We analyse Swedish survey data on attitudes about parenthood among young adults aged 22-30 in 1999, and examine who became parents over the next four years. Our results show that while both men and women perceive more benefits to parenthood than costs, men are more likely than women to perceive both negative and positive consequences of parenthood. Further, gender role attitudes shape parental attitudes differentially for men and women. More egalitarian men perceive fewer costs and more egalitarian women perceive fewer benefits than those with more traditional gender role attitudes. Our analyses of the transition to parenthood indicate that, even controlling assessments of the costs and benefits of children, men with more traditional attitudes were more likely to become fathers at an early age, while gender role attitudes had no effect on women’s transition to parenthood. In contrast, there were no gender differentials in the effects of costs and benefits, each of which strongly affected the transition to parenthood, but, of course, in opposite directions. We interpret these findings to indicate that even in a country as far into the Second Demographic Transition as Sweden, negotiating shared parenthood is still sufficiently difficult that it depresses fertility, but now because of its impact on men.