Review Question - QID 108647

This young patient with painful menses and no signs of other pathologies most likely has primary dysmenorrhea, or menstrual cramping not due to a pathologic cause. Treatment should begin with NSAIDs and possibly combined oral contraceptives.

This patient’s periods were irregular after menarche, likely due to immaturity of the hypothalamic-pituitary-gonadal (HPG) axis. After two years, her cycles became regular and thus likely ovulatory. This tends to be when primary dysmenorrhea begins. The patient’s description of the pain, her normal exam, and the lack of red flag symptoms (unilateral pain, bowel or bladder symptoms, history of pelvic inflammatory disease, etc.) are consistent with this diagnosis. Otherwise, ovarian cysts, endometriosis, fibroids, adenomyosis, or PID could be on the differential. Many of these conditions tend to occur in women 30-40 years old and are therefore unlikely in this patient. Using history and physical exam to exclude such causes of secondary dysmenorrhea is generally sufficient; lab tests and imaging are not indicated in the initial workup. Empiric treatment with NSAIDs, estrogen-progestin OCPs, or both should be tried, with persistent symptoms prompting further evaluation such as laparoscopy or progesterone-containing intrauterine devices. Adolescents typically experience natural improvement in dysmenorrhea and can be trialed off treatment after several years.

Incorrect Answers:
Answer 1: Von Willebrand factor deficiency is a common cause of heavy menstruation, which is classically defined as more than 80 mL of blood loss each cycle. This definition is not practical, and more emphasis is now being placed on how much a woman’s bleeding impinges on her activities. This patient’s quantification and description of her bleeding do not suggest actual menorrhagia, so testing for von Willebrand disease is not indicated. Furthermore, this condition would not cause dysmenorrhea.

Answer 2: Pelvic ultrasound is useful for identifying fibroids, endometriomas, and adenomyosis as causes of secondary dysmenorrhea. However, this patient more likely has primary dysmenorrhea, for which empiric treatment is indicated. If she were to return in 3-6 months with continued symptoms despite NSAIDs and OCPs, ultrasound may be a reasonable option if the exam is tolerable.

Answer 3: MRI of the pelvis is helpful in diagnosing and characterizing causes of secondary dysmenorrhea. As with ultrasound, this imaging is unncessary for this patient’s presentation, which is classic for primary dysmenorrhea. If she were older, had bulk symptoms (urinary or bowel symptoms), or unilateral pain suggesting an ovarian mass, then MRI of the pelvis would be an option.

Answer 5: Increased exercise is thought to have a mildly beneficial effect on dysmenorrhea. However, this patient already plays soccer and is likely physically active. Furthermore, her symptoms are causing significant functional impairment by causing her to miss school, so a more effective and validated treatment is needed.

Bullet Summary:
Primary dysmenorrhea is menstrual cramping without a pathologic cause and often occurs in newly ovulatory young women with increased prostaglandin levels. Physical exam is normal and there are no red flag symptoms such as bowel/bladder changes or unilateral pain, and empiric treatment with NSAIDs or combination OCPs is indicated.