Up to one-quarter of preterm births might be prevented if women paid attention to three risk factors that are under their control, new research suggests.
Those factors include spacing pregnancies well, beginning at a healthy weight and gaining the recommended amount during the pregnancy, the researchers found.
“These are all risk factors for a really serious health outcome — preterm birth,” said study co-author Dr. Emily DeFranco. She is a researcher at the Center for Prevention of Preterm Birth at Cincinnati Children’s Hospital.
Babies born before 37 weeks’ gestation are considered preterm. Being born early puts babies at risk for breathing, heart, gastrointestinal and developmental problems, among other issues.
In the United States, the overall rate of preterm birth is 11.4 percent — more than twice as high as that in several other developed countries, the researchers said.
Experts have identified many risk factors for preterm birth, so DeFranco’s team looked at some that are manageable to see what role they might play.
The investigators used records of nearly 400,000 births between 2006 and 2011 to examine the three risk factors. None were multiple births.
More than 90 percent of the women had at least one of the three risk factors, the study findings showed.
Only 6 percent had none, providing what researchers called an “ideal” comparison group. Their pregnancies were well spaced, their weight was healthy at the start and the mothers gained no more, or less, than recommended during pregnancy.
These “ideal” women had a preterm birth rate of 7.6 percent, according to DeFranco, who is also an associate professor of maternal-fetal medicine at the University of Cincinnati College of Medicine.
Women who had less than a year between pregnancies as well as those who gained too little weight during pregnancy had higher rates of preterm births, the study authors said.
The highest rate of preterm births — at 25 percent, more than triple that of the ideal group — occurred among women who were underweight when they got pregnant, had shorter gaps between pregnancies and inadequate weight gain during pregnancy, the researchers reported.