Amenorrhea: Absence of menstrual periods. Primary amenorrhea refers to the absence of menstruation by age 15 without the presence of secondary sexual characteristics, while secondary amenorrhea is the absence of menstruation for three or more cycles or six months in women who previously had regular cycles.

Dysmenorrhea: Painful menstrual periods characterized by severe cramping in the lower abdomen, back pain, and sometimes nausea and vomiting. Primary dysmenorrhea occurs without any underlying medical condition, whereas secondary dysmenorrhea is due to conditions such as endometriosis or fibroids.

Menorrhagia: Excessive menstrual bleeding characterized by prolonged or heavy periods that may interfere with daily activities and lead to anemia. Causes include hormonal imbalances, uterine fibroids, or bleeding disorders.

Oligomenorrhea: Infrequent menstrual periods, with cycles occurring more than 35 days apart. It may indicate hormonal imbalances or conditions affecting ovulation.

Premenstrual Syndrome (PMS): Physical and emotional symptoms that occur in the days leading up to menstruation, such as bloating, mood swings, fatigue, and irritability.