Oral contraceptive pills for heavy menstrual bleeding.

BACKGROUND

Menorrhagia (heavy menstrual bleeding) is a benign yet debilitating social and health condition. The widely accepted clinical definition of menorrhagia is blood loss of 80ml or more per period. This figure is derived from population studies that have shown that the average blood loss is between 30 and 40ml, and 90% of women have blood losses of less than 80ml. Excessive menstrual bleeding is the commonest cause of iron deficiency in the United Kingdom affecting 20-25% of the fertile female population. Menorrhagia is a common problem accounting for 12% of all gynaecological referral in the UK. Ranges of medical therapies are prescribed in order to reduce excessive menstrual blood loss, including prostaglandin synthetase inhibitors, antifibrinolytics, the oral contraceptive pill and other hormones. The combined oral contraceptive pill (OCP) is claimed to have a variety of beneficial, inducing a regular shedding of a thinner endometrium and inhibiting ovulation thus having the effect of treating menorrhagia and providing contraception.

OBJECTIVES

To determine whether: 1. the OCP is an effective medical therapy to reduce menorrhagia in both the short term and long term. 2. the effectiveness of combined oral contraceptive pills (OCP) compared with other medical therapies for the treatment of menorrhagia. 3. OCP is a more cost effective method than any other medical treatments of menorrhagia. 4. OCP has fewer side effects than other drugs used for menorrhagia.

SEARCH STRATEGY

All publications which describe randomised trials of OCP for the treatment of menorrhagia were obtained using the search strategy developed by the Menstrual Disorders Group.

SELECTION CRITERIA

All randomised controlled comparisons of OCP versus other medical therapies, placebo or no treatment for the treatment of menorrhagia. Women of reproductive years with regular heavy periods, measured either objectively or subjectively and greater than, or equal to, two months follow up.

DATA COLLECTION AND ANALYSIS

All assessments of the quality of trials and data extraction were performed unblinded by at least two reviewers. Only one trial met the inclusion criteria and none were excluded. The included trial involved a total of 45 women.

MAIN RESULTS

As the trial used a cross-over design, only data from the first treatment period (cycles 3 and 4 ) were analysed. The results from all the three mefanamic acid groups were combined. There was no significant difference in menstrual blood loss (MBL) between those patients treated with the OCP and danazol, mefenamic acid or naproxen.

REVIEWER'S CONCLUSIONS

The one small study identified [Fraser 1991] found no significant difference between groups treated with OCP, mefenamic acid, low dose danazol or naproxen. Overall, the evidence from the one study identified [Fraser 1991] is not sufficient to adequately assess the effectiveness of OCP. This review was unable to achieve its stated objectives because of the paucity of the data.