American men's contribution to housework has increased about 15 percent in the last 40 years, so has their sex activities, suggested a discussion paper released Thursday.(File Photo)

American men's contribution to housework has increased about 15 percent in the last 40 years, so has their sex activities, suggested a discussion paper released Thursday.

The paper summarizing research on changing family roles prepared for the 11th annual conference of the Council on Contemporary Families in Chicago said that by the early 21st Century, the average full or part-time employed U.S. married woman with children was doing two hours less housework than in 1965. Men's housework load increased from around 15 percent to 30 percent during that time.

The report also found men's contributions to family work increases over time -- the longer their female partners have been in paid employment, the more family work they are likely to do.

Research by psychologist Joshua Coleman said wives report greater feelings of sexual interest and affection for husbands who participate in housework.

The most dramatic increase in men's contributions has been to childcare. From 1965 to 2003, men tripled the amount of time they spent in childcare. However, during this same period women doubled the time they spent in childcare and interaction, the report said.

This mutual increase appears to be related to higher standards by both mothers and fathers about spending time with children.

(Xinhua/Agencies March 7, 2008)