Preterm birth is defined as birth less than 37 weeks of pregnancy. Approximately 50% of preterm births occur spontaneously following the premature onset of labor, while 40% are medically- induced deliveries due to medical conditions endangering the mother and/or fetus and 10% of preterm births are associated with the premature rupture of fetal membranes leading to either a spontaneously or medically-induced delivery. Preterm birth is a serious health problem often under appreciated with respect to its human and financial toll. Approximately 12% of all babies are born premature with 2% of all babies being born very premature. These very premature babies are associated with the highest mortality and morbidity rates. Ten percent of these babies will die. Fifteen percent of these babies with have serious permanent disabilities such as cerebral palsy, mental retardation, deafness or blindness. Fifty percent of these infants will have a moderate learning disability and 7% with have a behavioral problem. Besides its human toll, the financial toll for total hospital stays for preterm births is about $15 billion dollars per year and represents approximately half of all infant hospital stays. Furthermore, the human and economic burden does not end after hospital discharge for those with a disability. Thus, the National Institute of Child Health and Human Development (NICHD) established a specific research network in 2005 to address this important problem.
Funded through 2011, the Genomic and Proteomic Network on Preterm Birth Research uses high-output genomic and proteomic strategies to accelerate knowledge in the mechanisms responsible for premature birth. Approaches, such as genome-wide scans and global serum protein profiling, will be used to identify new biomarkers that increase the risk or are predictive of a preterm delivery and to delineate molecular mechanisms responsible for a preterm birth. Three studies are currently on going:
- The first study is a longitudinal study that will follow 500 women at high risk for a preterm birth (previous spontaneous preterm birth) throughout pregnancy, starting in the first trimester. The primary purpose of this study is to establish a simple test, using either blood, urine or saliva, that can act as a biomarker to predict whether a woman will spontaneously deliver preterm. If successful, this would allow an intervention to be introduced early enough that could prevent the preterm delivery.
- The second study is a case-control matched, genomewide association study that will recruit 1000 women that deliver spontaneously preterm and 1000 women that deliver spontaneously at term. A DNA specimen will be obtained from each woman. The purpose of this study is to determine a DNA profile that increases the possibility of a woman having a spontaneous preterm birth. If successful, this would allow the ability to determine a women’s susceptibility to a preterm birth even before conception. This would also allow the physician to closely monitor the patient and introduce the appropriate intervention based on a particular DNA profile. In addition, DNA from the newborn will also be obtained that may be used in the future to predict the outcome of a preterm infant.
- The third study is an expression profiling study that will recruit 120 women in labor and not in labor for a medically indicated caesarean section resulting in either a preterm or term delivery. Numerous specimens for analysis will be collected. This study is a very detailed global analysis of DNA, RNA and protein expression. A comparison of the analyses between the various groups of women should allow important insight into the molecular mechanisms involved in spontaneous preterm birth.
Ultimately, this research could some day lead to relatively simple screening tests to identify pregnant women (or possibly even women contemplating pregnancy) at risk of a preterm birth and provide them with interventions enabling them to carry a pregnancy to term. Furthermore, the selection of a particular intervention (therapy) may be informed by an individual’s genetic or proteomic profile.
