(CBS NEWS) Babies born prematurely carry more health risks than those born after a full pregnancy, including raised risk for intellectual disability, cerebral palsy, breathing problems, digestive woes, and hearing and vision loss.
New research adds heart problems during adulthood to the list.
Adults in their 20s who were born before the 37th week of pregnancy were found to have more problems with the heart's right ventricle, which could reduce the heart's capacity to pump blood.
A typical pregnancy lasts 40 weeks, though recent research suggests pregnancy time may vary up to five weeks from a woman's expected due date.
The researchers behind the new study, published Aug. 12 in Circulation, point out that that up to 10 percent of young adults today are born premature.
"We wanted to understand why this occurs so that we can identify the small group of patients born premature who may need advice from their health care provider about this cardiovascular risk," said study author Paul Leeson, a professor of cardiology at the University of Oxford's Cardiovascular Clinical Research Facility in the U.K., in a press release. "The changes we have found in the right ventricle are quite distinct and intriguing."
The study was funded by the British Heart Foundation.
The human heart contains four chambers: the right and left atria -- which receive and collect blood -- and right and left ventricles, which pump blood from the heart into the circulatory system and rest of the body.
The ventricle on the right side of the heart, specifically, pumps blood from the heart to the lungs, according to the National Heart Lung and Blood Institute.
When breathing air in, a cycle kicks off in which oxygen is passed from the lungs through blood vessels and into the blood. Then, carbon dioxide (waste) is passed from the blood through the lungs where it's removed when you breathe out. The left atrium is what receives this oxygen-rich blood from the lungs, which is then pumped out by the left ventricle into the main artery of the body, the aorta. Then it is delivered to the rest of the body.
The researchers followed a group of premature babies born in the 1980s until they were about 25. They were given standard heart tests checking for blood pressure and cholesterol, in addition to MRI machines to measure patients' blood vessels and heart structures. They then created a computer model to determine how much blood is being pumped in their hearts.
"Their hearts appear to be slightly smaller, they had slightly thicker walls and had a slight reduction of the blood they are pumping," Leeson told CBS News' Alphonso Van Marsh of those born prematurely, when compared to those born at full term.
People with these types of changes in the right ventricle's structure are more likely to have mild to moderate cases of high blood pressure (hypertension), and are at an increased risk for heart failure or cardiovascular-related death, according the researchers.
Previous studies have found similar changes in the left ventricle in adults who had been born prematurely.
But, Leeson insists there's no reason for such adults to panic if they were once a preemie.
"The vast majority will be absolutely fine," says Leeson. But, people born prematurely may represent a group at higher risk that doctors can keep a closer eye on.
The new study "is a great example of how computer models can help identify and analyze an individual's risk," Don Morris, vice president of scientific product technology development at Archimedes Inc., a subsidiary of Kaiser Permanente, said to HealthDay. "This information can be used today to help with better identification of people at risk so they can be treated proactively, for example, by more careful monitoring and control of blood pressure and cholesterol." Morris was not involved in the research.
For mothers trying to reduce their risk of having a premature baby, the Centers for Disease Control and Prevention notes risks include cigarette smoking, alcohol use, chronic health problems in the mother such as diabetes and high blood pressure and having certain infections during pregnancy.
Ryan Jaslow, CBS NEWS