New research on the rising trend of delayed marriage in the U.S. reveals some disturbing details for the next generation.

Today, an astonishing 48 percent of first births take place outside marriage. A new study, “Knot Yet: The Benefits and Costs of Delayed Marriage in America,” reveals that the average age of a woman’s first birth (25.7 years) is now lower than the average age at which a woman first marries (27). As a result of this “Great Crossover,” unwed birthrates are higher than ever before.

These trends differ by education level. The vast majority of births to college-educated women still take place within marriage. Childbearing as well as marriage have been delayed for this group.

However, for those with a high school education or less, the concept of marriage and childbearing have become disconnected. For high school dropouts, an astonishing 83 percent of first births are outside marriage. While the majority of unwed births have historically taken place among lower-income women, this trend is now becoming the norm in “middle America,” too. This has been a “rapid and recent” trend, according to the study’s authors. For those with only a high school degree or some college, 58 percent of first births occur outside marriage today.

Although many of those “Middle America” couples who have children outside marriage are living together at the time of their first children’s births, their relationships are much less likely to survive than those of their married counterparts. Nearly 40 percent of 20-something cohabiting parents who had a baby between 2000 and 2005 split up by the time their children were five years old.

Sadly, the Great Crossover creates its own negative economic and cultural “feedback loop,” dimming the chances of upward mobility for the next generation. Without the benefits of an intact family, children are 82 percent more likely to live in poverty and tend to fare worse on a wide range of economic measures. In their teens, they are more likely to engage in high-risk behaviors such as becoming sexually active, engaging in substance abuse, and exhibiting anti-social behavior. They fare worse on emotional and psychological outcomes and have lower levels of academic achievement and educational attainment. Their chances of marrying and starting their own families on a stable foundation are dim. And the cycle continues.

The “Great Crossover” is not just a demographic observation; it’s a clarion call for efforts in the cultural and policy arenas to promote marriage and strong and healthy families.