How to get approved for a leave?

So my work is on the verge of firing me because I've been missing a lot of work and been sick.

HR told me to get approved for a leave of absence so that way they can't fire me until I come back.

So last Thursday I was in the hospital because of contractions. I've been having very bad anxiety since I'm so scared of getting fired and I'm so stressed out. The problem is my doctor refuses to put women on leave of absences. Which idk why he cares, it doesn't affect him. I have an important tmrw to determine if he will. And I really don't know what to tell him to convince him.

I can't loose my job because of the benefits.

I'm currently 28 weeks