American men still don't pull their weight when it comes to housework and child care, but collectively they're not the slackers they used to be. The average dad has gradually been getting better about picking himself up off the sofa and pitching in, according to a new report in which a psychologist suggests the payoff for doing more chores could be more sex.

The report, released Thursday by the Council on Contemporary Families, summarizes several recent studies on family dynamics. One found that men's contribution to housework had doubled over the past four decades; another found they tripled the time spent on child care over that span。

"More couples are sharing family tasks than ever before, and the movement toward sharing has been especially significant for full-time dual-earner couples," the report says. "Men and women may not be fully equal yet, but the rules of the game have been profoundly and irreversibly changed."

Some couples have forged partnerships they consider fully equitable。

"We'll both talk about how we're so lucky to have someone who does more than their share," said Mary Melchoir, a fundraiser for the National Organization for Women, who — like her lawyer husband — works full-time while raising 6-year-old triplets。

"He's the one who makes breakfast and folds the laundry," said Melchoir, 47. "I'm the one who fixes things around the house."

Joshua Coleman, a psychologist from San Francisco and author of "The Lazy Husband: How to Get Men to Do More Parenting and Housework," said equitable sharing of housework can lead to a happier marriage and more frequent sex。

"If a guy does housework, it looks to the woman like he really cares about her — he's not treating her like a servant," said Coleman. "And if a woman feels stressed out because the house is a mess and the guy's sitting on the couch while she's vacuuming, that's not going to put her in the mood."

In the U.S., time-use diary studies show that since the '60s, men's contribution to housework doubled from about 15 percent to more than 30 percent of the total. Over the same period, the average working mother reduced her weekly housework load by two hours。

Between 1965 and 2003, men tripled the amount of time they spent on child care. During the same period, women also increased the time spent with their children, suggesting mutual interest in a more hands-on approach to child-raising。

如今，美国男性在做家务和照看孩子方面仍然不够尽职尽责。但总的来说，他们不再像过去那么爱偷懒了。一项最新报告显示，普通男性在分担家务方面的主动性逐渐提高。一位心理学家在报告中提到，男性多做家务能得到更多“性福”。

现代家庭学会于本周四公布了这项报告。该报告总结了几项有关家庭动态的最新研究。其中一项研究发现，在过去四十年中，男性所做的家务量增加了一倍;另一项研究表明，男性照看孩子的时间在这一时期内增加了两倍。

报告指出：“与以前相比，如今有更多的夫妇共同分担家务，而且这一趋势在双职工家庭中尤为明显。可能男性和女性之间仍然没有达到完全的平等，但游戏规则已彻底改变。”

而有些夫妇之间则形成了他们所认为的一种“完全平等”关系。

全国妇女组织的资金筹集人玛丽•梅尔考尔和她的丈夫都是全职律师，他们同时还要抚养六岁的三胞胎。玛丽说：“我们都会感慨自己很幸运，因为我们都尽量多分担一些家务。”

47岁的梅尔考尔说：“他负责做早餐和叠衣服。我负责收拾房间。”

来自旧金山的心理学家、《懒丈夫：如何提高男人做家务和看孩子的积极性》一书的作者约瑟华•科尔曼说，两人平等分担家务有利于婚姻幸福，并能让男性得到更多“性福”。

科尔曼说：“如果丈夫做家务，会让妻子觉得对方真的在乎她——没把她当成佣人。如果妻子看到房间里乱糟糟而感到紧张，但她在打扫房间时，丈夫却若无其事地坐在沙发上，这会影响她的情绪。”

美国的“时间使用日记”调查显示，从上世纪60年代至今，男性所分担的家务活比例翻了一番，从约15%增长至30%多。而在这一时期内，普通职业妈妈每周料理家务的时间则减少了两小时。

从1965年至2003年，男性照看孩子的时间增加了两倍。女性照看孩子的时间在这一时期内也有所增加，这说明父母双方都越来越注重“亲自育儿”。