"About four in 10 U.S. births were to unmarried women in each year from 2007 through 2013," the CDC's National Center for Health Statistics reports -- a 14 percent decrease. The most dramatic drops in non-marital birth rates were witnessed among unmarried black and Hispanic women, CDC researchers found.
Birth rates among teens also dropped significantly, suggesting teen pregnancy education and prevention programs may be working.
The report also found that children still being born out of wedlock are increasingly likely to be born into cohabiting unions, couples and parents living together but not married. Children born into cohabiting unions rose from 41 percent of non-marital births in 2002 to 58 percent between 2006 and 2010. The data suggests unmarried couples who chose to have children have more social and financial support than before.
"When people think of non-marital births, they tend to think of single women, but it's really much more likely to be a two-parent cohabitating family," Jennifer Manlove, co-director of the Reproductive Health and Family Formation, recently told NBC News.
Of course, the number of children being born out of wedlock is still high by historical standards. In 2013, 1,605,643 children were birthed by unmarried women. That number was 89,500 in 1940. Of course, ideas about sexuality, marriage and family have changed a lot since then.
More info on childbearing trends and statistics is available on the CDC's website.