CHC for pelvic pain in women with endometriosis: ineffectiveness or discontinuation due to side-effects

Paul J Yong; Najla Alsowayan; Noga H; Christina Williams; Catherine Allaire; Lisonkova S; Mohamed A Bedaiwy

doi:10.1093/hropen/hoz040

General Gynecology · Pelvic Pain

CHC for pelvic pain in women with endometriosis: ineffectiveness or discontinuation due to side-effects

Yong PJ, Alsowayan N, Noga H, Williams C, Allaire C, Lisonkova S, Bedaiwy MA

Published February 28, 2020 Human reproduction open

DOI 10.1093/hropen/hoz040 PMID 32128454 PMC PMC7048681

Read our synopsis

RRM Academy Synopsis

Worse pelvic pain tied to continuous pill failure in endometriosis

In 373 women with endometriosis at one Canadian center, worse chronic pelvic pain was linked to continuous pills failing. The pills are a suppressive medication. About 3 out of 10 women said cyclical use had not helped their pain. Poorer quality of life was linked to stopping continuous use over side-effects.

Key Findings

Prior cyclical use was reported by 228 (61.1%) of the 373 women. Prior continuous use was reported by 175 (46.9%).
Cyclical use: 103 (27.6% of all 373) said it was ineffective for their pain. Another 94 (25.2%) stopped it because of side-effects.
Continuous use: 67 (18.0% of all 373) said it was ineffective. Another 59 (15.8%) stopped it because of side-effects.
Worse chronic pelvic pain over the past 3 months went with continuous ineffectiveness (P < 0.001). Poorer quality of life went with continuous discontinuation due to side-effects (P = 0.005).
Pelvic floor tenderness was associated with cyclic ineffectiveness (P = 0.003) and continuous ineffectiveness (P < 0.001).

Interpretation

The study is a cross-sectional analysis of a prospective patient database. Women recalled past pill use at one visit, so the results show associations. The authors state that cause and effect cannot be established. Ineffectiveness was self-reported without standardized criteria, and the type of side-effect was not recorded. All 373 women came from one tertiary referral center. The authors suggest that muscle or nerve contributors to pain, which hormonal suppression does not directly treat, may explain the failures. They call for prospective data.

RRM Context

The authors say combined hormonal contraception works by suppressing estrogen made by the ovaries. Restorative reproductive medicine looks for the cause of pelvic pain before choosing treatment, and excision is the surgical standard for endometriosis. In this group, a tender pelvic floor was associated with pill ineffectiveness. That fits an evaluation that checks muscle and nerve contributors as well as lesions.

Our editorial summary of this paper, not the article's abstract.

Abstract

Study Question

What are the use patterns and factors associated with combined hormonal contraception (CHC) ineffectiveness or discontinuation due to side-effects in patients with endometriosis and pelvic pain?

Summary Answer

Worse chronic pelvic pain (CPP) severity and pelvic floor myalgia were associated with continuous CHC ineffectiveness, while poorer quality-of-life was associated with continuous CHC discontinuation due to side-effects.

What Is Known Already

CHC is a first line of therapy for endometriosis-associated pelvic pain in women. However, some patients state that CHC is ineffective for their pain, while others have to discontinue CHC due to side-effects.

Study Design, Size, Duration

Analysis of a prospective patient database from a tertiary care referral center for patients with endometriosis and pelvic pain between December 2013 and April 2015 was carried out.

Participants/Materials, Setting, Methods

A total of 373 patients of reproductive age with endometriosis from the database were included in the study. Data included patient self-reported questionnaires, physical examination findings and validated instruments. There were four variables of interest: history of cyclical CHC ineffectiveness (yes/no), history of cyclical CHC discontinuation due to side-effects (yes/no), history of continuous CHC ineffectiveness (yes/no) and history of continuous CHC discontinuation due to side-effects (yes/no). The primary outcome was CPP severity for the past 3 months (score of 0-10), and secondary outcomes were other pelvic pain scores, quality-of-life on the Endometriosis Health Profile 30 (EHP-30) and underlying conditions including irritable bowel syndrome, painful bladder syndrome, abdominal wall pain, pelvic floor myalgia and depression, anxiety and pain catastrophizing.

Main Results and the Role of Chance

Among the 373 cases in the dataset, prior cyclical CHC use was reported by 228 (61.1%) women, of which 103 (27.6%) stated it was ineffective for their pain and 94 (25.2%) stated they discontinued CHC due to side-effects. Previous continuous CHC use was reported by 175 (46.9%) women, of which 67 (18.0%) stated it was ineffective and 59 (15.8%) stated they discontinued due to side-effects. Worse CPP severity in the last 3 months was associated with a history of continuous CHC ineffectiveness (P < 0.001). Poorer quality-of-life was present in women who reported a history of continuous CHC discontinuation due to side-effects (P = 0.005). Among the underlying conditions, pelvic floor tenderness (as a marker of pelvic floor myalgia) was associated with CHC ineffectiveness.

Limitations, Reasons for Caution

This study involved patient recall and no longitudinal follow-up. Also, we do not have data on the type of side-effect that led to discontinuation. Medication ineffectiveness was reported subjectively by the patient rather than using standardized criteria. Finally, the diagnosis of endometriosis was based on previous surgery or a current nodule or endometrioma on examination/ultrasound; without prospective surgical data on all the patients, it was not possible to do a sub-analysis by current surgical features (e.g. stage).

Wider Implications of the Findings

In women with endometriosis, CHC ineffectiveness was associated with worse CPP and pelvic floor myalgia, which suggests myofascial or nervous system contributors to CPP that does not respond to hormonal suppression. A tender pelvic floor, as a sign of pelvic floor myalgia, may be a clinical marker of patients with endometriosis who are less likely to have an optimal response to hormonal suppression. For women who discontinue CHC due to side-effects, research is needed to help alleviate these side-effects as these patients report worse quality-of-life.

Study Funding/Competing Interests

This work was supported by a Canadian Institutes of Health Research (CIHR) Transitional Open Operating Grant (MOP-142273) as well as BC Women's Hospital and the Women's Health Research Institute. PY is also supported by a Health Professional Investigator Award from the Michael Smith Foundation for Health Research. MB/CA has financial affiliations with Abbvie and Allergan; the other authors have no conflicts of interest.

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General Gynecology › Pelvic Pain › Chronic Pelvic Pain · Therapeutics › Hormonal Agents › Estrogen Preparations · Endometriosis › Medical Management › Hormonal Suppression Outcomes

Paul J Yong, Najla Alsowayan, Christina Williams, Catherine Allaire, Mohamed A Bedaiwy

P Yong, N Alsowayan, C Williams, Cathy Allaire, Kate Allaire, C Allaire, M Bedaiwy

PMID 32128454 32128454 DOI 10.1093/hropen/hoz040 10.1093/hropen/hoz040 Yong et al. 2020, Yong 2020