Surgery as a fertility-enhancing treatment in women with endometriosis
Dr. Adrien Crestani, Surgeon in Complex Endometriosis Care, Instructor IFEM Endo.
Endometriosis affects approximately 10% of women of reproductive age, and infertility is reported in 30–50% of affected patients.
Although assisted reproductive technology (ART) has become central to their management, surgery remains a genuine fertility-enhancing treatment. By restoring pelvic anatomy, releasing tubo-ovarian adhesions and treating inflammatory lesions, surgery can improve spontaneous fertility and may also optimise the results of subsequent ART.
The relevant question is therefore not whether surgery should replace IVF, but which sequence offers each patient the highest cumulative probability of achieving a live birth. This assessment must include spontaneous pregnancies, which are sometimes undervalued in studies focusing exclusively on ART outcomes.
For many patients, preserving the possibility of conceiving naturally is an important therapeutic objective. Some wish to avoid repeated ovarian stimulation, oocyte retrieval and embryo transfer, while others want to reduce the physical and psychological burden of IVF.
When compatible with age, ovarian reserve, tubal patency and semen parameters, favouring spontaneous conception is a legitimate medical strategy.
Superficial endometriosis: evidence for improved spontaneous fertility
The strongest randomised evidence supporting fertility-enhancing surgery concerns minimal or mild endometriosis.
In the Canadian Collaborative Group trial, laparoscopic excision or ablation increased the cumulative ongoing pregnancy rate compared with diagnostic laparoscopy alone: 30.7% versus 17.7% [1].
A Cochrane meta-analysis subsequently confirmed that operative laparoscopy improves viable intrauterine pregnancy and live-birth outcomes compared with diagnostic laparoscopy alone [2].
The absolute benefit is moderate, but the direction of effect is consistent: treating superficial lesions and associated adhesions improves spontaneous fertility. Systematic diagnostic laparoscopy is not required in every asymptomatic woman with unexplained infertility.
However, when endometriosis is suspected and laparoscopy is otherwise justified by pain, imaging, examination or associated pelvic disease, visible lesions should be treated and normal tubo-ovarian anatomy restored whenever possible.
In young women with patent tubes, preserved ovarian reserve and normal semen parameters, surgery can therefore create a genuine postoperative window for spontaneous conception.
Endometriomas: treating the disease while preserving the ovary
Endometriomas may impair ovarian function through inflammation, oxidative stress, fibrosis and progressive follicular loss. They can also distort tubo-ovarian anatomy and, when large, complicate oocyte retrieval. Surgery may improve spontaneous fertility by treating the cyst, releasing the ovary and restoring its relationship with the fallopian tube.
Nevertheless, the technique is critical. Cystectomy may inadvertently remove healthy ovarian cortex and cause vascular or thermal injury. The postoperative decline in anti-Müllerian hormone is particularly concerning after bilateral or repeat surgery [3]. Fertility surgery should therefore aim not simply to remove the cyst, but to treat the endometrioma while preserving the largest possible volume of functional ovarian tissue.
Ablative techniques using plasma energy or CO₂ laser, as well as ethanol sclerotherapy, have been developed with this objective. A 2026 network meta-analysis including 21 randomised trials and 1,519 patients found more favourable short-term AMH or antral follicle count outcomes with several conservative techniques than with cystectomy alone [4].
However, most studies evaluated ovarian reserve markers rather than pregnancy or live birth.
The multicentre ATOPE trial (NCT07119060), developed at IFEM Endo Bordeaux, directly addresses this limitation. Women with 2–6 cm endometriomas are randomised between cystectomy and plasma-energy vaporisation, with 166 patients planned in each group. Women with endometriomas larger than 6 cm enter a prospective laparoscopic ethanol-sclerotherapy cohort. The primary endpoint is cumulative pregnancy at 24 months.
ATOPE will therefore determine whether better preservation of ovarian tissue translates into a meaningful reproductive benefit.
Although endometriomas may occur in isolation, they frequently coexist with adhesions, superficial lesions or deep endometriosis. Surgical planning should consequently be based on comprehensive disease mapping rather than cyst diameter alone.
Deep endometriosis: spontaneous pregnancy remains a meaningful outcome
Observational studies consistently report postoperative pregnancy rates of approximately 40–70% after surgery for deep endometriosis, with a substantial proportion occurring spontaneously. In a series of women undergoing surgery for colorectal endometriosis, Roman et al. reported high postoperative fertility, including spontaneous pregnancies among patients who had previously been infertile [5].
Surgery may restore pelvic anatomy, release the ovaries and tubes, treat associated superficial disease and reduce the inflammatory lesion burden.
It may also improve deep dyspareunia, allowing couples to resume regular intercourse. These different effects can create a real opportunity for spontaneous conception.
The absence of large randomised trials should not be interpreted as evidence that surgery is ineffective. Randomisation between complex surgery and IVF is difficult because patients often have strong preferences and because the two strategies do not offer identical outcomes.
IVF may achieve pregnancy without treating pain, dyspareunia, organ involvement or altered anatomy. Surgery addresses the disease itself and may be followed by either spontaneous conception or ART.
Ferrier et al. compared first-line surgery with first-line ART in women with deep endometriosis without colorectal involvement [6]. After propensity-score matching, 92 patients were included in each group. Pregnancy rates were 72% after first-line surgery and 35% after first-line ART, while live-birth rates were 61% and 24%, respectively. Seventeen women in the surgical group conceived without ART, and fewer IVF-ICSI cycles were required after surgery.
Residual confounding cannot be excluded because this was not a randomised trial. Nevertheless, the magnitude and consistency of the results support surgery as a valid first-line fertility strategy in selected patients with deep endometriosis. They also suggest that surgery and ART can be complementary: surgery may restore spontaneous fertility while improving the effectiveness of subsequent ART when natural conception does not occur.
Reconsidering surgery after IVF failure
Ballester et al. evaluated IVF-ICSI outcomes in 75 infertile women with unoperated colorectal endometriosis [7]. The cumulative pregnancy rate reached 68.6% after three cycles, confirming that IVF can be effective without prior colorectal surgery. However, little additional benefit was observed beyond the third cycle. Outcomes were poorer in women over 35 years, those with an AMH level below 2 ng/mL and, particularly, those with associated adenomyosis.
These findings support multidisciplinary reassessment after two unsuccessful IVF-ICSI cycles, before automatically proceeding to a third or subsequent attempt. Surgery should be actively reconsidered when spontaneous conception remains realistic, pelvic anatomy can be improved, symptoms are significant or untreated deep disease may be contributing to repeated failure.
This is not a rigid rule requiring surgery after exactly two failed cycles. Rather, it identifies a clinically relevant point at which repeating the same ART strategy may offer diminishing returns. Bendifallah et al. subsequently reported higher pregnancy and cumulative live-birth rates when surgery for colorectal endometriosis preceded IVF than with first-line ART, particularly over the first two IVF-ICSI cycles [8].
Surgical quality determines reproductive benefit
“Surgery” is not a standardised intervention. Outcomes depend on preoperative mapping, recognition of all disease sites, meticulous adhesiolysis, preservation of reproductive organs, haemostatic technique and access to colorectal or urological expertise.
When surgery is indicated, complete treatment of the lesions selected for excision should be sought. In one retrospective study, incomplete excision of deep endometriosis was associated with a substantially higher recurrence rate than complete excision: 35.3% versus 3.9% [9]. Leaving significant residual disease may maintain the anatomical and inflammatory mechanisms that prompted surgery and expose the patient to further treatment.
Completeness must not, however, be confused with indiscriminate radicality. Removing every visible lesion is not justified if it causes irreversible damage to healthy ovarian tissue, the fallopian tubes, uterus, pelvic nerves or other structures essential to reproduction. The objective is a complete planned procedure with maximal organ preservation. Deliberately conservative surgery is fundamentally different from an unplanned incomplete operation caused by inadequate mapping or insufficient expertise.
Centre experience also influences safety. A 2026 French nationwide study including 15,364 operations for posterior deep endometriosis found severe postoperative complications or readmissions in 5.3% of patients treated in centres performing fewer than 40 procedures annually, compared with 3.6% in higher-volume centres [10].
After adjustment, higher surgical volume remained associated with a lower risk of severe complications.
An inadequately planned initial operation may leave residual disease, create additional adhesions and make subsequent surgery more difficult. Repeat ovarian surgery may also produce cumulative follicular loss. Consequently, when complex surgery is required—particularly in patients with infertility or a desire for future pregnancy—it should be performed by an experienced multidisciplinary team in an expert centre.
The patient’s priorities extend beyond pregnancy rates
In many situations, pain and quality of life should remain primary clinical priorities rather than pursuing pregnancy as an isolated objective. Surgery can substantially reduce endometriosis-associated pain, particularly deep dyspareunia, while improving sexual function and quality of life [11].
By making intercourse possible or less painful, surgery may indirectly restore the possibility of spontaneous conception. These benefits are clinically meaningful even if pregnancy is subsequently achieved through ART.
A treatment strategy that results in pregnancy but leaves the patient with disabling pain cannot automatically be considered superior to one that treats the disease and preserves several routes to conception.
Choosing the right sequence
Surgery and ART should not be regarded as competing treatments. Surgery is most likely to enhance fertility in younger women with preserved ovarian reserve, patent tubes, normal semen parameters, pain or dyspareunia, altered pelvic anatomy and a desire for spontaneous conception. Direct IVF may be more appropriate when reproductive time is limited by age, diminished ovarian reserve, bilateral recurrent endometriomas, tubal occlusion or significant male-factor infertility.
Following surgery, the Endometriosis Fertility Index can help estimate the probability of spontaneous pregnancy and determine how long natural conception should be attempted before proceeding to ART [12].
The objective is not maximal anatomical excision at any cost. It is to achieve the highest cumulative probability of live birth while treating pain, preserving reproductive organs and minimising surgical morbidity and loss of reproductive time.
In appropriately selected patients, a complete fertility-preserving procedure performed in an expert centre should be regarded as a major component of the treatment of endometriosis-associated infertility.
Dr. Adrien Crestani, Surgeon in Complex Endometriosis Care, Instructor IFEM Endo.
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