Marian F. MacDorman and Fay Menacker of the Centers for Disease Control and Prevention division of vital statistics at the National Center for Health Statistics, and Eugene Declercq of the Boston University School of Public Health, found after a gradual decline from 1990-2004, the percentage of out-of-hospital births increased by 3 percent from 0.87 percent in 2004 to 0.90 percent in 2005-2006.
A similar pattern was found for home births. After a gradual decline from 1990-2004, the percentage of home births increased by 5 percent to 0.59 percent in 2005 and remained steady in 2006.
Compared with the U.S. average, home birth rates were higher for non-Hispanic white women, married women, women age 25 and older and women with several previous children.
Home births were less likely than hospital births to be preterm, low birth weight or multiple deliveries.
The percentage of home births was 74 percent higher in rural counties of less than 100,000 population than in counties with a population size of 100,000 or more. About 61 percent of home births were delivered by midwives, the study said.
Historically, the percentage of out-of-hospital births declined from 44 percent in 1940 to 1 percent in 1969, and has remained about 1 percent for several decades.