Yes, definitely melasma does have a hormonal effect. That is why it is seen in women during pregnancy or during menopause. Also hormones do play a major important role in melasma. Also it could be hereditary. Increased level of progtsrsone are known to cause melasma. So the increased melasma levels during pregnancy or post menopausal when someone is on hormone medication, that is hormone replacement therapy which contains increased progesterone can lead to melasma. So hormones are known to cause melasma. Vitamin D levels do not majorly affect melasma. Whereas Vitamin D low levels are known to have an effect on eczema, and many other skin conditions, but melasma it is researchwise and theoretically it is known to cause or have any effect on melasma.
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