The rate of out-of-wedlock births has risen so much that if you visit a Pittsburgh maternity ward on Mother's Day, chances are that barely three out of every five moms there nursing a newborn will have a husband.
The U.S. Census Bureau released a report Wednesday estimating that 36 percent of women giving birth in the past year nationally, and 39 percent in the Pittsburgh metropolitan area, were unmarried. The data from the 2011 American Community Survey showed a rise in unmarried pregnancies from 31 percent nationally that was reported in the 2005 survey.
The numbers break down the 4.1 million births that were reported in a 12-month span. The nature of the households those babies joined reflects a long-term trend; the proportion of traditional, nuclear families in the U.S. keeps diminishing.
"The increased share of unmarried recent mothers is one measure of the nation's changing family structure," said Rose Kreider, a family demographer with the Census Bureau. "Non-marital fertility has been climbing steadily since the 1940s and has risen even more markedly in recent years."
Ms. Kreider was a co-author of the report, which emphasized how a pregnant female's young age, low income, lack of education and minority status would all make it more likely that she has no husband when giving birth.
Looking at age alone, 62 percent of women ages 20 to 24 who gave birth in the prior 12 months were single at the time they were surveyed, compared with 17 percent of women ages 35 to 39, according to the 2011 survey data.
Some 57 percent of new mothers with less than a high school diploma were unmarried, compared with 9 percent of college-educated moms.
Among black women covered by the survey, 68 percent were unmarried, compared with 26 percent of non-Hispanic whites. Hispanics who gave birth were single 43 percent of the time, and Asians in 11 percent of the cases.
The report suggested that the overall decline in pregnancies occurring between a husband-and-wife couple is likely affected by the decrease in marriage rates overall, as well as changing social norms regarding sexual behavior.
Homosexual relationships, in which laws prevent marriage in most cases, also more commonly produce offspring than they once did.
While nontraditional households are much more common and widely accepted than they once were, the report observed, "Births outside of marriage are often associated with disadvantage for both children and their parents. Women and men who have children outside of marriage are younger on average, have less education and have lower income than married parents.
"Children who are born to unmarried parents are more likely to live in poverty and to have poor developmental outcomes."
Deena Blumenfeld, owner and lead educator at Shining Light Prenatal Education in Lawrenceville, said she worked in the past with at-risk young women for whom having a baby without a husband added to their financial and emotional worries, but she doesn't see that among the middle-class women she primarily deals with now.
"I would say between a quarter and one-third of my students are not married but are in long-term relationships," in which their partners provide them support equivalent to a husband, Ms. Blumenfeld said. "I wouldn't think it's something that's worrisome or bothersome for them. ... They have the same basic concerns as a married couple about 'How am I going to sleep? Is the baby going to eat enough?' "
She estimated the percentage of expectant mothers she deals with who have no partner at all assisting them with the child would be just 3 to 5 percent.
The report said the share of Pennsylvania's women giving birth while single was at 40 percent, above the national and local average. Johnstown had the highest rate, 48 percent, among metropolitan areas in the state. Lancaster's rate was lowest, at 31 percent.
Gary Rotstein: email@example.com or 412-263-1255.