NEW YORK » The number of U.S. children being raised by their grandparents rose sharply as the recession began, according to a new analysis of census data. The reasons, while somber, were not all economic.

These grandparents often give themselves high marks as caregivers, but many face distinctive stresses as they confront unanticipated financial burdens and culture shock that come with the responsibilities of child-raising.

In all, roughly 7 million U.S. children live in households that include at least one grandparent, according to a Pew Research Center analysis of the most recent Census Bureau data, from 2008. Of that number, 2.9 million were being raised primarily by their grandparents — up 16 percent from 2000, with a 6 percent surge just from 2007 to 2008.

"Clearly something was going on" in those years, said Pew senior researcher Gretchen Livingston, a co-author of yesterday’s analysis. "We don’t have the data to explicitly state that this is related to recession, but it’s a very educated guess."

Reasons for grandparents taking over child-rearing duties are manifold — often involving a single parent who becomes overwhelmed with financial problems, is incarcerated, succumbs to illness or substance abuse, or dies. High rates of divorce and teen pregnancies fuel the phenomenon, as do long overseas deployments confronting some parents in the military.

"It’s almost inevitable that there is some stress around the reason these grandparents and grandchildren come together," said Donna Butts, executive director of the nonprofit advocacy group Generations United.

"You’re talking about older adults who have agreed to make some sacrifice in their life, and they need to have some support and respect," Butts said. "There are a lot of emotions that the children and the grandparents experience — an anger, a loss of their traditional role."

Roberta Jackson of Winston-Salem, N.C., went through that sort of emotional wringer eight years ago when she agreed to raise her grandson, Drew, who was 6 at the time, after his mother became incapacitated by bipolar disorder.

"When he came to live with me, I had just retired," said Jackson, 63. "I had raised six children of my own, and I wanted to do what I wanted. Drew didn’t want to be with me, and I really didn’t want to be responsible for him."

For several years, Jackson said, Drew proved to be a disciplinary challenge: "The more rules I laid down, the more rebellious he got."

But she enrolled the two of them in counseling sessions, got support from local agencies and sought out a host of activities for Drew, including a Big Brothers Big Sisters program and a youth football league. Drew, who will turn 15 later this month, has improved his grades, and his grandmother hopes he’s on track to go to college.

"We’ve become partners now," she said. "We’ve learned to trust each other."

Jackson is African-American and single. Overall, according to the Pew center, 34 percent of grandparent caregivers are unmarried and 62 percent are women.

The phenomenon of grandparents raising grandchildren has been proportionally higher among blacks and Hispanics than among whites, but the sharpest rise from 2007 to 2008 was among whites, with a 9 percent jump, according to Pew.

In all, 53 percent of the grandparent caregivers are white, 24 percent are black, and 18 percent Hispanic.

According to the Pew Center, most grandparents give themselves high marks for the role they are playing in their grandchildren’s lives — with a majority saying they are doing a very good or excellent job and fewer than 10 percent rating themselves at "fair" or "poor."

The American Academy of Child and Adolescent Psychiatry notes that many children living with grandparents enter that arrangement with pre-existing problems stemming from abuse, neglect, prenatal exposure to drugs and alcohol, and loss of their parents.