oligomenorroe

Oligomenorrhea refers to infrequent menstrual periods in which the interval between cycles is extended beyond the typical 21–35 days, most commonly defined as cycle length greater than 35 days, resulting in fewer than about 9 menstrual periods in a year. It is a form of menstrual irregularity that differs from amenorrhea (no menses) and polymenorrhea (frequent menses).

Causes include physiologic states such as adolescence and the transition to menopause, postpartum lactation, and significant weight changes or intense exercise. Pathologic causes common in reproductive-age people include pregnancy and lactational amenorrhea, hypothalamic dysfunction (e.g., stress or weight loss), ovarian disorders such as polycystic ovary syndrome, thyroid disease, and hyperprolactinemia. Medications or long-acting hormonal contraception can also produce irregular, infrequent menses.

Evaluation begins with a detailed history and physical examination, followed by pregnancy testing. Laboratory testing may include thyroid-stimulating hormone, prolactin, androgens as indicated, and assessment of ovulatory function. Pelvic ultrasound can help evaluate for polycystic ovary syndrome or structural causes. The differential diagnosis includes PCOS, hypothalamic amenorrhea, thyroid disease, and other endocrine or ovarian conditions. In adolescents, irregular cycles can be a normal variant in the first years after menarche.

Management targets the underlying cause and patient goals. For those not seeking pregnancy, cycle regulation with combined oral contraceptives or progestin regimens is common. Lifestyle modification is encouraged for weight or activity-related causes, and metformin may be used in PCOS. When fertility is desired, ovulation induction or other targeted therapies are considered after appropriate evaluation. Regular follow-up and bone health assessment may be indicated in prolonged hypoestrogenic states.