Primary dysmenorrhea is a common problem in menstruating women, starts at menarche and typically affects adolescents. It is characterized by pain in the lower abdomen or the pelvis region, beginning prior to the onset or during menstruation without any predisposing underlying conditions like endometriosis. A detailed history and findings on physical examination are sufficient to confirm the diagnosis.
Dysmenorrhea is defined as painful menstruation. It can be either primary or secondary. Primary dysmenorrhea occurs in the absence of any identifiable causes such as endometriosis. It affects approximately 90% of menstruating women  and begins within a few months to a year after the onset of menarche . Patients present with pelvic or lower abdominal spasmodic type of pain with or without radiation to the lower limbs or back at the beginning of menstruation          . The pain can last from a few hours to up to four days and is often accompanied by a lower back pain, headache, nausea, vomiting, diarrhea, malaise, and fatigue . This affects the quality of life and can interfere with daily activities like school, studies or work in approximately 5% of the affected females. Severe symptoms are noticed in patients with early onset of menarche, heavy menstrual bleeding, and the habit of smoking. The typical signs usually diminish as age advances and following pregnancy. There is no family history associated with this disorder.
Primary dysmenorrhea can be distinguished from secondary dysmenorrhea by the following features:
The diagnosis of primary dysmenorrhea depends on a detailed history and physical examination . During the collection of anamnestic data, the physician should inquire about the onset, duration, progress and type of menstrual pain along with factors which aggravate or relieve the pain. A history of spasmodic, abdominal or pelvic cramps accompanying menstruation is typical of primary dysmenorrhea while a positive family history in first-degree relatives may be suggestive of endometriosis with secondary dysmenorrhea . A thorough menstrual history should also be recorded. The physical examination, including pelvic and rectal examination, does not reveal any abnormalities in primary dysmenorrhea but it is essential to exclude secondary causes such as tumors or ovarian cysts. In adolescents who are sexually active, a pelvic examination should be performed to rule out pelvic inflammatory disease and a pregnancy test is also warranted. However, it should not be performed in adolescents with suspected primary dysmenorrhea who do not report a vaginal intercourse in the sexual history .
A trial of non-steroidal anti-inflammatory drugs (NSAIDs) with partial relief of pain is used to confirm the diagnosis of primary dysmenorrhea . Failure to respond to the NSAIDs mandates further investigation with laparoscopy, laboratory tests and imaging studies . Otherwise, no further evaluation is required in cases of primary dysmenorrhea.