Having one preemie greatly increases the risk for another. Other risk factors include pregnancy before age 17 or over 40, and the mother's own health conditions, such as being underweight or overweight, or having diabetes or high blood pressure. That's why it's so important for women to have good care, not only early in pregnancy, but before they conceive, said the March of Dimes' Christopher Howson.
But all those factors explain only a portion of preterm birth. NIH's Spong pointed to efforts to understand how vaginal infections and inflammation may help trigger preterm labor.
Another mystery: Why African-American women are at higher risk, with a preterm birth rate of about 17 percent compared to under 11 percent among white women, Howson said.
Still, many women don't know that there are some protections, said Nikki Fleming of suburban Charlotte, N.C., who benefited from two of the steps recommended in Thursday's report and tries to spread the word.
Fleming's first baby, Lauren, was born at 26 weeks, weighing just over 2 pounds and spending her first five months in the hospital. Fortunately Lauren, now a healthy 8-year-old, fared well. But Fleming's next pregnancy ended in a miscarriage.
Her doctor determined that she would benefit from that cervical stitch as well as the progesterone shots. The result: two healthy full-term babies.
"I appreciate that they didn't treat it like an isolated incident," Fleming said.
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