Should I seek a lawyer - work from home issue

I work for a company where I am the only female on the helpdesk team in IT. The company has several work from home employees. I now have a medical condition that has arisen in my last trimester of pregnancy. I submitted my Doctor’s note with the request to work from home, And when I first talk to my HR rep and boss, they made me feel like everything was OK. Now today, I noticed all my access had been cut off. I feel as though that even though they could accommodate the request they are denying me or preventing me with no good reason. I am capable of working from home proficiently with the duties of been doing and I want to continue working. Can you help?