Obstetrics and Gynecology/Menstrual Disorders

Dysmenorrhea Definition Pain on menstruation. Epidemiology Over 70% of women experience dysmenorrhea at some point. Etiology, Risk Factors, and Pathophysiology Primary dysmenorrhea Results from production of prostaglandins within 48 hours of menstruation that stimulates the myometrial cells to contract. Secondary dysmenorrhea The result of a pathologic condition Endometriosis, adenomyosis, cervical stenosis, vaginitis, psychological disturbance Cervicitis Management Birth control pill GnRH analogues NSAIDs (effective in 80% of women) Amenorrhea Definitions Primary amenorrhea: failure to menstruate by 16 years of age with secondary sexual characteristics; failure to menstruate by 14 years of age without sexual characteristics; failure to mensturate with 2 years of sexual maturation. Secondary amenorrhea: failure to menstruate for 6 months with formerly normal menses; oligomenorrhea with less than 9 cycles per year. Etiology, Pathophysiology, and Risk Factors for Amenorrhea Etiologies include Müllerian agenesis (MRKH syndrome) in 10% Androgen insensitivity in 5% Imperforate hymen in 0.1% Transverse vaginal septum in 1/80000 Ashermann's syndrome Enzymatic deficiency Premature ovarian failure Pituitary tumours FSH/LH mutations Pituitary space-occupying lesions Pituitary necrosis Inflammatory/infiltrative pituitary disease Pharmacologic prolactin stimulators Stress induced amenorrhea Isolated gonadotropin deficiency Infections Chronic disease Hypothalamic tumours Adrenal, thyroid, ovarian endocrine disease Metastatic carcinoma Clinical Presentation and Diagnostic Approach Pregnancy must always be excluded. Measure FSH and prolactin If FSH is low or normal Chronic anovulation Anatomic defect (Müllerian agenesis) If FSH is elevated Ovarian failure If prolactin is elevated MRI head for prolactinoma Karyotyping may be performed for the following indications High FSH in a patient under 30 years of age Height <147cm Ambiguous genitalia (congenital adrenal hyperplasia) Absent uterus Management Primary amenorrhea Restore ovulation with estrogen and progesterone Reassurance Secondary amenorrhea Treat the underlying cause