270 Obstetrics and Gynecology Board Review •••
❍ Name the pathway through which prostaglandins are released.
Cyclooxygenase pathway.
❍ What compound is responsible for dysmenorrhea?
Prostaglandins F.
❍ Name another pathway that is not blocked by nonsteroidal anti-inflammatory drugs (NSAIDs) and
produces leukotrienes.
The lipoxygenase pathway.
❍ In primary dysmenorrhea, when is the typical onset in relation to the menstrual cycle?
The pain usually begins a few hours prior to or just after the onset of menses. The pain may last as long as
48 to 72 hours.
❍ Describe the nature of the pain.
It is colicky, with suprapubic cramping that may or may not be accompanied by back pain, nausea, vomiting, and
diarrhea.
❍ How it is diagnosed?
It is generally a diagnosis of exclusion, once underlying pathology has been excluded. There are no physical,
laboratory, or imaging tests for primary dysmenorrhea.
❍ What is the treatment of choice?
Prostaglandin synthase inhibitors (ie, NSAIDs).
❍ How should they be taken?
Take the inhibitors just prior to or at the onset of pain and then continuously every 6 to 8 hours to prevent
reformation of prostaglandin by-products.
❍ In what percentage of cases are prostaglandin inhibitors effective treatment?
80%.
❍ Name a form of treatment that acts by decreasing endometrial proliferation, thus decreasing the production
of prostaglandins.
Birth control pills.
❍ What percentage of women with primary dysmenorrhea will have relief with birth control pills?
90%.
❍ What other pharmacological agents may improve dysmenorrhea?
Progestin therapies (pill, implant, depot, or intrauterine device), glyceryl trinitrate, magnesium, Ca antagonists,
vitamin B, vitamin E, fish oil, and herbs.