Can between-cycle bleeding be indicative of a serious medical problem?
Dr. Bradley: As long as the patient is not taking oral contraceptives (OCs), mid-cycle bleeding is most likely ovulation bleeding. This type of bleeding is predictable, occurring 10-16 days after the onset of the patient's last menses, light, and lasts 12-72 hours. It occurs in 10%-30% of women and is considered normal, resulting from a sudden surge in estrogen at ovulation that then drops, causing destabilization of the endometrium. The patient need only be reassured that this is a common occurrence and is simply the way her body responds to the hormonal changes associated with her menstrual cycle. Patients who find this normal problem a nuisance may benefit from short-term estrogen supplementation during the periovulatory phase.
Patients who describe a more on-and-off menstrual pattern, in which they have their period for 5 or 6 days and then it stops and starts again a few days later (an irregular trickle), may have a low-grade infection, small polyps, or small intracavity fibroids.
Then, there are patients who bleed like Niagra Falls. This is regular and predictable but consists of excessively heavy bleeds such that clothes are ruined and work and social life become difficult. This pattern suggests a structural abnormality, such as fibroids, polyps, or adenomyosis.
Dr. Schrager: There are two types of mid-cycle bleeding. The first is bleeding that occurs between two otherwise normal periods, called intermenstrual bleeding. The second type is irregular bleeding that does not have a pattern, called metrorrhagia. Heavy bleeding is called menorrhagia, and heavy irregular bleeding is called menometrorrhagia. An important first step in any evaluation of abnormal bleeding is determination of whether the cycles are ovulatory. Premenstrual syndrome, dysmenorrhea, and breast tenderness are three clues to the presence of ovulatory cycles. Intermenstrual bleeding is an ovulatory pattern with mid-cycle spotting. At ovulation, estrogen levels dip temporarily, which is often enough to cause some spotting.
Anovulation is the most common cause of abnormal bleeding in premenopausal women. The most common causes of anovulation are hypothalamic (e.g., stress, excess exercise, eating disorders) and endocrine (e.g., polycystic ovarian syndrome [PCOS], hypothyroidism or hyperthyroidism, hyperprolactinemia). Frequently, no specific cause is identified, and treatment is based on desire for fertility. Many women elect to take OC pills to regulate their cycles and protect against pregnancy. Alternatively, a women desiring pregnancy can take medications to induce ovulation.
PCOS is an important cause of anovulation. PCOS is defined as irregular menses, evidence of hyperandronism (either laboratory or clinical), and absence of other pathology. Many women with PCOS are obese, and weight loss often will restore ovulatory cycles.
© 2004 Mary Ann Liebert, Inc.
Cite this: Toward Optimal Health: The Experts Discuss Abnormal Uterine Bleeding - Medscape - Apr 01, 2004.