It is unlawful to discriminate against a job applicant or employee because she is pregnant. However, because you have not worked for the employer at all, you are not eligible for leave under FMLA or PDLL (Pregnancy Disability Leave Law) - which requires at least 1 year of service, over 50 employees, etc. Whether you can qualify for disability benefits is up to the EDD. Check the EDD's website. If you believe your employer is discriminating against you because of your pregnancy or related complications, call an employment law attorney to discuss. If your employer has 5 or more employees, your employer must make efforts to "reasonably accommodate" your condition unless doing so cause an undue hardship.
If your prospective employer has less than five employees, it can basically do anything it wants, including terminating you before you start.
If your prospective employer has five or more employees, then it is not allowed to discriminate against you because you are pregnant, or because you have a disability, and it will be required to work with you to reasonably accommodate your needs unless doing so would cause an undue hardship.
Whether or start on the job or have been accepted to work there but did not actually begin your duties, this above law applies.
Because you presumably will be unable to work, you will not qualify for unemployment insurance. You may be able to get state disability benefits if you would otherwise qualify.
Good luck to you.
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