Role of estrogen, progesterone and prolactin in the etiopathogenesis of melasma in females

Background Melasma is a commonly acquired hypermelanosis of facial skin due to various etiological factors including hormonal imbalance. Objectives To find out the relationship between hormonal imbalance and melasma in females. Patients and methods One hundred and fifty female patients suffering from melasma, between the ages of 17-45 years, were enrolled in the study. They were examined by Wood’s lamp to see the type of melasma whether epidermal, dermal or mixed (dermoepidermal). Patients were investigated for levels of estrogen, progesterone and prolactin in two consecutive follicular and luteal phases on 9 th and 18 th day of cycle, respectively. Forty control cases were also investigated for the aforementioned hormonal levels in their follicular and luteal phases. Results Out of 150 patients, 138 completed the study while 12 patients were lost to follow up. Amongst the 138 evaluable patients, there were only 4 patients who had normal values for all the three hormones i.e. estrogen, progesterone and prolactin in all four phases. Fifteen patients (10.9%) had normal values of estrogen in both follicular (F1 & F2) and luteal phases (L1 & L2) while the remaining 123 patients (89.1%) had deranged values of estrogen (mostly increased) in any of the four phases. The values of progesterone were normal in 62 (44.9%) patients while they were deranged in 76 (55.1%) patients in all four phases. The levels of prolactin were normal in 134 (97.1%) patients while deranged in 4 (2.9%). Out of 40 controls, only 3 (7.5%) had increased values of estrogen in both follicular and luteal phases. Conclusion Estrogen is found to be the causative agent of melasma.