Well, why wouldn't there be?
For me, the most persuasive argument comes from Jane Mansbridge, who wrote a 1999 article in the United States entitled “Should Blacks Represent Blacks and Women Represent Women?” Her answer was “yes”. Her argument was that all of these historically under-represented groups—groups that would have had legal barriers preventing them from participating—should have numbers in their representative institutions that match their demographic weight in the population, precisely because they are diverse groups.
Women are not a monolith. Women are 52% of the population. Of course there is great diversity among women, with any number across the ideological spectrum, across the economic spectrum, and across any kind of policy preference spectrum. The argument I would make is that our deliberative democracy inside parliament would be made better by bringing all of these diverse experiences forward into parliamentary debate. That is the real benefit, for me, in having a gender-equal parliament, for sure.