Can adrenal insufficiency have anything to do with miscarriages?

Possible: Given than 80% of all primary adrenal insufficiencies are due to autoimmunity (addison's disease), there is a chance that you may harbour other autoimmune diseases (clinically or subclinically) such as type i dm, lupus, or anticardiolipin antibodies syndrome, all of which are known to increases maternal-fetal morbidity including possible miscarriage.

Could: If poorly controlled or if there is another autoimmune problem - as hashimoto's thyroiditis with autoimmune adrenalitis as the cause for addison's.

Definitely: If adrenal insufficiency ( and all other endocrine deficiencies) is not properly replaced and normalized, you can definitely be prone to miscarriage. Discuss w/your endocrinologist.