I'm not sure, but I'd answer this question the following way:
If you put "the" in "-------- of hormone imbalance", then you have to make sure "disorder" is singular. It will be akin to saying "the town of Oakville", for example.
"the disorder of hormone imbalance" is like a disease.
But, on the other hand, if we say "hormone balance", then "disorders of hormone balance" sounds right without the article, even though I don't exclude the possibility of using it here as well.
I'll wait for native speakers to shed some light on this.
Student or Learner