Women who (a) hold plurisexual identities (e.g., bisexual, pansexual) and (b) are male-partnered are understudied. Of interest is how these women construct their sexual identities across the transition to parenthood-a period associated with intensified heteronormative expectations, and changes in women's roles and identities. This longitudinal study of 28 plurisexual, male-partnered women examined women's sexual identity construction across the first year of parenthood, using four waves of data. Most women were White, bisexual-identified, and first-time parents. The majority of women described decreases in the salience or centrality of their sexuality more generally. Almost all women continued to hold plurisexual identities across the first year of parenthood, although many described these as private identities amidst public assumptions of heterosexuality. Some, though, sought to maintain a connection to their plurisexual identities through sexual identity disclosure, same-gender fantasies, and involvement in consensual nonmonogamy. Although only one woman articulated a shift in sexual identity label (from bicurious to heterosexual), others increasingly distanced themselves from their same-gender behaviors and desires. Our findings illustrate how women engage in an active process of sexual identity construction amidst heteronormative pressures, and how they navigate tensions amongst their partnership and parenthood statuses and their private identities and past behaviors.