Differential Diagnosis for Pelvic Pain and Irregular Menstruation

The patient's symptoms of pelvic pain, irregular menstruation, and pain with sexual intercourse can be caused by various conditions. Here's a categorized differential diagnosis:

• Single most likely diagnosis

  • Endometriosis: This condition is characterized by the growth of endometrial tissue outside the uterus, leading to pelvic pain, irregular menstruation, and dyspareunia (pain with sexual intercourse). The patient's symptoms align closely with the typical presentation of endometriosis.

• Other Likely diagnoses

  • Pelvic Inflammatory Disease (PID): PID can cause pelvic pain, irregular menstrual bleeding, and dyspareunia. It is often associated with sexually transmitted infections.
  • Uterine Fibroids: These benign tumors can cause pelvic pain, heavy or irregular menstrual bleeding, and dyspareunia due to pressure on surrounding structures.
  • Adenomyosis: This condition, where endometrial tissue grows into the uterine wall, can lead to pelvic pain, heavy or irregular menstrual bleeding, and dyspareunia.

• Do Not Miss diagnoses

  • Ectopic Pregnancy: Although less likely given the patient's age and presentation, an ectopic pregnancy can cause pelvic pain and irregular vaginal bleeding. It is a medical emergency that requires immediate attention.
  • Ovarian Torsion: This condition involves the twisting of an ovary, which can cause severe pelvic pain. It is a surgical emergency.
  • Appendicitis: While appendicitis typically presents with abdominal pain, it can sometimes cause pelvic pain if the appendix is located near the pelvic organs.

• Rare diagnoses

  • Ovarian Cancer: Although rare in a 37-year-old woman, ovarian cancer can cause pelvic pain, irregular vaginal bleeding, and dyspareunia.
  • Interstitial Cystitis: This condition, also known as bladder pain syndrome, can cause chronic pelvic pain, often accompanied by urinary frequency and urgency.