Yes this could contribute to worsening of melasma. Peels should never be used without inhibition of tyrosinase. Melasma is a very common cause of skin pigmentation. It can not be completely cured, however effective treatment are possible. This is because your skin is extremely sensitive to UV and even the smallest amount can stimulate your pigment cells to produce colour. The mainstay of treatment is strict UV protection- hats, sunglasses and SPF every 4 hours. This forms the foundation of all treatments.