Hormones that are balanced (meaning: just the normal hormones that your body produces) can affect skin coloring. Why do you think you have a hormonal imbalance?
According to MedlinePlus:
What causes skin darkening, or "hyperpigmentation", is that your skin cells are producing too much melanin. When these cells become damaged or unhealthy, it affects melanin production, and can affect certain parts of your body.
Skin can become darker from sun exposure, certain medical conditions, or pregnancy (again-due to hormones).
What type of dermatologist did you see, and are they Board Certified (of have other credentials)? It is important to know the REASON behind your hyperpigmentation; did you receive this information?