Prematurity Senate hearing

July 1, 2010

The nation knows little about why late pre-term births have increased and have driven up the overall preterm birth rate over the last several decades, an expert from CDC told Congress in a recent hearing.

The nation knows little about why late-preterm births have increased and have driven up the overall preterm birth rate over the last several decades, an expert from the Centers for Disease Control and Prevention (CDC) told Congress in a recent hearing.

The preterm birth rate increased 20% between 1990 and 2006, according to the National Center for Health Statistics (NCHS). Although the rate of preterm births fell from 12.8% in 2006 to 12.3% in 2008, it was the first 2-year decline in almost 3 decades, NCHS said in a report issued in May. Another recent NCHS analysis found that in 2005, 37% of all infant deaths could be attributed to preterm-related causes.

The recent congressional hearing before the House Committee on Energy and Commerce Subcommittee on Health was preliminary to possible work on legislation regarding preterm birth and infant death. Among other things, the 2006 Preemies Act, which authorized an expansion of federal work to prevent preterm birth, will be up for reauthorization in 2011. In addition, the subcommittee chair, Rep Frank Pallone Jr (D-NJ), along with Sen Frank Lautenberg (D-NJ), has introduced the Stillbirth and SUID (sudden unexpected infant death) Prevention Education and Awareness Act (HR 3212), aimed at improving data collection and education on the issues.

Catherine Spong, MD, of the National Institute of Child Health and Human Development (NICHD) testified that preterm infants "are at higher risk for sepsis, pneumonia, hypoglycemia, temperature instability, hyperbilirubinemia, kernicterus, feeding difficulties, white matter damage, seizures, and apnea, and for re-hospitalization after initial hospital discharge. Compared to their term counterparts, late preterm infants appear to be at a higher risk for Sudden Infant Death Syndrome (SIDS) and have higher rates of neurological and developmental morbidities during childhood."

Pointing to a range of research at NICHD on preterm birth, Spong, chief of the Pregnancy and Perinatology Branch, noted that studies on the safety and efficacy of using inhaled nitric oxide therapy to treat babies born at less than 34 weeks' gestation have had mixed results. The National Institutes of Health will convene a consensus conference on the issue October 27-29, she said.

Callaghan told the committee that the question of why African-American mothers are more likely to have a preterm birth, even when socioeconomic and other factors are controlled for, is probably one of the "Holy Grails" of perinatal medicine. Spong said NICHD will hold a scientific workshop in August with the goal of identifying factors associated with disparities in infant death, stillbirth, and preterm birth and on designing research plans.

Much of the discussion with the experts at the hearing focused on the question of whether the increased use of labor inductions and cesarean delivery has contributed to the increase in preterm births.

Alan Fleischman, MD, senior vice president of the March of Dimes Foundation, said that the rise in elective induction and cesarean before term is the result of a number of factors, including more interventionist obstetric practice; malaligned incentives of the healthcare and delivery systems; defensive medicine; and using preterm birth for the convenience of either the professionals or the patient.

Callaghan said that the CDC is currently doing a pilot study in 3 metropolitan Atlanta hospitals to identify a group of infants born between 34 and 36 weeks' gestation and to see whether it is possible to identify why the birth occurred by looking at the medical records. He indicated that the agency will also do key informant interviews in an attempt to get more qualitative information by interviewing physicians, nurses, and others.

"This is hard stuff, because this isn't just numbers. It is really getting around qualitative information about what process goes on when decisions are made to deliver prior to term and then how delivery should take place," said Callaghan.

Callaghan also told the committee that the agency's research seems to indicate that many SIDS deaths could be explained. "SIDS means there is no plausible explanation for the cause of death. It is truly unexplained. The more and more that people do death scene investigations on the ground, again, in and around the time the infant death, the more and more people are finding that there might be explanations," he said.

Although an explanation may not do much for the parents' grief, he said, it might offer a chance for prevention for other infants.