Most respondents to a welfare ministry survey think men should help care for children, and many women with partners who help in raising kids want a bigger family.
According to the Health, Labor and Welfare Ministry survey on family roles, 74 percent of the unmarried male respondents and 86 percent of the single females said both men and women should be responsible for child-rearing.
Many married couples with and without kids agreed.
Of the married couples with kids who do not share parenting duties, 37 percent said they wanted more than two kids, but the figure rose to 44 percent if men helped.
The ministry survey had a response rate of 82 percent and covered 29,000 randomly selected men and women aged 20 to 34.