Pigmentation on cheeks in females OR Melasma, is idiopathic, most of the times. However there are well known causes like pregnancy, oral contraceptive pills, certain pain killers. Sun protection is an essential part of the management of any pigmentation over face.Therefore, a good sunscreen should have broad spectrum UV A coverage in addition to UV B coverage, in order to be able to prevent tanning and it needs to be applied in sufficient quantity and every 2-3 hourly. I don t see sunscreen in your treatment. A sunscreen with minimum 30 SPF would be adequate. It should mention both UV B and UV A coverage. Therefore it is important to select the right sunscreen for desired effects It should be applied in the following quantity: --3ml for face and neck(a little more than 1/2 teaspoon) --3ml for each arm(a little more than 1/2 teaspoon). A sunscreen should be applied every 2-3 hours. You could use a cream contining one or more of the skin lightening agents like kojic acid, hydroquinone, azaleic acid etc, once or twice daily. Besides, you could also opt for chemical peeling sessions from a dermatologist. Chemical peels are very useful for Pigmentation over face. They can be used either alone OR in combination with skin lightening creams. regards