What is Endometriosis

Endometriosis is defined as the presence of endometrial-like tissue outside the uterus, which induces a chronic, inflammatory reaction (Kennedy 2005). It can have a significant impact on the quality of a woman’s life including social and sexual relationships, work, and study (Nnoaham 2011, Simoens 2012, De Graaff 2013).

Endometriosis is thought to be an oestrogen-dependent disorder as amelioration of pre-existing endometriosis is seen after the menopause and endometrial tissue grows in animals on oestrogen therapy. The aetiology of endometriosis is unknown and controversial. Four main pathophysiological hypotheses have been put forward: retrograde menstruation, coelomic metaplasia, transformation of peritoneal mesenchymatous cells under the effect of endogenous biological factors contained in the substance of retrograde menstruation, and vascular/lymphatic embolization.

Endometriosis affects approximately 10% of women of reproductive age with a peak incidence found between ages 30 and 45 (Ozkan 2008). It is more prevalent in women with subfertility of whom 25% to 40% are affected (Dunselman 2014). The prevalence of endometriosis is even higher among symptomatic adolescents with ranges of 49% for those with chronic pelvic pain to 75% for those with pain unresponsive to medical treatment (Shafrir 2018). However, these values are likely to be underestimates of the true prevalence as direct visualisation of the disease via laparoscopy is required for a diagnosis. Visual recognition alone during laparoscopy is of limited value as it has a high false-positive rate. The lesions should be biopsied therefore to give a tissue diagnosis. Histology is definitive.

The diagnosis may be suspected on ultrasound especially if there is one or more endometriotic cysts known as endometriomas. An endometrioma has a classic appearance on ultrasound caused by the material within the cyst which is ‘chocolate-like’ when opened hence the term ‘chocolate cyst’. However, haemorrhagic cysts have a similar appearance and so surgery is still needed in most cases for a definitive diagnosis.

Time to Diagnosis

The diagnosis can be difficult to establish therefore plus the symptoms vary so much and can mimic several other conditions. Current data suggest it takes around eight years to establish the diagnosis in the UK and that women see, on average, seven physicians before being diagnosed (Ballard 2006, Nnoaham 2011, Dunselman 2014). This relates to delays in referring the woman from primary care to Gynaecology but also delays in secondary care in arranging definitive investigation by way of laparoscopy (Agarwal 2019). Other causes for the delay in diagnosis include intermittent use of contraceptives causing hormonal suppression of symptoms, the use of non-discriminatory examinations, misdiagnosis, attitude towards menstruation and normalisation of pain by the women, their mothers, family doctors, gynaecologists or other specialists (Ballard 2006, Hudelist 2012, Nnoaham 2011).

Most adults with endometriosis report that their pelvic pain began during adolescence (Nnoaham 2011). Unfortunately, most of these young women do not receive timely treatment. It follows that before a definitive diagnosis is made, women often endure symptoms for many years during which they suffer negative effects on their well-being and quality of life (Zondervan 2020). The long interval between symptom onset and diagnosis results in prolonged pain, decreased quality of life, psychological stress, and impaired fecundity (Nnoaham 2011, Agarwal 2019).

The Role of Laparoscopy

Laparoscopy is invasive and associated with both surgical and anaesthetic risks. In women with symptoms and signs suggestive of endometriosis, there is an argument for starting medical treatment (see below) before undertaking a laparoscopy. Empirical treatment, without a definitive diagnosis, under such circumstances is reasonable (Dunselman 2014).

Arguments to perform a laparoscopy include the woman’s wish to have a definitive diagnosis, infertility and/or symptoms and signs of advanced disease such as ovarian endometrioma and deep infiltrating disease. If signs of deep endometriosis or ovarian endometriosis are not present on physical examination and/or imaging, it can be argued that a diagnostic laparoscopy should not be performed especially in adolescents and young adults as it has not been shown that treatment of peritoneal disease influences the natural course of the disease (Dunselman 2014). Furthermore, it might not be successful in treating the pain symptoms. Treatment must be individualised therefore, taking the clinical problem in its entirety into account, including the impact of the disease and the effect of its treatment on quality of life, and the desire to conceive.

While the cause remains elusive, it is defined by the presence of tissue similar to the lining of the womb (the endometrium) growing in places outside of the womb such as the ovaries and the tissue that overlies the pelvic organs known as the peritoneum. Endometriotic deposits can be seen in the peritoneal tissue that lies underneath the ovaries on the pelvic side walls (the ovarian fossae) and over the rectum and bladder. The lesions can be ‘new’ and superficial or ‘old’ and deeply infiltrating with the formation of nodules. As endometriosis is an inflammatory condition, it can also result in the formation of adhesions which can affect any of the pelvic organs and the large bowel, namely the rectum and sigmoid colon. The extent and severity of the disease varies therefore from minimal-mild where there are a few, small lesions to moderate-severe where large, ovarian endometriotic cysts (endometriomas) are seen in association with extensive fibrosis in the uterosacral ligaments and adhesion formation causing anatomical distortion and obliteration of the pouch of Douglas (the area between the upper vagina and rectum). More rarely, the deposits can infiltrate into or through the bowel wall. Severity can be quantified and scored by the revised American Society of Reproductive Medicine (rASRM) staging classification.

Deep endometriosis is endometriosis that has penetrated deeper than 5 mm under the peritoneum (the layer of tissue lining the pelvic cavity). It is thought to affect 20% of women with pelvic endometriosis (Bazot 2017). This is much harder to see and is not adequately considered in the rASRM classification system. Surgical removal of deep endometriosis reduces endometriosis-associated pain and improves quality of life (De Cicco 2011). If there is clinical evidence of deeply infiltrating endometriosis (DIE), ureteric, bladder and bowel involvement must be assessed. Consideration should be given to performing MRI or ultrasound (transrectal and/or transvaginal and/or renal), with or without a CT Urogram and/or barium studies, to map the extent of disease if this has not been undertaken pre-operatively.

Clinicians should, therefore, perform clinical examination in all women suspected of endometriosis. Where vaginal examination may be inappropriate, for example for adolescents and/or women without previous sexual intercourse, rectal examination can be helpful. Deep endometriosis should be suspected in women with (painful) induration and/or nodules in the rectovaginal wall (Bazot 2009).

A negative diagnostic laparoscopy is highly accurate for excluding endometriosis providing it has been well performed and preceded by appropriate preoperative assessment (Dunselman 2014). It is significantly more accurate than MRI and is able identify deep infiltrating endometriosis (Khan 2018). Rectovaginal endometriosis does not have the classic discolouration of pigmented endometriosis. Rather, it typically has the appearance of superficial scar tissue in the pouch of Douglas that can be overlooked if not carefully assessed. In some cases, the pelvis and pouch of Douglas can appear completely normal even if there is a large endometriotic nodule which can be hidden under the bowel, which is retracted over it, and can only be detected when induration is felt by palpation (Koninckx 1994). It has been proposed that mild forms of deep infiltrating endometriosis may be missed at laparoscopy with one study reporting a sensitivity of primary laparoscopy of only 19% (Griffiths 2009). However, diagnosis during laparoscopy is dependent on the ability of the surgeon to recognize peritoneal disease in all its different appearances (Dunselman 2014). If the surgeon performing the laparoscopy is not familiar with these appearances, endometriosis may be missed and left untreated; the old adage that ‘you see only what you recognize’ very much applies. The laparoscopy must be performed systematically therefore and include a full and detailed inspection of the pelvis by a gynaecologist with training and skills in laparoscopic surgery for endometriosis (NICE 2017).

It has also been suggested that some missed diagnoses could be explained by disease progression since the primary laparoscopy. However, this is unlikely as it is unclear whether rectovaginal endometriosis is actually a progressive condition and even if progression does occur it is unlikely to be rapid (Griffiths 2009).

While imaging has a role, it is important to not exclude the possibility of endometriosis if the ultrasound scan or MRI are normal. The same applies to abdominal and pelvic examinations.

During a laparoscopy to diagnose endometriosis, laparoscopic treatment of peritoneal endometriosis not involving the bowel, bladder or ureter and/or uncomplicated ovarian endometriomas should be considered as this is associated with a reduction in pain and, where relevant, an improvement in fertility (NICE 2017). A ‘see and treat’ approach is recommended therefore, and this should be reflected in the consent process (Jacobson 2009, Dunselman 2014).

Clinical Features

There is no clear correlation between disease severity and the type or severity of pain symptoms, treatment response, or prognosis (Schliep 2015, Johnson 2017). Women with minimal-mild endometriosis may have severe pain. Furthermore, while some women with endometriosis experience painful symptoms and/or infertility, others have no symptoms at all including those with moderate-severe disease although many of these women describe experiencing pain in the past as outlined above.

The symptoms vary. Some women are badly affected, while others have no symptoms at all. The most common symptoms include abdomino-pelvic pain that is worse during menstruation, severe period pain (dysmenorrhoea), pain during or after sex (dyspareunia), and heavy periods (menorrhagia). Some women also experience pain when passing urine (dysuria) or when opening their bowels (dyschezia). Less frequently, women may also present with cyclical symptoms related to endometriosis at extra-pelvic sites such as the umbilicus or a caesarean section scar.

NICE recommend suspecting endometriosis in women, including young women aged 17 and under, who present with one or more of the following symptoms or signs (NICE 2017):

  • chronic pelvic pain
  • period-related pain (dysmenorrhoea) that affects daily activities and/or quality of life
  • deep pain during or after sexual intercourse
  • period-related or cyclical gastrointestinal symptoms specifically painful bowel movements
  • period-related or cyclical urinary symptoms specifically haematuria or dysuria
  • infertility in association with one or more of the above

Women with these symptoms should be offered an abdominal and pelvic examination to identify abdominal masses and pelvic signs, such as reduced organ mobility and enlargement, tender nodularity in the posterior vaginal fornix, and visible vaginal endometriotic lesions.

Natural History

Although endometriosis is a chronic inflammatory condition, its natural history is unknown. During each menstrual cycle, endometriotic lesions bleed resulting in repeated tissue injury and repair with local inflammation and the formation of new blood vessels and nerves (Chapron 2019). This in turn leads to fibrosis in the endometriotic lesions and surrounding tissue.

However, this is not synonymous with the progression of stage I or II disease into stage III or IV disease or superficial lesions into deeply infiltrating ones (Fedele 2004, Evers 2013). Indeed, in contrast to proliferative diseases such as cancer, endometriosis appears to be a relatively stable disease that progresses to fibrosis over time (Gonzalez-Foruria 2017). There is no evidence to show there is an ordered progression of endometriotic lesions, therefore. In studies where women have had repeat surgery, lesions progressed (29%), regressed (42%), or were unchanged (29%) (Evers 2013).

It follows that while endometriosis is generally considered a progressive disease, it can remain static and even regress without treatment (Sutton 1997). Surgery may even be a risk factor for the progression of endometriosis, as evidenced by the increased risk of endometriosis in patients with a history of surgery (Sibiude 2014). Understanding this is crucial when it comes to the management of patients with endometriosis.


Whilst there is no cure for endometriosis, there are several treatment options that can help alleviate symptoms, improve fertility, and possibly reduce the chance of the condition developing and becoming more severe and more extensive through fibrotic change.

When deciding the best treatment for endometriosis, it is crucial to consider the patient’s predominant symptoms and preferences, side-effect profile, and age, as well as the extent and location of disease, and, where relevant previous treatment (Zondervan 2020). The modern management of endometriosis should be patient-focused rather than focused on the endometriotic lesions and individualized according to the patient’s intentions and priorities (Chapron 2019).
Medical treatment should be the first therapeutic option for patients with pelvic pain who have no immediate desire for pregnancy. Medical treatment for endometriosis-associated pain focuses on suppression of systemic or local oestrogen suppression and/or inhibition of tissue proliferation and inflammation. It can be administered without histological confirmation or on a presumptive diagnosis.

As most women have pain, simple analgesia such as paracetamol and/or non-steroidal anti-inflammatories like ibuprofen and naproxen can help. However, these medications only treat the symptoms and have no impact on the underlying disease process which is hormonally driven by the cyclical waves of oestrogen. For this reason, hormonal treatment with the combined oral contraceptive pill or progesterone, given orally or parenterally including the Mirena coil, is often recommended.
One of the most effective hormonal treatments are Gonadotrophin-Releasing Hormone (GnRH) analogues. These must be given by injection every month and usually take a couple of months to take effect as they work by ‘down-regulating’ the cyclical production of oestrogen and progesterone by the ovaries. As a result, they are associated with bone demineralisation and menopausal symptoms, such as hot flushes and night sweats, but these can be countered by giving hormone replacement therapy (HRT) without any impact on the effectiveness of the injections. Providing the treatment is well tolerated and HRT add-back therapy in place, GnRH analogues can be used long-term without any concern over osteoporosis. GnRH analogues are typically used as a second-line treatment.

Surgery is also an effective treatment in many cases. The aim of surgery is to remove all of the endometriotic tissue including any nodules and cysts and to divide any adhesions (adhesiolysis) that are present and so return the pelvic anatomy to normal. However, this is not always possible especially with moderate to severe disease and one must strike a balance between undertaking extensive surgery and the risk of inadvertent bowel and other organ injury. The endometriotic lesions can be excised or destroyed by the application of electrodiathermy (cautery) or laser. The destruction of the lesions is referred to as ‘ablation’. The excision or ablation of endometriotic lesions has been shown to reduce pain and improve fertility but not in all women (Dunselman 2014). The evidence for the surgical treatment of superficial endometriosis for pain relief is sparse (Horne 2019).

The same applies to endometriotic cysts. These do not resolve but equally do not always need to be removed. The current recommendations are to remove endometriomas if they are causing pain or if they are ≥ 4 cm in diameter. The cyst can be excised (cystectomy) or opened and drained (cystotomy). Recurrence is higher with cystotomy and so cystectomy is recommended. However, cystectomy removes more normal ovarian tissue than cystotomy thereby reducing the number of follicles (and so eggs) within the ovary leading to a reduction in ‘ovarian reserve’. Recurrence after cystotomy can be reduced by treating all endometriotic tissue within the cyst as opposed to just draining it. Both options are reasonable therefore providing the patient is informed of their relative risks and benefits. Where surgery is planned, there is insufficient evidence to justify the use of pre- or post-operative hormonal treatment.

Surgical removal of deep endometriosis is recommended as it reduces endometriosis-associated pain and improves quality of life (Dunselman 2014). Such surgery is highly specialized as there is a higher rate of complications particularly when bowel surgery is required with a reported total intraoperative complication rate of 2% and total post-operative complication rate of 14% (Kondo 2011). Such surgery should be performed by specialists and ideally in an Endometriosis Centre (Dunselman 2014). Certainly, the management of endometriosis involving the bowel, bladder, ureters, or extrapelvic structures requires multidisciplinary expertise (Johnson 2017).

Medical therapy with progestogens or GnRH analogues may also be effective for recto-vaginal endometriosis and help reduce painful periods and non-menstrual pelvic pain as well as deep pain during intercourse (dyspareunia). However, deep infiltrating endometriosis is often resistant to medical treatment and usually requires surgical excision for cure.

The Role of Hysterectomy

Hysterectomy with bilateral salpingo-oophorectomy generally is reserved for women with debilitating symptoms attributed to endometriosis who have completed childbearing and in whom other therapies have failed (ASRM 2014). Unfortunately, hysterectomy is required in many cases. Indeed, endometriosis-associated pain is the leading indication for hysterectomy among women aged 30 to 34.

All visible endometriotic lesions should be excised at the time of the hysterectomy (NICE 2017). The cervix should be removed as endometriosis is often found in that area and so a total as opposed to a sub-total hysterectomy should be performed. As endometriosis is a hormonally driven condition, it can still recur and be as severe unless the ovaries are also removed (bilateral oophorectomy). Hysterectomy without oophorectomy is less effective, as disease recurrence and subsequent reoperation rates are higher (Namnoum 1995, Martin 2006). However, this induces an immediate menopause and so one has to be mindful of this and the patient’s age. If oophorectomy is intended, it is essential that the woman has been shown to be able to tolerate HRT and has no significant risk factors that would contraindicate such treatment. For this reason, no responsible Gynaecologist would proceed with oophorectomy unless these issues have been considered. The best way to assess the likely impact of oophorectomy on symptoms and tolerance of HRT is to do a pre-operative trial with GnRH analogues and HRT add-back therapy as outlined above. If the pain settles or is adequately ameliorated, it is reasonable to expect the same after oophorectomy. Combined HRT should be used with both oestrogen and progesterone. Oestrogen-alone is associated with a risk of recurrent endometriosis.

However, hysterectomy does not guarantee relief. Post-hysterectomy pain is three times as likely among women with pre-operative pain compared to those without pre-operative pain (Brandsborg 2018).


There is a relationship between endometriosis and subfertility (de Ziegler 2010). Mechanisms include chronic inflammation of the peritoneal fluid that leads to alteration of the fertilization process, disruption of ovarian function, abnormalities of the eutopic endometrium, pelvic adhesions, decreased frequency of sexual intercourse owing to pain during sex, and possible surgical damage to the ovary after the excision of endometriomas (Raffi 2012).

Women of reproductive age with endometriosis should be encouraged to pursue pregnancy at the earliest time that life circumstances allow therefore because their disease has the potential to threaten their fertility (ASRM 2014).

There are no medical treatments that are recommended to improve natural fertility in women with endometriosis. Suppression of ovarian function to improve fertility in minimal-mild endometriosis is not effective and should not be offered for this indication alone (Hughes 2010). There is also no evidence of its effectiveness in more severe disease.

Ablation of endometriotic lesions plus adhesiolysis improves fertility in minimal-mild endometriosis (Jacobson 2010). However, the role of surgery for moderate-severe disease is uncertain. Nevertheless, infertile women with stage III/IV endometriosis should be offered operative laparoscopy, instead of expectant management, to increase spontaneous pregnancy rates (Vercellini 2006).

Although surgical treatment of endometriosis in women without other identifiable infertility factors may improve rates of spontaneous pregnancy, it is unclear whether surgery improves the likelihood of pregnancy in women undergoing assisted reproductive technology such as in vitro fertilization (Dunselman 2014, ASRM 2012).

IVF is an effective treatment for more severe disease, especially if tubal function is compromised, and/or when other treatments have failed. Treatment with a GnRH agonist for 3-6 months before IVF in women with endometriosis may increase the rate of clinical pregnancy and should be considered (Sallam 2010). However, this must be balanced against the delay in treatment and the woman’s age. The effectiveness of surgical excision of deep nodular lesions before IVF on the outcome of treatment is unclear but may be beneficial (Bianchi 2009).

Women with endometriosis can be reassured that cumulative endometriosis recurrence rates are not increased after controlled ovarian stimulation for IVF/ICSI (D’Hooghe 2006, Benaglia 2010, Benaglia 2011).

However, a common issue with patients undergoing IVF is how to advise those with an asymptomatic endometrioma. Most Reproductive Medicine experts advise leaving the cyst under such circumstances as there is no impact on the chance of IVF working (Benschop 2010). However, if the endometrioma is aspirated by the egg collection needle, accidently or intentionally if this is the only way to access follicles, there is an increased risk of infection. That risk persists even if antibiotics are given and can be more severe than other pelvic infections and lead to formation of a tubo-ovarian abscess. Again, there is no definitive answer, but the patient should be informed of the risks and benefits of pre-treatment surgical intervention against those of IVF with the cyst still present.

As can be seen from the above, endometriosis can be a difficult condition to live with and deal with, both physically and emotionally. Despite the substantial effect that endometriosis has on women, their families, public and professional awareness of the disorder remains poor (Zondervan 2020). Patients are advised to speak to their GP and seek referral to a Gynaecologist with a special interest in the condition. There are many on-line resources and support groups including Endometriosis UK.

A Medicolegal Perspective

It can be difficult to establish liability therefore when considering the management of a woman who comes forward with a potential claim for a delayed diagnosis. Nevertheless, there is lots of evidence to show the diagnosis is often delayed and so a key question is whether this is ever reasonable?

As with most conditions, one needs an open mind and low threshold to consider the diagnosis of endometriosis. However, as the diagnosis invariably requires laparoscopy, healthcare practitioners also need to be mindful of the risks associated with this.

I find NICE’s recommendation to consider the condition in any woman of reproductive age with one or more of the symptoms most often associated with endometriosis to be very helpful in such matters. Their recommendation to extend this to adolescents is also very welcome and extremely important as so many young women are seemingly dismissed and told that it is normal to have painful periods. It follows that any woman of reproductive age with one or more of these symptoms is seen and examined.

Dependant on the symptoms and examination findings, consideration must be given to undertaking further imaging and/or referring the woman to gynaecology. Such referrals should ‘flag’ endometriosis as a possible differential. Clearly this responsibility falls to experts in primary care. Nevertheless, many women seen in secondary care are still not adequately assessed for the condition. It is not uncommon for a woman to be referred and then seen by a trainee who fails to undertake an internal examination. Whilst this may be normal, it can also reveal signs of endometriosis including a pelvic mass, a tender, fixed uterus, or induration and nodules in the posterior fornix. These are all consistent with severe and/or deeply infiltrating endometriosis and warrant further investigation prior to laparoscopy.

It is equally important to remember that a negative examination or a normal ultrasound scan do not exclude endometriosis. One must re-visit the symptoms and consider the role of laparoscopy. This is a joint decision with the patient who needs to be informed of the risks and benefits of surgery and the role of empirical medical therapy.

The woman’s desire to have children, at the time or in the future, must also be taken into consideration as this will impact the treatment offered. Medical treatment may help with pain but will not improve fecundity. In contrast, surgery will lead to a higher chance of natural conception in women with minimal to mild disease and allow quicker referral for IVF in those with more severe disease or tubal pathology.

When a laparoscopy is undertaken, it is paramount that this is performed by someone competent with a knowledge of endometriosis including its various manifestations and forms. As outlined above, isolated deeply infiltrating endometriosis in the rectovaginal septum can be missed unless the area is meticulously examined. I have seen many trainees undertake what they feel to be a full laparoscopic assessment despite failing to fully expose and explore the ovarian fossae and the rectovaginal septum. The procedure actually requires a fairly basic level of competence, but without due care and attention, I can see how endometriosis can be missed.

This begs the question whether endometriosis has been missed or developed in those women who have a second laparoscopy following an initially negative laparoscopy. This is a difficult question to answer given the uncertain nature of endometriosis and will largely be determined by the severity of the disease, its location, and the interval between the two procedures. An expert needs to be mindful of making assumptions about disease progression given the enigmatic nature of the condition. However, I also find the answer can be informed by the patient’s symptoms at the time of each procedure. If these are unchanged and there is no other identifiable cause, then that would support an initial failure to make the diagnosis at the index procedure.


This is often less controversial. As outlined above, medical and surgical management are both reasonable options unless the patient is intending to conceive. Both are as effective as each other in the treatment of pain providing the woman does not have an endometrioma or deeply infiltrating disease when surgery is preferred. A key part of the decision is to exclude these disease entities, therefore. That requires a meticulous examination and a transvaginal pelvic ultrasound scan at the very least plus further imaging if there is a suspicion of deep disease such as MRI, rectal ultrasound, and so on. Such diagnoses can be missed if treatment is undertaken without such assessments. I have seen many women be diagnosed with deeply infiltrating disease at the time of laparoscopy which should have been readily evident had a vaginal examination been undertaken. One may argue the diagnosis has still been made, but had it been suspected before surgery, further investigations could have been carried out and the woman referred to an Endometriosis Centre. This may have allowed the treatment of the deep disease at the index laparoscopy as this is more complex surgery that requires a different level of competence and experience. The same applies to an endometrioma. One cannot remove an endometrioma without prior consent and an understanding of the patient’s view on cystectomy versus cystotomy.

Empirical medical treatment is reasonable and can be achieved with a variety of medications using a classic systematic approach focused on the patient’s symptoms and risk factors for both hormonal and non-hormonal therapy. GnRH analogues are usually used as a secondary option but can also be started as a first line treatment for women with severe pain. It is important to review the woman a few months after initiating treatment to assess its impact. The role of surgery can be explored at the same time.

Many women chose to have a laparoscopy as this confirms the diagnosis. As laparoscopic excision of endometriosis and the division of adhesions improves pain, women should be consented for an operative laparoscopy as opposed to a diagnostic one. Failure to do so means treatment cannot be undertaken. The woman is then faced with the decision of having a second laparoscopy or using medication which takes time to work and has certain risks and side effects.
Equally, women should be advised to have a Mirena coil or use a contraceptive pill after the surgical treatment of endometriosis as this reduces the risk of recurrent pain. I find this something this is frequently missed despite being advised by ESHRE.

Other issues that I have been asked to consider as an expert include the standard of surgery undertaken both when performing conservative laparoscopic surgery and/or hysterectomy. Endometriosis can be extremely difficult to operate on. It makes tissues planes harder to define and, in many cases, involves dense adhesions between the bowel and the pelvic organs. In addition, the ureters can be involved or lie under an area of peritoneal endometriosis that needs excision or ablation. As a result, there is a much higher risk of inadvertent injury to the bowel, bladder, and ureters as well as the other pelvic organs. The risk of bleeding and infection is also increased. The patient must be made aware of these risks and, where relevant, measures put in place to reduce the risk. This can involve a joint approach with another surgeon, prophylactic ureteral catherization, bowel preparation, and so on. When undertaking hysterectomy, the role of oophorectomy and removal of the cervix must be discussed along with the need for HRT. I have been involved in many cases where there has been no discission about the beneficial role of oophorectomy or a subtotal hysterectomy has been performed in a woman with known rectovaginal disease. Suffice to say these have all been settled in favour of the Claimant.


We have established that whilst endometriosis is a chronic condition, it is not necessarily a progressive one. Indeed, it is just as likely to not change or to regress. It follows that a Claimant will struggle to show her endometriosis became worse as a result of a delayed diagnosis. However, there is evidence that when left untreated, active endometriotic lesions become increasingly fibrotic. This can be seen and quantified laparoscopically. Such changes may result in more severe pain, but we also know many women with severe endometriosis and extensive adhesions are asymptomatic or have minimal pain. Nevertheless, fibrosis, scarring and adhesions all increase the complexity of surgery regardless of the indication.

Many women with asymptomatic endometriosis who have scarring and fibrosis indicative of old disease, describe pain when younger. This is because, on the balance of probabilities, they had active endometriosis at that time.

One of the strongest cases a Claimant can put forward therefore is the pain and suffering she has suffered as a result of a delayed diagnosis. Indeed, my own Trust, Nottingham University Hospitals, was recently involved in a case where a woman was awarded £500,000 compensation as an out-of-court settlement for a 15-year delay in diagnosing her endometriosis (BMJ 2020). The Claimant had first attended a Gynaecology appointment with symptoms of endometriosis in 1997 when aged 14. The pain continued and the Trust admitted a laparoscopy should have been performed in 2001, when the Claimant reached 18. She described symptoms consistent with endometriosis and asked the medical team whether she had the condition. Her suggestion was seemingly dismissed. When a laparoscopy was finally carried out in 2015, the Claimant was found to have stage IV endometriosis with extensive adhesions. She was also infertile and went through in vitro fertilisation which was successful, and she had a son in 2018. A key part of this claim was the role of social media and support groups which the Claimant used to inform her own diagnosis which was then rejected by the healthcare practitioners looking after her.

The case resonates with the studies I have referred to that show many young women are unreasonably dismissed. This must stop. I sincerely hope Endometriosis Awareness Month goes some way to achieving this. I have repeatedly said that the only way I see patients suffering less is if they themselves are informed and bring evidence-based questions to their healthcare practitioners who they should challenge if they feel dismissed. The same applies to women who suffer ovarian torsion and ectopic pregnancy. Very different conditions to endometriosis but also ones with life changing implications if not diagnosed and managed in the timely manner.

About the Author

Mr. Raine-Fenning is a Consultant Gynaecologist working at Queen’s Medical Centre and Reader/Associate Professor of Reproductive Medicine and Surgery.

Nick is an internationally recognised expert in three-dimensional ultrasound and gynaecological imaging and has given over 100 invited talks, plenary sessions and workshops.

He was awarded a PhD in 2004 for work relating to the quantification of pelvic blood flow.

He has over 13 years of experience in medico-legal work.

He has provided over 1000 reports on Liability and Causation and Condition and Prognosis and is formally trained in report writing and giving evidence in court.

Mr Raine-Fenning can be contacted for all medico-legal work and to request his CV at nicholasrainefenning@inneg.co.uk

Speak to Mr Raine-Fenning