Differential Diagnosis for Infertility in a 32-year-old Woman
Single most likely diagnosis
- Polycystic Ovary Syndrome (PCOS): This diagnosis is most likely due to the patient's history of irregular menses, difficulty conceiving, and the presence of thick, dark, velvety plaques under her axillae (consistent with acanthosis nigricans, a common finding in PCOS). The bilaterally enlarged ovaries on pelvic examination also support this diagnosis.
Other Likely diagnoses
- Endometriosis: Although not directly indicated by the symptoms, endometriosis is a common cause of infertility and could be considered, especially given the patient's history of multiple sexual partners and potential for pelvic inflammatory disease (PID), which increases the risk of endometriosis.
- Tubal factor infertility: Given the patient's history of multiple sexual partners and inconsistent condom use, the risk of sexually transmitted infections (STIs) and subsequent tubal damage is increased, making tubal factor infertility a possible diagnosis.
- Ovulatory dysfunction: The patient's irregular menses suggest ovulatory dysfunction, which could be a contributing factor to her infertility, independent of or in addition to PCOS.
Do Not Miss diagnoses
- Ovarian tumor: Although the ovaries are described as bilaterally enlarged, which could be consistent with PCOS, it's crucial not to miss the possibility of an ovarian tumor, which could also cause infertility and has significant implications for treatment and prognosis.
- Thyroid dysfunction: Despite the normal TSH level, thyroid dysfunction can sometimes present with normal TSH but abnormal free T4 or free T3 levels, and it is a critical diagnosis not to miss due to its impact on fertility and overall health.
Rare diagnoses
- Congenital adrenal hyperplasia: A rare condition that could present with infertility, irregular menses, and signs of hyperandrogenism, although less likely given the normal LH level and the presence of other more common signs pointing towards PCOS.
- Cushing's syndrome: Although rare, Cushing's syndrome could explain the patient's signs of hyperandrogenism (irregular menses, potential for hirsutism) and infertility, but it would typically be associated with other systemic symptoms and findings not mentioned in the case.