WASHINGTON - More than two in five unmarried women without children in the United States - or 42 per cent - would consider having a child on their own without a partner, an Associated Press-WE tv poll of people under 50 finds. That compares to 24 per cent of men.

The poll, which addressed a broad range of issues on changing family structures in the US, tracks with a recent US Census Bureau report that single motherhood is on the rise. It found that of 4.1 million women who'd given birth in 2011, 36 per cent were unmarried at the time of the survey, an increase from 31 per cent in 2005. And among mothers 20 to 24, the percentage was 62 per cent.

The new poll found that few Americans think the growing variety of family arrangements is bad for society.

However, many have some concerns about single mothers, with some two-thirds - or 64 per cent - saying single women having children without a partner is a bad thing for society. More men - 68 per cent - felt that way, compared to 59 per cent of women.

The survey found broad gender gaps in opinion on many issues related to how and when to have children. One example: Women were more apt than men to say having children has negatively impacted their career.

And this was true especially among mothers who waited until age 30 or older to have children. Fully 47 per cent of those mothers said having a child had a negative impact on their careers. Of women overall, 32 per cent of mothers reported a negative effect, compared with 10 per cent of men.

Ms Joyce Chen, a 41-year-old hospital occupational therapist and a single mother, is happy to have work that she enjoys and can balance easily with caring for her 10-year-old daughter. "I've been blessed," she said. "I have a decent income. I don't feel like I need to climb the ladder. I enjoy what I do, but I can leave it at the end of the day and not think about it."

Ms Chen also credited a strong community of friends from church for helping make her family work, and she hopes to get married one day if the right person comes along. But she feels that a single mom can do just as good a job of raising a child as two parents can.

Overall, the poll found mixed results on that question: 30 per cent of respondents said yes, 27 per cent said no, and 43 per cent said "it depends."

At 26, Ms Jacqueline Encinias is at a much less established point in her career. A married mother of a month-old baby, she wants to go back to school to study accounting. She said she probably would not have made the choice to be a mother alone.

"I wouldn't want my child to grow up with just one parent," she said. Support of a partner is crucial to her.

Thirty-seven per cent of women said they'd consider adopting solo, compared to 19 per cent of men. About a third of women - 31 per cent - said they'd consider freezing their eggs, and 27 per cent would be willing to use artificial insemination and donor sperm.

Many respondents said that while the optimal situation for raising kids is two parents, there's no prescription for the perfect family.