Endometriosis, Egg Quality, and IVF: What Testing and Treatment Decisions May Involve

Summary: Endometriosis can affect fertility in several ways, including ovarian reserve, pelvic anatomy, and—in some patients—the response to controlled ovarian stimulation during IVF. However, a diagnosis of endometriosis does not imply that IVF will be unsuccessful. The most appropriate diagnostic and treatment pathway depends on maternal age, baseline ovarian reserve parameters (such as AMH and AFC), endometrioma presence and size, symptoms, prior ovarian surgery, tubal patency, and semen analysis.

How Can Endometriosis Affect Fertility?

Endometriosis is a chronic inflammatory condition affecting approximately 10% of women of reproductive age, with clinical literature indicating that a significant proportion of affected individuals experience subfertility or infertility (ESHRE Guidelines, 2022). The condition is characterized by the presence of endometrial-like stroma and glands outside the uterine cavity, most commonly involving the ovaries, broad ligaments, and the pouch of Douglas.

Pathophysiologically, the disease can influence reproductive function across multiple levels:

• Anatomical Factors: Pelvic adhesions may mechanically alter the position of the ovaries or compromise fallopian tube mobility and patency, affecting ovum pickup and transport.
• Peritoneal Environment: Elevated concentrations of pro-inflammatory cytokines (such as IL-1β, IL-6, and TNF-α) and reactive oxygen species in the peritoneal fluid may create an unfavorable environment for gamete interaction and fertilization.
• Endometrial Receptivity: Progesterone resistance and altered gene expression in the eutopic endometrium have been investigated as potential contributors to altered implantation dynamics in some individuals.

Clinical classification systems—such as the revised American Society for Reproductive Medicine (rASRM) staging (Stages I–IV) and the ENZIAN classification for deep endometriosis—describe the anatomical distribution and depth of lesions. While rASRM staging is assigned intraoperatively during surgery, expert transvaginal ultrasound plays an important role in non-invasive clinical evaluation by helping map ovarian endometriomas and deep endometriotic nodules. Correlation between rASRM numerical stage, pain severity, and spontaneous conception rates can be variable. To assist in evaluating prognosis for natural pregnancy following surgical evaluation, clinicians may utilize tools such as the Endometriosis Fertility Index (EFI), which integrates patient history with surgical findings.

How Does Endometriosis Relate to Oocyte Biology?

The development of a fertilizable competent oocyte depends on a complex microenvironment within the ovarian follicle. In patients with endometriosis, localized inflammatory mechanisms have been studied to understand their potential impact on follicular biology.

Intra-Follicular Environment and Oxidative Markers

Laboratory findings suggest that follicular fluid surrounding oocytes in individuals with endometriosis may exhibit higher concentrations of inflammatory markers and oxidative stress indicators compared to controls. Research into these microscopic findings evaluates several proposed mechanisms:

• Mitochondrial Function: Oxidative stress has been associated with altered mitochondrial activity within the cytoplasm, which plays a role in cellular energy dynamics during early cleavage stages.
• Meiotic Spindle Assembly: Localized inflammatory factors may affect spindle alignment during meiosis, which laboratory studies suggest could influence fertilization rates or embryo morphology in specific cohorts.
• Cumulus Cell Signaling: Paracrine interaction between cumulus cells and the developing oocyte may be altered by localized inflammatory mediators.

Ovarian Endometriomas and Surrounding Tissue

In the presence of ovarian endometriomas, intra-cystic fluid contains free iron, proteolytic enzymes, and inflammatory compounds. Passive diffusion of inflammatory mediators across the cyst wall may affect adjacent ovarian tissue, potentially contributing to localized micro-vascular changes or focal parenchymal alterations in surrounding cortical tissue.

Clinical Context: While laboratory investigations demonstrate microscopic and biochemical variations in follicular fluid, clinical data regarding cumulative Live Birth Rates (LBR) present a broader perspective. Maternal age remains a primary determinant of chromosomal status and overall embryo developmental potential. Consequently, oocytes retrieved from younger patients with endometriosis frequently retain significant developmental competence when fertilized within a controlled laboratory environment.

What Is the Impact of Endometriomas on Ovarian Reserve Markers?

Ovarian reserve refers to the pool of resting primordial follicles within the ovaries. Ovarian endometriomas may influence reserve parameters through physical presence, localized mechanical tissue strain, and associated biological factors prior to medical or surgical management.

Serum Anti-Müllerian Hormone (AMH) and Antral Follicle Count (AFC) serve as primary surrogate markers for quantitative ovarian reserve. Studies indicate that individuals with bilateral endometriomas often present with lower baseline median AMH values compared to those with unilateral disease or unaffected controls.

It is important to clarify that lower AMH or AFC values primarily predict a lower yield of retrieved oocytes during controlled ovarian stimulation, rather than serving as an absolute indicator of individual oocyte quality or the potential to achieve a pregnancy.

How Does Surgery for Endometrioma Affect Ovarian Reserve and IVF Yield?

The decision to perform surgical cystectomy prior to IVF involves careful weighing of potential benefits and risks. While surgery can relieve pelvic pain symptoms and improve physical access to follicles during oocyte retrieval, surgical excision of an endometrioma wall carries a risk of inadvertent removal of adjacent functional ovarian tissue or thermal damage to vascular supply.

Clinical Considerations in Surgical Management

• Ovarian Reserve Trends: Laparoscopic excision of endometriomas is associated with a post-operative reduction in serum AMH levels, with the degree of decline depending on cyst size, surgical technique, and whether the disease is unilateral or bilateral.
• Ovarian Stimulation Response: A history of prior endometrioma surgery is associated with an increased likelihood of reduced oocyte yield during subsequent IVF cycles.
• Surgical Preservation Principles: When surgery is clinically indicated—such as for severe, treatment-resistant pelvic pain, rapid cyst growth, suspicious imaging features, or compromised follicle accessibility—techniques designed to preserve ovarian stroma (e.g., precise excision or laser ablation rather than aggressive electrocautery) may be considered. ESHRE guidelines suggest that conservative non-surgical management is often preferred prior to IVF unless specific clinical indications are met.

How Does Endometriosis Influence IVF Management and Outcomes?

Endometriosis may be associated with a lower ovarian response in some patients, particularly in the presence of ovarian endometriomas or after prior ovarian surgery. However, its effect on fertilisation, embryo development, implantation, and live birth is not uniform across studies. Age, ovarian reserve, disease phenotype, tubal status, semen parameters, and prior treatment history often have a greater influence on an individual IVF plan.

Controlled Ovarian Stimulation (COS) Strategies

Stimulation protocols are individualized according to age, baseline AMH/AFC, and clinical history. Standard protocols, such as GnRH antagonist regimens, are widely utilized. In selected clinical scenarios, tailored protocols incorporating adjunctive agents (such as aromatase inhibitors) or specific down-regulation regimes may be evaluated on an individual basis by the treating specialist.

Procedural Safety Measures

During transvaginal ultrasound-guided oocyte retrieval, care is taken to avoid direct puncture of an endometrioma to minimize the risk of pelvic infection or abscess formation. Standard clinical practices include:

• Designing retrieval trajectories to collect follicles while avoiding entry into endometriotic cysts wherever technically feasible.
• Clinicians may consider antibiotic prophylaxis in selected patients with endometriomas; the decision and choice of agent follow local clinical protocols, allergy history, and clinical assessment.

Treatment Outcomes

While advanced-stage disease or progesterone resistance may influence implantation parameters in specific sub-groups, overall outcomes remain encouraging when age-adjusted, developmentally competent embryos are transferred. Individualized treatment planning and tailored luteal phase support are key components of cycle management.

How Are Individual Treatment Plans Determined?

Formulating an evidence-based fertility care plan requires an individualized assessment that integrates multiple diagnostic parameters:

• Maternal Age: Age remains a central factor influencing oocyte quality and chromosomal status, guiding decisions regarding protocol choice and embryo transfer strategies.
• Ovarian Reserve Profile: Baseline serum AMH, transvaginal AFC, and hormone profiles help set realistic expectations for follicular response and guide medication dosage.
• Anatomical and Partner Factors: Evaluation of tubal patency via hysterosalpingography (HSG) or hysterosalpingo-contrast-sonography (HyCoSy), combined with semen analysis, helps determine whether conservative approaches, intrauterine insemination (IUI), or direct progression to IVF is most appropriate.
• Prior Surgical History: A history of previous ovarian operations prompts careful consideration of non-surgical options to preserve remaining follicular reserve.

What Role Does Fertility Preservation Play?

For young individuals diagnosed with progressive endometriosis or those scheduled for pelvic surgery who do not wish to conceive immediately, fertility preservation through planned oocyte vitrification (egg freezing) may and should be discussed.

Oocyte Vitrification

Planned cryopreservation of mature oocytes may be evaluated individually, particularly in scenarios involving:

• Extensive or progressive endometriotic disease.
• Anticipated repeat ovarian surgery.
• Adequate residual ovarian reserve markers.

Vitrification preserves oocytes at the patient's current age, offering flexibility before age-related or disease-related changes in ovarian reserve progress. Decisions regarding fertility preservation are individualized following comprehensive counseling.

Clinical Evaluation and Care Pathways in Dubai

Managing subfertility associated with endometriosis requires a balanced, patient-centered approach combining diagnostic accuracy with evidence-based reproductive medicine.

For individuals seeking specialist evaluation in Dubai, initial consultations incorporate detailed clinical history, high-resolution transvaginal ultrasound mapping, quantitative ovarian reserve testing, and partner semen analysis. Treatment plans focus on ovarian tissue preservation, individualized stimulation protocols, and evidence-led clinical pathways tailored to each patient's specific health profile.

Frequently Asked Questions

Can IVF be performed in the presence of an endometrioma?

Yes, IVF can be carried out when an endometrioma is present. Current clinical evidence indicates that small to moderate endometriomas do not automatically preclude successful stimulation or embryo transfer. Care is taken during oocyte retrieval to avoid cyst manipulation and reduce infection risks while collecting surrounding follicles. Antibiotic prophylaxis may be required.

Should an endometrioma be surgically removed before starting IVF?

Routine surgical removal of endometriomas prior to IVF is generally not required unless the cyst causes severe pain refractory to medical management, exhibits atypical imaging characteristics, or physically blocks access to developing follicles. Because surgical excision carries a risk of reducing remaining ovarian reserve, non-surgical management is frequently favored prior to ovarian stimulation.

Does endometriosis increase the risk of implantation failure or early pregnancy loss during IVF?

Endometriosis is clearly associated with infertility, but the evidence that endometriosis itself causes implantation failure or early pregnancy loss during IVF is surprisingly weak and inconsistent. Overall live birth rates following the transfer of viable embryos in endometriosis patients remain favorable.

Although eutopic endometrium in women with endometriosis exhibits multiple molecular abnormalities—including progesterone resistance, altered decidualization and inflammatory signalling—the clinical relevance of these findings remains uncertain. Studies controlling for embryo competence through euploid blastocyst transfer have not demonstrated reduced implantation, live birth or increased pregnancy loss. Conventional IVF studies remain heterogeneous, with some showing modestly reduced clinical pregnancy or live-birth rates; however, these effects cannot readily distinguish ovarian/embryonic from endometrial mechanisms. Once pregnancy is established following IVF—particularly when embryo competence is controlled for—endometriosis alone does not appear to substantially increase the risk of early pregnancy loss.

Importantly, concomitant adenomyosis should be considered separately, as its association with impaired implantation and miscarriage appears substantially stronger. Endometriosis and adenomyosis frequently coexist, and older IVF studies did not always adequately distinguish between the two conditions. Therefore, part of the historically observed “endometrial effect” attributed to endometriosis may actually be driven by coexisting adenomyosis.

References

1. ESHRE Guideline Group on Endometriosis. ESHRE guideline: endometriosis. Human Reproduction Open. 2022;2022(2):hoac009.
2. Kohl Schwartz AS, Imboden S, von Wolff M. Endometriosis. In: von Wolff M, Nawroth F, eds. Fertility Preservation in Oncological and Non-Oncological Diseases: A Practical Guide. Springer Nature Switzerland AG; 2020:133-144.
3. Practice Committee of the American Society for Reproductive Medicine. Endometriosis and infertility: a committee opinion. Fertil Steril. 2012;98(3):591-598.
4. Practice Committee of the American Society for Reproductive Medicine. Treatment of pelvic pain associated with endometriosis: a committee opinion. Fertil Steril. 2014;101(4):927-935.
5. Bishop et al., Endometriosis does not impact live-birth rates in frozen embryo transfers of euploid blastocysts. Fertility and Sterility 2021; 115(2): 416-422

Disclaimer: This article is for general educational purposes only and does not constitute medical advice, formal diagnosis, or a treatment recommendation. Healthcare choices and clinical pathways must be determined in direct consultation with a licensed reproductive endocrinologist following a comprehensive, individualized medical assessment.

About the author

Dr Ewa Goncikowska, MD, PhD
Specialist in Gynaecological Endocrinology, Reproduction & Infertility