Why Do Birth Control Pills Cause Melasma?
Hormones, particularly estrogen, are one of the main triggers of melasma. High estrogen levels in the body may stimulate the production of pigment. Birth control pills work by increasing the level of this hormone. That’s why melasma is a common side effect in people who choose this birth control option. More specifically, estrogen lead to melasma in different ways:
– It has a direct effect on melanocytes, which results in more pigment production.
– It enhances the expression of a gene called PDZK1, which increases the amount of the pigment-forming enzyme tyrosinase.
– It enhances the number of melanocortin receptors in the melanocytes, which make them more sensitive to inflammation or sun.
In addition to estrogen, another ingredient in birth control pills that can trigger melasma is progesterone. [3]
