What is the most likely etiology of a woman with infertility and excessive hair growth on her face?

Polycystic ovarian syndrome (PCOS) is the most likely etiology for a woman experiencing infertility and excessive facial hair growth, a condition known as hirsutism. PCOS is characterized by a combination of symptoms that often include irregular menstrual cycles, excessive androgen levels, and the presence of multiple cysts on the ovaries.

The excessive hair growth in PCOS is primarily due to elevated levels of male hormones (androgens), such as testosterone. This hormonal imbalance contributes to various manifestations, including menstrual irregularities and infertility, as the condition can impair ovulation. Additionally, insulin resistance associated with PCOS can further exacerbate androgen production, leading to worsened symptoms.

Infertility in women with PCOS is often a result of irregular ovulation or anovulation, which can significantly impact the chances of conception. Therefore, in the context of the symptoms presented, PCOS stands out as the most plausible cause of both excessive hair growth and infertility in this scenario.