http://orb.sfusd.k12.ca.us/forms/HR/FMLA_FAQ_Supervisors.pdf#search=%22fmla%20california%22And this website is excellent. I've provided a link to the page for women's issues.
http://www.workplacefairness.org/guide?attribute%5B%5D=221Taking unpaid time off is not illegal. That's just silly. That would mean all those workers who don't qualify for PTO would be heading for jail every time they took a vacation!
However, you only have the protection of not losing your job/being demoted/keeping benefits under FMLA (12 weeks). The most important thing to look at is what benefits/time off are/are not provided for people with disabilities at your specific company. You should have the same conditions -- no more or less -- as others with disabilities. This is found in Title VII. You're really dealing with federal laws more than state laws here.
One other thing to consider: are you an at-will or contracted employee? If you're at-will, then once you exhaust any FMLA or disability leave, the employer can terminate you fairly easily if they choose.