Hormonal imbalances can cause acne by two main mechanisms:
- It increases sebum production which contributes to the blockage of pores and comedone formation. Comedones are the earliest lesions of acne.
- It increases inflammation and makes inflammatory acne worse. Inflammatory acne includes painful small and red bumps that may be filled with pus and larger nodules and cysts.
Hormonal imbalances are the main cause of acne in women with polycystic ovary syndrome, or simply PCOS, and is believed to be a key factor causing adult acne in females.
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