If being pregnant can put autoimmune in remission is there a medication with the same hormone that can do the same? can this be a treatment?

Autoimmune disease: Autoimmune disease is often less severe during pregnancy, for example with rheumatoid arthritis. It makes sense that if you could chemically simulate pregnancy, you might suppress autoimmune diseases. Unfortunately this isn't feasable as a long term solution and we don't have a perfect model. Prednisone is a steroid immunosuppressant but the side effects of long term use limit its use