For superficial marks that haven't yet penetrated into the deeper layers of the dermis, lemon juice is known to lighten marks. Marks caused due to tans and facial hair that needs to be lightened can be bleached with lemon juice. However this remedy seems to work for some and not of the others, for undiagnosed reasons.
These days one finds fancy publicities advertizing drugs and lotions to get rid of birthmarks but you would need to be careful before you pick one up as most of these are not certified and authorized. Natural blemishes on the skin during birth are innocuous but if you are keen on having something erased from your face, it would be a wise decision to get a recommendation of a dermatologist or plastic surgeon from your family doctor.
Birth spots are usually caused by an irregular condensation of melanin in the skin. The presence of concentrated melanin in a particular area is completely harmless although not much is known on why they appear at birth. Birthmarks on the face or exposed limbs may get a bit unnerving, however if you choose to get the right treatment from your medical practitioner and the right outlook towards the discolorations, then your discolorations should not hold you back.
answered by C B