If your employer assumes that, just because you are a woman, you will be the primary caregiver and can't devote enough time to your job; that because you are pregnant, you won't want to come back to work; that because you are a man granted primary custody of children, you won't be able to handle your job; then you are a victim of sexual stereotyping, which falls within illegal sexual discrimination.
If you need to care for yourself or an immediate family member with regular doctor's appointments, for instance, you are entitled up to twelve weeks a year unpaid leave. This leave can be intermittent. If the employer threatens to terminate you or does terminate you due to needing to miss work for a serious medical condition of a family member, AND they have at least 50 employees, AND you've been there at least a year, you may be protected under the Family and Medical Leave Act. If you know you will need this type of leave, make sure you notify HR in advance so you can be covered.
You can't be fired, not hired, or disciplined because you are pregnant, because of assumptions about the pregnancy and what you'll be able to do, or because of childbirth. If your doctor says you need light duty, then they don't have to give light duty unless they give it for any other temporarily disabled employee. Insurance must cover pregnancy, and benefits for leaves must be the same as non-pregnancy leaves.
For pregnancy or any other serious health condition of yourself or a family member, you can get up to 12 weeks of unpaid leave. While I talked about intermittent leave above, this leave can also be continuous. But twelve weeks and one day of leave will mean that you are no longer protected, and you don't have to be restored to the same or equivalent position. On the other hand, the employer can't use your leave to deny you an open position when you're ready to return.
Florida law protects employees from discrimination on the basis of the fact that they are married or unmarried. The law does not protect you based on being married to a particular person (such as anti-nepotism policies.) However, anti-nepotism policies can't discriminate based on gender.
Harassment based on any of these categories is also illegal. However, you need to report such harassment to HR (I suggest doing it in writing so they can't deny you reported it) and give them a chance to correct the situation. Otherwise, you may be forever barred from suing for the harassment. Make sure you identify the category of illegal harassment you are reporting. General harassment or bullying are NOT illegal.
Once you are demoted, suspended without pay, denied a position or promotion, or terminated based on one of these protected categories, the laws protect you whether or not you report it to the employer first.
Additional resources provided by the author
The best course of action when demoted, denied a promotion, denied a position, suspended without pay, or terminated, particularly where you believe it was because of family responsibilities, is to contact an attorney who handles employment law to discuss your options. You might also check with EEOC, located at eeoc.gov, for more resources on discrimination.