Remedy to lighten or to get rid of dark patches (melasma) on face that developed after pregnancy.

Apply a sunscreen (SPF 20) before going out in the sun.
Use this home remedy to lighten the dark patches:
Mix a little rice powder with curd, and apply it on the affected area daily.
Twice a week: Mix 2 tsps oatmeal, one tsp dry ground lemon or orange peel, one tsp honey and two tsps curd.
Apply the paste on your face, and rinse after 30 minutes.