An article on Real Clear Politics explores the question:

Women do tend to vote for female contenders, but that doesn’t necessarily translate into a gender preference, explains Jennifer Lawless, a political scientist at Brown University who studies women candidates. What happens, she says, is that women are more likely to vote for Democrats, and women candidates are more likely to be Democrats.

Lawless believes that Clinton will actually face challenges in attracting women primary voters. For starters, all the candidates are Democrats, so the party-label advantage goes away.

“Women tend to prefer outside candidates,” Lawless says. “Hillary Clinton is not the outside candidate. She’s the establishment candidate.” Women are also more likely to back liberal candidates. “Clinton’s by far not the most liberal of the bunch.”

That’s not to say that women are totally gender-neutral in placing their votes. All things being equal, they show a slight bias for the woman, Lawless says. But all things are rarely equal