Out-of-wedlock births on the rise worldwide

The percentage of births to unmarried mothers is increasing worldwide, according to a new federal report that shows a universal upward trend over the last 25 years.

Among 14 countries analyzed in the report by the National Center for Health Statistics, the percentage of all live unmarried births in the USA — 40% in 2007 — ranks somewhere in the middle. That's up from 18% in 1980. The sharpest rise was from 2002 to 2007, the report found.

Countries with a higher proportion of births to unmarried mothers include Iceland, Sweden, Norway, France, Denmark and the United Kingdom; countries with a lower percentage than the USA include Ireland, Germany, Canada, Spain, Italy and Japan.

In 2007, the Netherlands had the same percentage as the USA, but it has increased ten-fold there from 4% in 1980.

Demographer Patrick Heuveline of the University of California-Los Angeles found that U.S. mothers are more likely to be single parents because the non-married couple relationship doesn't tend to last very long, something he says continues to be true.

"There might be little bit more cohabitation now, but it's probably true that the United States remains unique and ahead of other countries for births to single mothers not in a cohabiting partnership," he says.

Kelly Musick, an associate professor at Cornell University in Ithaca, N.Y.,says "The relationships of the parents are much less stable in the U.S. than a lot of other countries," . "In Europe, where there are high levels of childbearing outside of marriage, when childbearing is not happening in marriage, it's happening in cohabitation. Cohabitations are reasonably stable."

Other U.S. findings for 2007:

•60% of births to women ages 20-24 were non-marital, up from 52% in 2002.

•Almost one-third (32.2%) of births to women 25-29 were non-marital, up from one-quarter (25.3%) in 2002.

•Births to unmarried women totaled 1.7 million, 26% more than in 2002.