Contraceptives for the management of endometriosis pain

Are OCP's effective for the management of endometriosis pain?

Key Points

Highlights:

• Three studies that either compared combined oral contraceptive pill versus placebo or other medical treatment found low-quality evidence supporting the claim that the OCP use significantly decreases dysmenorrhea. 

Importance:

• The effectiveness of the use of oral contraceptives (OCPs) for pain management in endometriosis has not been clearly analyzed by randomized control studies

Key Results:

• This metanalysis included three studies that were used to assess OCP use in the management of dysmenorrhea for women with endometriosis. 
• For the studies that assessed combined oral contraceptive pill versus placebo, the authors of this paper found that the evidence included in those studies had a high risk of bias and that the rating scale used to report improvement in dysmenorrhea may have skewed results.
• Another study comparing OCP with another medical treatment Goserelin (Gonadotropin-releasing hormone receptor agonist) found that the evidence was of low quality and did not present a clear difference between either treatment option.

What’s done here? 

• This review paper aims to analyze studies that have been done to see if OCP use significantly decreased menstrual-related pain in women with endometriosis.

Limitations:

• This article reviews and analyzes past studies. 

Lay Summary

Endometriosis is a common gynecologic disease that affects many women of reproductive age and is associated with significant morbidity. One of the treatment options for women with endometriosis is the use of oral contraceptives (OCPs) for pain management. However, its effectiveness has not been clearly presented in randomized control studies. 

This article titled, "Oral contraceptives for pain associated with endometriosis" by Brown et al. published in the "Cochrane Database of Systematic Reviews" aims to determine if there is any significant benefit in using OCPs for endometriosis pain management. Authors first searched randomized control studies using the Cochrane CENTRAL Register of Studies Online (CRSO), MEDLINE, Embase, and others to include in the review. In total, three studies that included 404 women with surgically-proven endometriosis were used to compare self-reported pain (dysmenorrhea) with the use of OCPs.

Combined oral contraceptive pill versus placebo

Two studies were included that looked at combined OCP use versus placebo for the control of endometriosis pain. Because both of these studies relied upon self-reported pain, the quality of evidence of the studies was low. Treatment with the combined OCP was associated with an improvement in self-reported pain at the end of treatment as evidenced by a lower score on the Dysmenorrhea verbal rating scale (scale 0 to 3) compared with placebo. Additionally, they found a reduction in menstrual pain from baseline to the end of treatment. While these studies revealed mild improvement in a verbal and numerical decrease in endometriosis pain, the evidence was flawed in that there is considerable bias in what was being measured. Additionally, the reports varied widely (large confidence intervals). 

Combined oral contraceptive pill versus medical therapies

One underpowered trial compared the COCP with another medical treatment (goserelin), a Gonadotropin-releasing hormone receptor agonist. Even for this study, randomization, blinding, and allocation concealment was incomplete and thus had a considerable bias.

At the end of treatment, the women in the goserelin group were amenorrhoeic and therefore no comparisons could be made between the groups for the primary outcome. At six months' follow-up, there was no clear evidence of a difference between women treated with the COCP and women treated with goserelin for measures of dysmenorrhoea on a visual analogue scale (scale 1 to 10) or a verbal rating scale (scale 0 to 3)  At six months' follow-up, there was no clear evidence of a difference between the COCP and goserelin groups for reporting complete absence of pain as measured by the visual analogue scale or the verbal rating scale 

Based on the limited evidence from these trials at high risk of bias and limited data for the outcomes reported, there is insufficient evidence to make a judgment on the effectiveness of the COCP compared with placebo and the findings cannot be generalized. Further research is needed to fully evaluate the role of OCPs in managing pain-related symptoms associated with endometriosis. 

Research Source: https://www.ncbi.nlm.nih.gov/pubmed/29786828