heartbroken he won't come of steroids

Been ttc for 8 month now we did conceive on but had a miscarriage at 12 weeks. Just found out he's back on them, he knows it's effects he's fertility. I've got a child from another relationship so does he's. I'm heart broken to think he can't wait till i get pregnant to go back on them. He's told me that he's worrys that he's going to loosed he's size if he stays of them. Feel so low what can I do I love him and he's a good father