It's Time to Stem Tide of Premature Births

Infant mortality and long-term health and developmental disabilities are just part of the huge costs to society.

One in every eight infants born in the United States is born preterm -- before 37 completed weeks of gestation. Preterm birth and its consequences are a major health problem in the United States and worldwide, with societal costs in the United States exceeding $26 billion (2005 dollars) annually and $51,500 per preterm infant.

The causes of preterm labor, however, are not fully understood, and in 40 percent of preterm births the exact cause is unknown. Meanwhile, the problem continues to grow: The percentage of preterm births in the U.S. has climbed 36 percent since 1984.

Prenatal conditions that may prompt the delivery of an infant before gestation is complete include pregnancy-induced high blood pressure, fetal distress and inadequate fetal growth. Maternal characteristics also appear to play a role. Women younger than 18 or older than 35 years, women of low socioeconomic status, African-American women and unmarried women are at increased risk for premature birth. At the Regional Medical Center at Memphis, most women who deliver prematurely have several of these characteristics.

A mother's health and reproductive history also can indicate that she is at risk for preterm birth and/or low birth weight (less than 2,500 grams or 5.51 pounds). Among these factors are birth defects, previous preterm births, being underweight before pregnancy, a short time between pregnancies and poor prenatal care. Still another group of risks involves social, psychological and lifestyle factors: Smoking, illicit drug use, domestic violence, lack of social support and high levels of stress have each been implicated in prematurity and low birth weight. Some studies have suggested that the stress associated with lifelong racial discrimination experienced by African-American women may, in part, explain the increased risk of preterm births in this population.

Preterm infants are vulnerable to health problems and are at increased risk for long-term developmental disabilities. Risks are highest for the most premature babies. Extremely premature infants (less than 28 weeks of gestation) require prolonged ventilator and oxygen support, and have increased risk of infections, intestinal complications, retinal damage and brain hemorrhages.

Preterm birth can have severe effects on early brain development. At 34 weeks gestation, a preterm baby's brain is only 65 percent of the weight it would be at term. In addition, his or her brain has formed fewer of the connections between nerve cells that allow it to send, receive and store information. These structural differences, along with health problems during the neonatal period, often result in neurodevelopmental disabilities.

Children who were born preterm have increased risk of cerebral palsy, cognitive deficits and problems at school. Those who were extremely premature tend to trail their peers in social competence and behavior. Even late preterm infants are slower, on average, in achieving infant milestones, and have more learning disabilities than term infants.

Preterm birth, low birth weight and birth defects are the leading causes of infant mortality -- the death of an infant before his or her first birthday. In 2005, the U.S. infant mortality rate ranked 30th in the world, behind most other developed countries. The primary reason for our high infant mortality rate is our higher percentage of preterm births. Reducing preterm births is crucial to reducing the infant mortality rate.

On a positive note, as many as 50 to 75 percent of children born extremely preterm survive and remain free of major disabilities like cerebral palsy and mental retardation. Although advances in perinatal and neonatal care have improved survival rates and reduced the prevalence of severe impairments, many children born prematurely have developmental problems that require special services.

Despite significant improvements in the viability of preterm infants, minimal progress has been achieved in understanding and preventing preterm birth. For instance, racial disparities in preterm birth and infant mortality remain high. We need to increase the socioeconomic well-being and education levels of young men and women in high-risk groups. That translates into improving the environment in which these young people are growing up. We also need to provide easy access to early prenatal care and even pre-pregnancy care for women to optimize pregnancy and neonatal outcomes. Children are our future and all of us must invest in it.

This is one in a series of monthly guest columns on the importance of public/private investment in early childhood. For more information, call The Urban Child Institute at 385-4233 or visit theurbanchildinstitute.org.

Ramasubbareddy Dhanireddy is the Sheldon Bernarr Korones Endowed Professor and chief of neonatology at the University of Tennessee Health Science Center. He also is medical director of the Newborn Center at the Regional Medical Center at Memphis and the Neonatal Intensive Care Unit at Le Bonheur Children's Hospital.

Originally appeared in The Commercial Appeal at http://www.commercialappeal.com/news/2010/nov/13/guest-column-its-time-to-stem-tide-of-premature/