When it comes to childbirth, sooner is not better than later. According to a new report from the Institute of Medicine of the National Academies, the high rate of premature births in the United States constitutes a public health concern that costs society at least $26 billion a year.

In 2005, 12.5 percent of births in the U.S. were preterm, a 30 percent increase over 1981 rates. Babies born before 32 weeks have the greatest risk of mortality, but "near-term" or "late preterm" infants born between 32 and 36, which makes up the greatest number of preterm births, are still at higher risk for health and developmental problems than full-term newborns.

One mother's tale may be the story of our times. Jenny Minton delivered twin boys prematurely, two months early. For 64 days they struggled, critically ill, in a neonatal intensive care unit. Minton has written "The Early Birds" (Knopf), the story of her harrowing and triumphant quest to bring her sons home. Unfortunately, Minton's experience is no longer rare as half a million children are born prematurely in the U.S. each year.