Scientists are a step closer to predicting, and one day preventing, preterm births.
Researchers at the University of Utah and Brigham Young University have identified three new biomarkers reduced levels of certain peptides in the blood that signal heightened risk for preterm labor.
Their findings, to be published in the May issue of the American Journal of Obstetrics & Gynecology, suggest up to 80 percent of preterm births could be spotted with a simple blood test taken at 28 weeks into a woman's pregnancy.
Now, the only way doctors gauge a woman's risk for early delivery is if it's happened before, said Sean Esplin, an associate professor of maternal-fetal medicine at the University of Utah and the study's lead author.
"You can test cervical secretions, but that's for women who are already having contractions," said Esplin, who practices obstetrics at Intermountain Healthcare in Murray. "If we could even prolong a pregnancy by one or two weeks, we could make a very big impact on the number of babies that survive and make sure that those that survive are healthy."
More than one in 10 American babies are born prematurely, or before 37 weeks of pregnancy, according to the American Congress of Obstetricians and Gynecologists. It is the leading cause of neonatal mortality in the U.S. and can lead to long-term health problems for the baby, from cerebral palsy to developmental delays.
There are steps doctors can take to prevent premature labor, including bed rest and hormone treatments for the mom. Doctors can also administer corticosteroids to help stabilize and mature the baby's lungs and blood vessels.
"What's been missing is a way of assessing risk," said Steven Graves, who directed the chemistry portion of the research at Brigham Young University.
Graves and Esplin began their search for molecular clues to pregnancy complications in 2002.
Recent technological advances and grants from the Utah Centers for Excellence, Intermountain Medical's Deseret Foundation and a company called Sera Prognostics gave their research a jump-start.
They also had help from a federal National Institutes of Health study that yielded marginal results but a sizeable repository of blood serum samples from 2,292 symptom-free women at 24 and 28 weeks of pregnancy in the early '90s.
Previous studies could look only for known molecules suspected of leading to premature birth, said Esplin.
But using mass spectrometry, Esplin and his team were able to analyze thousands of molecules in the serum of 160 women, looking for anomalies that might suggest risk. Half of them delivered prematurely.
The researchers identified three new peptides that were associated with pre-term deliveries. Women who delivered early had reduced serum levels of the peptides.
When the researchers looked at peptide levels, in combination with proteins that had previously been linked to premature birth, they were able to predict pre-term labor 80 percent of the time.
Michael Varner, an OB-GYN at the U. and board member for the Utah March of Dimes, said the findings will need to be replicated several times before calling them a breakthrough. "But it's certainly very exciting and very encouraging," he said.
The U. and BYU have patented their method for analyzing blood serum and licensed it to Sera Prognostics. The company hopes to have a diagnostic test on the market in the first half of 2012.
Esplin said a confirmation study that is under way with a different population of women is showing promising results.
If the diagnostic test does well in subsequent trials and earns the support of the U.S. Food and Drug Administration, doctors and insurance companies, he said, "we could really have a huge impact in the way we care for pregnant women."