Preterm birth, which is the leading cause of newborn death in the U.S., has declined in most states and dropped more than 10% in a few, according to an annual “premature-birth report card” released by the March of Dimes on Tuesday.
The data, from 2006 to 2009, are a positive indication that some interventions are meeting with success, but there are still more than half a million babies born too early each year in the U.S. Despite the improvements, the nation still gets a middling grade of C when it comes to its overall track record on preterm birth.
Just one state — Vermont, with a preterm birth rate of 9.3% — warranted an A. Puerto Rico, Mississippi, Alabama and Louisiana all got Fs; in Mississippi, 18% of babies are born early. Nineteen states earned a C, 16 got a B and 11 — plus the District of Columbia — received a D.
The downward trend in preterm birth rates may be modest, but at least it’s headed in the right direction, says March of Dimes President Dr. Jennifer Howse. “This is a very positive finding given that for the past 30 years, the rate of preterm birth has been increasing,” says Howse. “It’s not a lot, and the rate is still too high, but the good news is some things are starting to work.”
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In 2009, the nation’s preliminary preterm birth rate was 12.2%, a drop from 12.8% in 2006. The March of Dimes wants to reduce that to 9.6% by 2020.
The issue of prematurity is considered significant enough to the nation’s public health that U.S. Surgeon General Regina Benjamin will join the March of Dimes on Tuesday to talk about the health consequences of being born ahead of schedule. Preterm infants can face lifelong health problems including intellectual disabilities, cerebral palsy and vision and hearing loss. Births before 37 weeks cost the U.S. more than $26 billion annually, according to the Institute of Medicine.
In many cases, what causes a baby to arrive ahead of her due date is unknown. But in some instances — such as scheduled C-sections or induced deliveries — doctors can influence the outcome. Progesterone shots can prolong pregnancy in some women who have previously given birth to preterm babies. Smoking-cessation programs for pregnant women can also help, as can making sure more pregnant women have health insurance and encouraging them to seek early prenatal care.
Perhaps most promising is the small but growing number of hospitals who are refusing to schedule elective deliveries before 39 weeks because of new research showing that newborns fare better the longer they stay in utero. In June, a study published in Obstetrics & Gynecology found that mortality rates are halved by waiting until at least 39 weeks, rather than 37 weeks, to give birth.
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The report card arrives a couple weeks ahead of the first-ever World Prematurity Day on Nov. 17, with partners in Europe, Africa and Asia. Of 13 million babies born preterm each year throughout the world, one million die. Says Howse: “There is still a good ways to go.”
Bonnie Rochman is a reporter at TIME. Find her on Twitter at @brochman. You can also continue the discussion on TIME‘s Facebook page and on Twitter at @TIME.