According to a recently released survey from the United States National Center for Health Statistics, 38.5 percent of all births in the country occur outside of marriage—a historic peak. Of the total number of births to women between the ages of 20 and 29, 60 percent are born to unwed mothers—up 42 percent from 1970.

Statistics also reveal that the number of unwed mothers cohabitating with the birth child’s father has risen. Approximately 20 percent of unwed mothers under age 20 and 13 percent between the ages of 20-24 were living with the father at the time of birth.

Researchers also noticed an increase in the number of unmarried households with biological children, from 200,000 in 1970 to 1.7 million in 2007, the time of the most recent survey.

Another age group with a considerable increase in the number of unwed births were those in their 30s and 40s, which account for one out of every six births.

The survey shows that the more traditional institution of marriage does not seem to be as appealing to younger adults. In 1950, for example, the median age for first marriages was 20 for women and 23 for men. Today those numbers have risen to 25 for women and 27 for men, reflecting society’s changing attitude about marriage and childrearing.