Effect of danazol on serum gonadotrophins and steroid hormone concentrations in women with menorrhagia

Heavy menstrual bleeding diagnosis and medical management

Heavy menstrual bleeding (HMB) is a common gynecological problem that has a significant impact on a woman’s quality of life and the activities of daily living. Due to the difficulty in accurately describing menstrual bleeding abnormalities using older terminology, the PALM-COEIN classification system of the Federation Internationale de Gynecologie et d’Obstetrique was proposed to describe and identify the etiology of abnormal endometrial bleeding. As there is no single pathway that is associated with HMB, there are several therapeutic interventions involving different molecular pathways to reduce HMB. This article will highlight the current evidence as it relates to the etiology of HMB as well as medical modalities of treatment.

Danazol for heavy menstrual bleeding

BACKGROUND

Heavy menstrual bleeding (HMB) is an important cause of ill health in pre menopausal women. Medical therapy, with the avoidance of possibly unnecessary surgery is an attractive treatment option, but there is considerable variation in practice and uncertainty about the most effective therapy. Danazol is a synthetic steroid with anti-oestrogenic and anti progestogenic activity, and weak androgenic properties. Danazol suppresses oestrogen and progesterone receptors in the endometrium, leading to endometrial atrophy (thinning of the lining of the uterus) and reduced menstrual loss and to amenorrhoea in some women.

OBJECTIVES

To determine the effectiveness and tolerability of danazol when used for heavy menstrual bleeding in women of reproductive years.

SEARCH STRATEGY

All studies which might describe randomised controlled trials of danazol for the treatment of heavy menstrual bleeding were obtained by electronic searches of MEDLINE, EMBASE, Current Contents, CINAHL, National Research Register and the Menstrual Disorders and Subfertility Group's Specialist Register of controlled trials (on 6 November 2001). Attempts were also made to identify trials from citation lists of included trials and relevant review articles. In most cases the first author of each included trial was contacted for unpublished additional information.

SELECTION CRITERIA

Randomised controlled trials of danazol versus placebo, any other medical (non-surgical) therapy or danazol in different dosages for heavy menstrual bleeding in women of reproductive age with regular HMB measured either subjectively or objectively. Trials that included women with post menopausal bleeding, intermenstrual bleeding and pathological causes of heavy menstrual bleeding were excluded.

DATA COLLECTION AND ANALYSIS

Nine RCTs, with 353 women, were identified that fulfilled the inclusion criteria for this review. Quality assessment and data extraction were performed independently by two reviewers. The main outcomes were menstrual blood loss, the number of women experiencing adverse effects, weight gain, withdrawals due to adverse effects and dysmenorrhoea. If data could not be extracted in a form suitable for meta-analysis, they were presented in a descriptive format.

MAIN RESULTS

Most data were not in a form suitable for meta analysis, and the results are based on a small number of trials, all of which are under-powered. Danazol appears to be more effective than placebo, progestogens, NSAIDs and the OCP at reducing MBL, but confidence intervals were wide. Treatment with danazol caused more adverse events than NSAIDs (OR 7.0; 95% CI 1.7, 28.2) and progestogens (OR 4.05, 95% CI 1.6, 10.2), but this did not appear to affect adherence to treatment. Danazol was shown to significantly lower the duration of menses when compared with NSAIDs (WMD -1.0; 95% CI -1.8, -0.3) and a progesterone releasing IUD (WMD -6.0; 95% CI -7.3, -4.8). There were no randomised trials comparing danazol with tranexamic acid or the levonorgestrel-releasing intrauterine system.

REVIEWER'S CONCLUSIONS

Danazol appears to be an effective treatment for heavy menstrual bleeding compared to other medical treatments, though it is uncertain whether it is acceptable to women. The use of danazol may be limited by its side effect profile, its acceptability to women and the need for continuing treatment. Overall no strong recommendations can be made due to the small number of trials, and the small sample sizes of the included trials.

Danazol in the treatment of menorrhagia: the effect of a 1 month induction dose (200 mg) and 2 month's maintenance therapy (200 mg, 100 mg, 50 mg or placebo)

This paper highlights the difficulties of recruiting subjects to objective menstrual blood loss (MBL) studies. Such difficulties may explain the relative paucity of such studies in the literature. Eleven women with objectively assessed evidence of menorrhagia were treated for 1 month with an induction dose of 200 mg of danazol (Danocrine). Subsequently the women were randomly assigned to receive 50, 100 or 200 mg of danazol or placebo for 2 months of maintenance dosing. Follow-up with objective assessment of MBL was continued for 3 months after cessation of maintenance dosing. Danazol 200 mg as an induction dose significantly reduced MBL. The maintenance dose of 200 mg during the following 2 months produced a further decrease in MBL and in some cases amenorrhoea. The lower maintenance dosages of 50 mg and 100 mg were associated with a variable response. The study was unable to determine whether any beneficial effect of the maintenance dosages of danazol could be maintained following cessation of therapy since the study numbers had become too small. It appears, however, that there is unlikely to be any persisting benefit once therapy has ceased.

A comparative study of danazol and norethisterone in dysfunctional uterine bleeding presenting as menorrhagia

This randomized open study compared the efficacy and safety of norethisterone, 5 mg three times a day from day 19 to 26, and danazol, 200 mg daily, in the treatment of dysfunctional uterine bleeding presenting as menorrhagia. Clinical criteria were employed to confirm the diagnosis, and subjective assessment of the condition was performed during one pre-treatment and three treatment cycles. Fourteen patients commenced norethisterone and 10 danazol. Bleeding intensity scores were significantly lower with danazol than with norethisterone, and patients assessed their blood loss to be significantly less with danazol than with norethisterone. Associated symptoms of backache and abdominal pain were improved to a similar degree by both treatments. Adverse reactions were reported with similar frequency and were of a similar nature in both treatment groups.

Risk-benefit assessment of drugs used for the treatment of menstrual disorders

This article considers the benign yet debilitating conditions of menorrhagia, dysmenorrhoea and irregular menstrual bleeding. Surprisingly little has been reported in the literature concerning these common ailments which can detract from the quality of female life during the reproduction years. Both dysmenorrhoea and menorrhagia are subjective complaints, but despite accurate means of measuring menstrual blood loss such quantification is rarely performed. This lack of diagnostic accuracy is a cause for concern, especially as both medical and surgical treatment are not without risk. The therapeutic alternatives which are commonly prescribed in an attempt to rectify such menstrual disorders are discussed. These include the nonsteroidal anti-inflammatory agents, the combined oral contraceptives, danazol, progestogens, antifibrinolytics, haemostatics, luteinising hormone releasing hormone analogues and clomiphene. The results of clinical trials which have utilised these various agents are considered in terms of both the effectiveness of treatment and its potential adverse effects.

Thermoregulatory and endocrine effects of a low dose of danazol in postmenopausal women: interaction with the effect of naloxone

Before and on the 30th day of danazol administration (200 mg/day), in six postmenopausal women the activity of endogenous opioid peptides has been indirectly evaluated by the effect on LH secretion and body temperature (measured as rectal temperature) exerted by the infusion of the opioid antagonist naloxone (1.6 mg/h x 4 h preceded by 1.6 mg iv bolus). Before and during danazol administration a GnRH test (100 mcg iv bolus) was also performed to evaluate possible variations in pituitary responsiveness to GnRH. Danazol significantly reduced mean plasma levels of LH and FSH (p less than 0.01), and their response to GnRH stimulus (p less than 0.05). Either before or during danazol administration mean plasma LH and FSH levels did not vary during the infusion of naloxone, while body temperature significantly decreased (p less than 0.01). The decrease in body temperature was significantly greater (p less than 0.05) during danazol than before treatment. The present data suggest that in postmenopausal women a low dose of danazol exerts an antigonadotropic effect mainly reducing the pituitary responsiveness to GnRH. The enhanced hypothermic response to naloxone observed during danazol administration also seems to suggest that in postmenopausal women a low dose of danazol enhances the thermoregulatory role of endogenous opioid peptides.

Endocrine consequences of danazol treatment in menorrhagia

In order to study the endocrine side-effects of danazol, 15 patients with severe, benign menorrhagias, were individually treated with this drug to stop bleeding. LH, FSH, testosterone, free testosterone, DES-S, androstenedione, prolactin, estradiol and cortisol serum concentrations were measured before and after the 3 month treatment period. Danazol was found to be effective in reducing the amount of bleeding in patients with benign, severe menorrhagias; however, the weight gain of patients was significant during the 3 month period. LH and estradiol concentrations decreased; testosterone, free testosterone and dehydroepiandrosterone sulfate increased; prolactin, FSH, androstenedione and cortisol serum concentrations did not change, and SHBG disappeared from the serum, during the treatment period. We are of the opinion that danazol is an effective drug in menorrhagias with side-effects. In our view the hyperandrogenicity is the most important side-effect of this substance, which might be the result of some metabolites, but which might be the effect of a peripheral action of the drug as well.

Endocrine effects of danazol in the treatment of endometriosis

The effects of danazol therapy on circulating gonadotrophins, oestradiol and sex hormone-binding globulin (SHBG) binding capacity have been studied in eight patients with endometriosis. There was a significant rise in luteinizing hormone (LH) in the first week of treatment with a fall in oestradiol levels. There was a marked fall in SHBG in the first week which continued up to 4 weeks. It is concluded that danazol is not 'anti-gonadotrophic' as frequently claimed and that its therapeutic actions, side effects and the endocrine changes could be explained by an effect on SHBG production. The rationale of its use in other conditions requires reconsideration.

Peripheral androgen levels in danazol-treated premenopausal women

Eighteen normally menstruating women with endometriosis were treated with 600 mg of danazol daily for 6 months. Blood samples were taken before and after 2, 4, 8, 12, and 16 weeks of treatment and were analyzed for plasma dehydroepiandrosterone sulfate (DHEA-S), dehydroepiandrosterone (DHEA), and testosterone (T) and for serum alanine aminotransferase (ALAT), albumin, creatinine, potassium, and sodium. The basal values of all parameters studied were well within normal reference limits. DHEA-S was significantly increased at 2, 4, and 8 weeks, and DHEA significantly decreased at 8 and 12 weeks of treatment. The ratio between DHEA and DHEA-S was significantly decreased at weeks 4, 8, 12, and 16. T was significantly decreased during the whole period of observation. ALAT was significantly increased at weeks 4, 8, 12, and 16. A slight but significant increase was observed for creatinine and potassium, while no changes were observed for albumin and sodium. Of the two major androgen sources, the adrenal cortex appears to be relatively unaffected; whereas the ovary may be affected to a minor degree. Therefore, it seems likely that the changes observed in DHEA and DHEA-S may be due to minor alterations in renal and hepatic turnover rather than an effect on adrenal steroidogenesis.

Influence of danazol treatment during the luteal phase on pituitary and ovarian function during the subsequent menstrual cycle

Eight subjects with normal menstrual cycles were treated with danazol (800 mg daily) during one luteal phase to assess the effect on follicular development in the subsequent cycle. Plasma levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, and progesterone were measured daily throughout both cycles. Following danazol there was a consistent and significant delay to the preovulatory estradiol (P less than 0.05) and LH (P less than 0.02) peaks and a significant suppression of the early follicular phase FSH (P less than 0.05) and preovulatory estradiol peak plasma levels (P less than 0.05). All other parameters of the post-danazol cycle were indistinguishable from normal. However, there was a small suppression of midluteal phase FSH during danazol treatment, compared with the posttreatment cycle, which was significant for three subjects. It is suggested that the small effect of luteal phase danazol on subsequent follicle development may occur at an intraovarian level through an effect on receptors or enzymes as well as through the small degree of suppression of midluteal phase and early follicular phase FSH.