Researchers at Kansas State University found that although interacting more is seen to have a positive impact on the child, there is also a long-term benefit for the mother.

"The most important thing we found was the best way to reduce parenting stress, when parents feel overwhelmed, was to spend more time with their children," said Blake Berryhill, one of the researchers who conducted the study.

She added that being a single mother may bring extra stress, because of decreased economic resources, longer work hours and a limited support network.

Nearly 10 million single mothers were living with children younger than 18 in 2010, up from 3.4 million in 1970, according to U.S. Census figures, which also showed that about 39 percent of births in 2010 were to single, separated or divorced women.

Berryhill and her colleagues based their findings on national data related to single mothers. They also surveyed 2,370 single mothers, studied parental stress and engagement and child temperament at ages one, three and five.

The child's temperament was an important factor, the researchers said, because the more difficult children were when they were young, the less likely the mother would engage with them.

Temperament was also connected to stress because if the mother thought the child was difficult, her level of stress rose.

The study showed that single mothers who spent time engaging with their child at one year old were more likely to continue to engage with their child at age five.

"Being a single mother and being a parent in general is very exhausting, but if a mother is willing to spend time with her children, it can reduce her parental stress because she will feel that in her role as a mom, she is doing an adequate job," Berryhill added.

(Reporting By Joseph O'Leary; editing by Patricia Reaney)

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