help please advice or success stories

So I have chrons , Psc , anakalosing spondylitis,rheumatoid arthritis I have two children and longing for a 3rd fell quickly with first two (was younger and not having so much wrong at the time ) but struggling with third it's a year of trying feeling low I've had surgery 2years ago and have been told that it becomes harder after and harder when active with an autoimmune diesease need some positivity anyone have more then one problem that contributes to finding it harder to conceive ??