(WASHINGTONTIMES) — The percentage of first-born U.S. babies born to a married mother and father has fallen below 60 percent for the first time, the Census Bureau said Tuesday, while more than one in five first-born children are now born to cohabiting parents.

Among young women, norms have flipped: Since 2005, only 24 percent of mothers aged 23 or younger were married when they had their first child. More typically, these young mothers were either cohabiting (38 percent) or not in a defined relationship (38 percent).

In contrast, before 1990, more than 60 percent of first-time young mothers were married.

Researchers focus on women’s marital status because child-bearing outside of marriage is linked to higher risks for poverty, lower educational attainment and family instability, said the new report, written by Census Bureau researchers Lindsay M. Monte and Renee R. Ellis.

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