Metrorrhagia, characterized by bleeding episodes without a recognizable cycle, is a frequent form of irregular bleeding in adolescence. Bleeding occurs at different intervals with different durations and differs in amount from spotting to severe. The reason is usually anovulation. The endometrium proliferates under the influence of estrogen until the concentration is relatively insufficient and breakthrough bleeding occurs. The histologic correlate is glandular hyperplasia and the corresponding formation in the ovary is a persistent follicle.

Treatment consists of the administration of an estrogen-gestagen combination (10μg ethinyl estradiol + 5 mg norethisterone acetate, 3 x 1 tablet/day) for 10 days. The estrogen corrects the relative estrogen deficit, thus stopping the bleeding, and the progestagen compound transforms the endometrium.

Two to three days after completion of the 10-day course, the secretory endometrium is shed. The withdrawal bleeding may be severe, in such a case the treatment is as for hypermenorrhea. It is possible that after this bleeding the cycle continues quite regularly, as a kind of rebound effect. Alternatively, to prevent recurrence, treatment can be repeated followed by progestins as for menorrhagia (

table 3).

If there are problems with the above regimens, an oral contraceptive pill will be successful, even in young patients, as a therapeutic approach. Suitable formulations are monophasic micropills with 20 - 35μg ethinyl estradiol and a third-generation progestagen (desogestrel, gestodene, norgestimate). Treatment can be discontinued at any time to observe the further development of the cycle.

A possibility is the administration of the pill continuously without bleeding in an interval to correct anemia and an iron deficit.