Several Laws Protect Pregnant Workers Injured on the Job

I suffered an on the job injury when I was 32 weeks pregnant. I was ordered out of work by three different doctors. It has now been almost eight months and I continue to be out of work from injury. However, I recently found out that when and if I am cleared to return to work, I do not have a position to return to. Is this legal? And do I have any recourse as far as losing my job after maternity leave and while out on work-related injury? Is this considered discrimination?