Erythema nodosum - gyn causes?

I suffer from recurrent, biopsy-confirmed (by dermatologist) erythema nodosum.  It's my understanding that certain oral contraceptives can cause this - however, I am not taking any!  I have, however, been told that I have ovarian cysts.  I have been experiencing gynecological symptoms, and am wondering if this should be explored as a cause of the erythema nodosum.  Is it possible for ovarian cysts or other gynecological/hormonal problems to cause erythema nodosum?

Please don't simply tell me "ask my gynecologist."  I did - he told me I had an allergic reaction when I had HUGE red lumps on my legs.  I went to the dermatologist for a second opinion.  My gyn is clueless and I'm switching to someone new.  In the meantime, I'd like a dermatological opinion on whether or not gyn causes are possible.