Reproductive · Gynecology
The facts most likely to be tested
Premenstrual syndrome is defined by physical and behavioral symptoms that occur exclusively during the luteal phase of the menstrual cycle and resolve shortly after the onset of menses.
The diagnosis requires a prospective symptom diary documenting symptoms over at least two consecutive menstrual cycles to confirm the cyclic pattern.
Premenstrual dysphoric disorder (PMDD) is the severe form of PMS characterized by prominent irritability, anxiety, and affective lability that significantly interferes with social or occupational functioning.
First-line pharmacologic therapy for moderate to severe PMS or PMDD is the continuous or luteal-phase administration of Selective Serotonin Reuptake Inhibitors (SSRIs).
Combined oral contraceptive pills (COCPs) containing drospirenone are the preferred hormonal treatment for patients who also desire contraception.
Lifestyle modifications including aerobic exercise, stress reduction, and supplementation with calcium carbonate or pyridoxine (Vitamin B6) are recommended as initial management.
Patients must be screened for underlying psychiatric disorders, such as major depressive disorder or generalized anxiety disorder, as these conditions often mimic or exacerbate PMS symptoms.
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A 28-year-old woman presents to the clinic complaining of recurrent mood swings, breast tenderness, and bloating that begin 1 week before her period and resolve within 2 days of bleeding. She reports that these symptoms have caused significant conflict with her coworkers and partner over the last 6 months. She has no history of psychiatric illness, and her physical examination is unremarkable. She keeps a daily log that confirms her symptoms are absent during the follicular phase. Her urine pregnancy test is negative.
What is the most appropriate first-line pharmacologic treatment for this patient?
Selective Serotonin Reuptake Inhibitor (SSRI)
The patient meets the criteria for PMDD/PMS, and SSRIs are the gold-standard first-line pharmacologic intervention for patients with significant functional impairment.
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Etiology / Epidemiology
Occurs in luteal phase of menstrual cycle; affects women of reproductive age with normal ovarian function.
Clinical Manifestations
Cyclic somatic and affective symptoms that resolve within 4 days of menses onset.
Diagnosis
Prospective symptom diary for at least 2 consecutive cycles is required for diagnosis.
Treatment
SSRIs are first-line; do not use if symptoms do not resolve after menses.
Prognosis
Symptoms are chronic but self-limiting at menopause; severe cases may progress to PMDD.
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Epidemiology & Etiology
Affects up to 80% of women, with 5-10% meeting criteria for severe impairment. Risk factors include stress, family history, and low calcium/magnesium intake. It is not caused by abnormal hormone levels, but rather an abnormal response to normal progesterone fluctuations.
Pertinent Anatomy
The hypothalamic-pituitary-ovarian axis regulates the cycle. Symptoms are dependent on the presence of a functional corpus luteum and subsequent withdrawal of progesterone.
Pathophysiology
The primary mechanism involves altered sensitivity to allopregnanolone, a progesterone metabolite that modulates GABA-A receptors. This neurosteroid dysregulation leads to decreased inhibitory neurotransmission in the CNS. The cyclic nature is strictly tied to the luteal phase of the menstrual cycle.
Clinical Manifestations
Patients present with irritability, bloating, breast tenderness, and fatigue. Symptoms must be luteal phase specific and cause functional impairment. Red flags include suicidal ideation or severe depression, which suggest Premenstrual Dysphoric Disorder (PMDD) rather than PMS.
Diagnosis
Diagnosis is clinical, requiring a prospective symptom diary documenting symptoms for 2 consecutive cycles. Symptoms must occur in the 5 days before menses and resolve within 4 days of onset. No specific serum hormone levels are diagnostic.
Treatment
First-line therapy is fluoxetine or other SSRIs, which can be dosed continuously or only during the luteal phase. Contraindications include untreated bipolar disorder or MAOI use. Lifestyle modifications include calcium carbonate supplementation and aerobic exercise.
Prognosis
Symptoms typically persist until menopause. PMDD is the most significant complication, requiring more aggressive psychiatric management. Patients should be monitored for the development of comorbid major depressive disorder.
Differential Diagnosis
Premenstrual Dysphoric Disorder: severe affective symptoms causing marked functional impairment
Major Depressive Disorder: symptoms are constant and not limited to the luteal phase
Perimenopause: associated with irregular cycles and vasomotor symptoms
Hypothyroidism: presents with fatigue and weight gain regardless of cycle timing
Anemia: presents with chronic fatigue and heavy menses