than 1,000 grams that account for most of the long-term morbidity and mortality observed in premature infants, according to Robert Goldenberg, University of Alabama at Birmingham.

Of all premature babies, approximately 50 percent are born at 35 and 36 weeks of gestation.

Preterm births are classified into two categories: (1) indicated—those deliveries initiated by the clinician for the benefit of either the fetus or the mother, and (2) spontaneous preterm birth—those that follow either spontaneous preterm labor or spontaneous rupture of the membranes. Approximately 20 percent of preterm births are indicated, usually occurring because the mother is severely ill with a life-threatening condition or the fetus shows signs of deterioration and risk of fetal death. Spontaneous preterm labor accounts for the remaining 80 percent. Approximately 30 percent of total preterm births follow spontaneous rupture of the membranes, while the remaining 50 percent follow spontaneous preterm labor, noted Goldenberg. Spontaneous preterm births are often divided into those that occur early and those that occur later. Early preterm births, occurring at less than 30 week’s gestation, generally are associated with an intrauterine infection or placental hemorrhage. Later preterm births, which occur be-

Later preterm babies, which occur between 35 and 36 weeks gestation, are, for the most part, not associated with infection, placental hemorrhage, or a specific etiologic factor.



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