A 21-year-old woman presents with complaints of primary amenorrhea. Her height is 153 cm, weight is 51 kg. She has well developed breasts. She has no pubic or axillary hair and no hirsutism. Which of the following is the most probable diagnosis?
**Core Concept**
The patient's presentation is suggestive of a disorder of sex development (DSD) or a condition affecting the hypothalamic-pituitary-gonadal (HPG) axis, particularly affecting estrogen production and secondary sexual characteristics.
**Why the Correct Answer is Right**
The patient's well-developed breasts and primary amenorrhea, along with the absence of pubic or axillary hair, suggest a condition where estrogen levels are adequate, but androgen production is insufficient. This is consistent with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, a rare congenital disorder characterized by the absence or underdevelopment of the vagina and uterus, along with normal ovarian function. The patient's height and weight are also within the normal range, which is consistent with the diagnosis.
**Why Each Wrong Option is Incorrect**
**Option A:** Turner syndrome is characterized by short stature, ovarian dysgenesis, and the presence of lymphedema. This does not match the patient's presentation.
**Option B:** Androgen insensitivity syndrome (AIS) is characterized by the presence of testes, absence of pubic and axillary hair, and the presence of breast tissue. However, the patient's presentation is more consistent with a condition affecting estrogen production rather than androgen sensitivity.
**Option C:** Congenital adrenal hyperplasia (CAH) is characterized by an excess of androgens, leading to hirsutism, clitoromegaly, and virilization. This does not match the patient's presentation.
**Clinical Pearl / High-Yield Fact**
In cases of primary amenorrhea, it is essential to investigate the presence of a uterus and ovaries through imaging studies, such as ultrasound or MRI, to determine the underlying cause.
**Correct Answer:** D. MRKH (Mayer-Rokitansky-Küster-Hauser) syndrome.