For yuri authors that choose to list a gender the vast majority of them, 80%+, are women. While it varies by distributor the audience for yuri works is made up of close to 50/50% men and women.

Furthermore, if you look at the tag numbers on sites like MAL or mangagao you will find that yaoi manga outnumbers yuri manga by more than 5x:

Also, while its male audience has grown in the intervening years, yaoi originated as a genre primarily by and for women who were attracted to men. Bara is generally more written by gay men for gay men.