Role of Stress in Premature Births

123-SA-98

FOR IMMEDIATE RELEASE

STUDY LED BY UC IRVINE RESEARCHER TO EXPLORE ROLE OF STRESS IN PREMATURE BIRTHS

National Institutes of Child Health and Development Provides $2 Million for Study That May Make it Possible to Predict-and Even Prevent-Preterm Births

Irvine, Calif., Oct. 14, 1998 - Many infants born prematurely start their lives in neonatal intensive care units, fighting for survival. They may be hospitalized for weeks, even months, as doctors confront the myriad medical problems that come with preterm birth-and those who survive face a high risk of being disabled for the rest of their lives.

While doctors have the technical knowledge and high-tech tools they need to keep many critically ill premies alive, they don't have any satisfying answers for troubled mothers who ask, "Why did I give birth prematurely?" and "How can I prevent my next child from being born too soon?"

Curt Sandman, a UC Irvine professor of psychiatry and human behavior, and a team of researchers are trying to change that. For more than a decade, Sandman has been conducting research exploring the link between preterm birth and the level of a stress-related peptide called corticotropin-releasing hormone (CRH) in the mother's blood during pregnancy. Sandman and his colleagues at UCI and several other universities recently received a $2 million grant from the National Institutes of Child Health and Development for a five-year study to further examine the association between CRH and prematurity.

Their goal is to find a way to predict, and possibly even prevent, premature births.

Preterm birth, which occurs in about 10 percent of all pregnancies, is associated with 75 percent of all infant deaths, and, by age 2, one-fifth to one-third of preterm children suffer from moderate to severe sensory handicaps, including such disabilities as cerebral palsy, mental retardation, epilepsy, blindness and deafness, Sandman said.

The economic consequences of prematurity are of a magnitude similar to smoking, alcohol abuse and AIDS. As much as 35 percent ($4 billion) of the $11.4 billion spent annually on infant health care in the United States is for costs related to prematurity, and the cost of a stay in neonatal intensive care for a preterm infant ranges from $20,000-$140,000, he added.

"This is a very serious health problem in the United States, but we haven't been able to reduce the rate of preterm birth because the causes remain largely unknown," Sandman said.

Sandman began his research in this area by examining the role of the peptide, or chain of amino acids, called CRH, a hormone released into the bloodstream during periods of intense stress. Other researchers had established that the placenta makes large quantities of CRH and that a rise in the amount of CRH in a woman's bloodstream during pregnancy is part of the normal process of preparing for full-term delivery. Sandman's research has shown that if this rise begins too early in the pregnancy, it may trigger premature delivery.

Sandman also has found that elevated CRH levels in the early third trimester of pregnancy may impair the ability of the human fetus to detect information and may lead to behavioral problems in infancy.

Sandman and his colleagues will attempt to confirm these findings in their current study-their largest to date and possibly the largest ever of its kind with as many as 600 women participating. They also hope the study will determine whether a high level of CRH in the early third trimester of pregnancy actually causes premature birth, or whether it is simply a sign of something else that has gone awry, yet to be identified as a cause of prematurity. The study also is expected to lead to a better understanding of how the placenta is affected by stress, and what role changes in the placenta play in prematurity.

The study participants will be given blood tests measuring CRH levels five times during their pregnancy and once after delivery. They also will complete extensive questionnaires on the sources of psychological stress in their environment and how they are reacting to them.

"It may be that psychological stress experienced early in pregnancy leads to an abnormally rapid rise of CRH that triggers premature birth," Sandman said. "If we can confirm that connection, we may be able to prevent premature births by taking steps to reduce stress during pregnancy, and we may be able to determine who's at risk for giving birth prematurely by doing blood tests to determine whether CRH levels are climbing too quickly."

In order to learn more about how stress might be related to premature birth, the researchers will do a number of tests to examine how study participants react to stress. Study participants will be asked to assess the impact of stresses listed on a "life events scale" including everything from trivial day-to-day problems to life-altering experiences such as a death in the family. They also will be evaluated on a "pregnancy anxiety scale" to determine whether or not those who have the most fear about something going wrong in their pregnancy are at higher risk of giving birth prematurely.

Sandman said the study also will evaluate differences in the way pregnant women in various ethnic groups respond to stress to determine why some groups have higher rates of preterm births than others.

Other UCI researchers involved in Sandman's latest study include: Dr. Manuel Porto, professor and director, maternal/fetal medicine; Dr. Thomas Garite, professor and chair, obstetrics and gynecology; Aleksandra Chicz-DeMet, associate adjunct professor, psychiatry and human behavior, and Laura Glynn, assistant research associate, psychiatry and human behavior. Among those from other universities who are participating: Dr. Calvin Hobel, professor and chair of maternal/fetal medicine at Cedars-Sinai Hospital and UCLA; Christine Dunkel-Scheter, professor of psychology, UCLA, and Dr. Pathik Wadhwa, assistant professor of health psychology, University of Kentucky.

### Contact: Sherry Angel, (949) 824-6925, [email protected]

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