Spotlight on… endometriosis

Endometriosis is one of the most common conditions we are likely to encounter in an outpatient gynaecology clinic setting, and The Obstetrician & Gynaecologist (TOG) has featured several articles on it. Endometriosis is associated with lower quality of life so it is reassuring to see that the UK government launched their 2024 priorities for the Women's Health Strategy at the Royal College of Obstetricians and Gynaecologists earlier this year with a focus on improving care and treatment for women with endometriosis. Symptomatic endometriosis is a chronic and debilitating condition that can affect women's quality of life. Typical symptoms include dysmenorrhoea, chronic pelvic pain, deep dyspareunia and painful defecation. Despite increasing awareness of endometriosis-related symptoms, there are often significant delays in reaching a definitive diagnosis; the average interval period in the UK is estimated to be 8 years.1 Significant symptoms overlap with other conditions is one of the reasons for this delay. Issa et al. (TOG 2016;18:9–16) write about the overlap of symptoms between endometriosis and irritable bowel syndrome and provide useful insights and guidance on appropriate investigations and management options. Treatment options for symptomatic endometriosis range from medical treatments to surgery but only few of them are found to be entirely satisfactory. Moore et al. (TOG 2000;2:25–8) discuss medical treatment options of endometriosis, which remain largely unchanged over the last couple of decades, while Hoo et al. (TOG 2017;19:131–8) expand on surgical options as well as complementary treatments. As our understanding of endometriosis has evolved, we have progressively moved away from performing hysterectomy and bilateral oophorectomy to minimally invasive excision surgery. However, the surgical techniques employed by surgeons vary widely. Fleischer et al. (TOG 2021;23:310–7) discuss the fundamentals of endometriosis surgery in a Tips and Techniques paper, introducing the SOSURE mnemonic to help maximise access and optimise assistance during endometriosis surgery. It is recognised that endometriosis exists in three distinct entities:2 peritoneal, ovarian and deep endometriosis, which are thought to represent manifestations of different disease processes. Kenney et al. (TOG 2007;9:147–52) appraise the evidence for different surgical approaches available based on the disease location and discuss their benefits and risks. Endometriosis is found to have higher prevalence among women with subfertility, and four main mechanisms are possibly implicated:3 distorted adnexal anatomy inhibiting oocyte capture after ovulation; impaired fertilisation; interference with early embryo development and reduced endometrial receptivity. Prasannan-Nair et al. (TOG 2011;13:1–6) talk about these mechanisms and propose management options depending on the severity of endometriosis. The more recent paper by Morris et al. (TOG 2024;26:32–43) revisits this topic and in addition presents the different scoring systems that have been developed to describe endometriosis at laparoscopy, including the revised American Society of Reproductive Medicine scoring system (rASRM), the ENZIAN scoring system and the endometriosis fertility index (EFI). It also discusses the role of assisted conception for women with endometriosis and subfertility, either to help them achieve parenthood or for fertility preservation, especially prior to surgery for excision of endometriomas. However, surgery might be needed before initiating assisted conception treatments to help optimise outcomes, as highlighted by Suresh et al. (TOG 2013;15:91–8). In this paper, indications for surgical management of endometriomas prior to IVF are discussed as well as the options of excision versus ablation of endometriomas. The presence of endometriosis is associated not only with subfertility but also with increased risk of obstetric and neonatal complications, and Rafi et al. (TOG;2022;24:242–50) discuss possible pathophysiology mechanisms implicated. This paper also provides guidance about preconception counselling and antenatal care especially for women with ‘high-risk endometriosis’, including women with adenomyosis, with surgically treated peritoneal and deep endometriosis or who conceived after assisted conception treatments.