Help is available for facial brown spots

This is likely due to the increase in estrogen along with the sun exposure.  This is melasma and is difficult to treat, but not impossible.

The least invasive way to treat brown spots is with skin bleachers like hydroquinone.  A relatively new modality is Trilumina, which contains additional agents and is more effective. 

Finally, skin peels like the Vi peel, often in conjunction with microdermabrasion, may be effective. You may need to try several different modalities and several treatments.

Keep out of the sun, use the strongest sun blocks you can get, and wear big brim hats (look for clothing that is rated for sun blocking).