Paid paternity leave is the exception not the rule in the United States, but a United Kingdom research paper makes a case for dads-only leave.

European experience shows that when parental leave entitlement is available to either the man or the women, it is taken by very few men – less than five per cent. One way of improving father take-up is to have designated 'daddy periods', where a proportion of paid parental leave is set aside exclusively for fathers.

In Norway, four weeks of parental leave is available only to fathers and use of this special father's quota rose to 85 percent in 2000. This policy recognises the needs of both mothers and fathers – as the quota was an extension of parental leave and not subtracted from maternal leave.

In this country, paid paternity leave barely budged over the last ten years, with 16 percent of men at big companies receiving paid leave after the birth of a child this year, up from 13 percent in 1998, according to the New York-based Families and Work Institute. (The change isn't statistically significant, according to the group's report.)