Endometriosis
The most likely diagnosis is C. Endometriosis. This patient's presentation of severe dysmenorrhea unrelieved by NSAIDs combined with a history of infertility is the classic clinical picture of endometriosis 1, 2.
Clinical Reasoning
The combination of two key features makes endometriosis the clear diagnosis:
Severe dysmenorrhea refractory to naproxen (NSAID): This represents secondary dysmenorrhea that has progressively worsened over time, which is characteristic of endometriosis rather than primary dysmenorrhea 1.
History of infertility: Approximately 50% of patients with endometriosis present with infertility, and endometriosis affects at least one-third of women with infertility 1, 2, 3.
Why Other Options Are Less Likely
Endometritis (Option A) is excluded because it presents as an acute or chronic infection with fever, abnormal vaginal discharge, and acute pelvic pain—not chronic progressive dysmenorrhea with infertility 2. The clinical picture described lacks infectious symptoms 4.
Leiomyomata/Fibroids (Option B) are less likely because while they can cause dysmenorrhea and contribute to infertility, they more commonly present with heavy menstrual bleeding as the primary complaint rather than severe painful menses 2. Fibroids are focal masses that distort uterine contour, not the diffuse inflammatory process seen here 2, 5.
Pelvic congestion (Option D) is not a recognized primary cause of severe dysmenorrhea with infertility in the medical literature provided and does not fit the classic presentation 4.
Clinical Implications
Diagnosis is clinical: Laparoscopy with histologic confirmation is no longer required before initiating empiric treatment 1, 6.
First-line imaging: Transvaginal ultrasound should be performed, with sensitivity of 82.5% and specificity of 84.6% for detecting endometriosis 1, 2.
Initial treatment: Combined oral contraceptives or progestin-only options are first-line therapies for pain management, even without surgical confirmation 1, 6, 7.
Fertility considerations: The patient should be counseled that endometriosis causes sustained reduction of ovarian reserve through inflammatory mechanisms, and treatment planning should address both pain and fertility goals 8, 9.