A 23-year-old woman with primary infertility has mild facial hirsutism and varied menstrual cycles. What is the most likely diagnosis?

The symptoms presented—primary infertility, mild facial hirsutism, and varied menstrual cycles—are characteristic of Polycystic Ovary Syndrome (PCOS), making it the most likely diagnosis in this case.

PCOS is a common endocrine disorder in women of reproductive age, which is often associated with insulin resistance and hyperandrogenism. The varied menstrual cycles suggest anovulation, which is typical in this condition due to hormonal imbalances. Facial hirsutism is another hallmark of hyperandrogenism, which is frequently seen in women with PCOS, resulting from elevated androgen levels.

In contrast, other conditions listed do not align as closely with the combination of symptoms described. Endometriosis usually presents with pain and can cause infertility, but it typically does not feature hirsutism or irregular cycles to the same extent. Non-classical congenital adrenal hyperplasia could explain hirsutism and irregular cycles, but is less common and typically presents with more severe manifestations, alongside a family history of adrenal disorders. Prolactinoma primarily leads to ovulatory dysfunction and galactorrhea, rather than hirsutism or the symptoms linked to hyperandrogenism.

Overall, the combination of infertility, hirsut