Primary amenorrhoea is seen in all except: (Repeat)
**Core Concept**
Primary amenorrhoea refers to the failure to initiate menstruation by the age of 16 years in the presence of normal secondary sexual characteristics, or by the age of 14 years if there is no development of secondary sexual characteristics. This condition can be caused by various factors, including genetic, anatomical, hormonal, and systemic disorders.
**Why the Correct Answer is Right**
The primary cause of primary amenorrhoea is usually related to anatomical abnormalities, such as vaginal agenesis, or hormonal imbalances, including gonadal dysgenesis, androgen insensitivity syndrome, or premature ovarian failure. These conditions disrupt the normal development of the reproductive system, leading to the absence of menstruation. In cases of primary amenorrhoea, the ovaries may be present, but their function is impaired, resulting in elevated gonadotropin levels and an absence of estrogen production.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option may be incorrect, as primary amenorrhoea is not typically seen in women with polycystic ovary syndrome (PCOS), which is usually characterized by irregular menstrual cycles and hyperandrogenism.
* **Option B:** This option is incorrect, as premature ovarian failure is actually a cause of primary amenorrhoea, characterized by the loss of ovarian function before the age of 40.
* **Option C:** This option may be incorrect, as Turner syndrome is a chromosomal disorder that can cause primary amenorrhoea due to ovarian dysgenesis and a lack of estrogen production.
**Clinical Pearl / High-Yield Fact**
It's essential to note that primary amenorrhoea can be a symptom of an underlying chromosomal or genetic disorder, emphasizing the need for a thorough evaluation and diagnostic workup to determine the underlying cause.
**Correct Answer: A.**