There can be different reasons for dark spots on the face. The most common cause is sun damage. Brown spots from sun damage usually appear on areas of the skin that are naturally exposed to the sun, such as the face and the back of the neck and arms. The best way to prevent dark spots from sun damage is to use sunscreen with UVA protection and limit your time in direct sunlight.
Rarely, the hormones in birth control pills as well as pregnancy have an effect on the pigment in skin. They can cause existing brown spots to darken or cause new ones. This skin condition is called melasma. If this happens, talk to your health care provider about options for birth control.
Rarely, brown spots can be skin cancer, so it’s always important tell your primary care provider or dermatologist (skin doctor) if you notice any changes with your skin.