Does endometriosis affect In Vitro Fertilization (IVF) outcomes?

Does Endometriosis Affect IVF Outcomes?

Yes, endometriosis does negatively impact IVF outcomes, with the severity of disease determining the extent of impairment—stage III/IV (moderate to severe) endometriosis significantly reduces implantation rates, clinical pregnancy rates, and cumulative live birth rates compared to minimal/mild disease or tubal factor infertility. 1, 2

Impact by Disease Severity

Stage I/II (Minimal/Mild) Endometriosis

• Fertilization rates are modestly reduced (RR = 0.93,95% CI 0.87-0.99), representing approximately a 7% decrease compared to women without endometriosis 1
• Implantation and clinical pregnancy rates remain comparable to other infertility etiologies 3, 4
• Cumulative pregnancy rates after fresh and frozen embryo transfers are similar to women with tubal factor infertility 3

Stage III/IV (Moderate/Severe) Endometriosis

• Implantation rates are significantly reduced (RR = 0.79,95% CI 0.67-0.93), representing a 21% decrease 1
• Clinical pregnancy rates per fresh embryo transfer are markedly lower at 22.6% compared to 40.0% in stage I/II disease and 36.6% in tubal infertility 2
• Cumulative live birth rates after 1-4 IVF cycles are substantially worse at 40.3% compared to 55.8% in stage I/II endometriosis 2
• Fertilization potential of oocytes is impaired even in the absence of male factor infertility, suggesting intrinsic oocyte quality defects 4

Endometrioma-Specific Considerations

• Women with endometriomas may present with reduced ovarian reserve markers, including decreased antral follicle counts (<5 follicles) and ovarian volume (<3 cm³) 5
• Up to 44% of women experience symptom recurrence within one year after surgery, potentially leading to progressive ovarian damage 5
• Endometriosis affects at least one-third of women with infertility 5

Clinical Algorithm for IVF in Endometriosis Patients

Step 1: Assess disease severity and ovarian reserve

• Perform transvaginal ultrasound to identify endometriomas, measure antral follicle count, and assess ovarian volume 6
• Consider MRI pelvis if deep infiltrating endometriosis is suspected or if surgical planning is needed 6

Step 2: Counsel on prognosis based on disease stage

• Stage I/II: Reassure that IVF outcomes are comparable to other infertility causes 3, 4
• Stage III/IV without deep infiltrating disease: Counsel on reduced implantation and pregnancy rates but reasonable cumulative success 1, 2
• Stage III/IV with deep infiltrating disease: Discuss significantly lower cumulative pregnancy rates and consider surgical consultation 3

Step 3: Proceed with IVF as first-line treatment

• IVF is recommended for women with endometriosis because pregnancy rates, while reduced in severe disease, remain acceptable and align with international ART society guidelines 3
• Consider transferring two embryos in stage III/IV disease given lower implantation rates, though this must be balanced against multiple pregnancy risks 2

Step 4: Surgical considerations

• The question of whether to surgically resect deep infiltrating endometriosis (stage III/IV) before IVF remains unresolved, but cumulative pregnancy rates are significantly lower in this subgroup 3
• Laparoscopy is reserved for definitive treatment rather than diagnosis, as empiric treatment can be initiated based on clinical and imaging findings 7

Critical Pitfalls to Avoid

• Do not assume normal imaging excludes endometriosis—superficial peritoneal disease is poorly detected by all imaging modalities and may still impact IVF outcomes 7
• Do not delay IVF in favor of prolonged medical management in women with documented endometriosis and infertility, as progressive ovarian damage may occur 5
• Do not underestimate the impact of stage III/IV disease—these patients require realistic counseling about reduced success rates and may need multiple IVF cycles 2
• Do not overlook ovarian reserve assessment—women with endometriosis may have diminished reserve that further compromises IVF success 5

Mechanistic Understanding

The biological basis for reduced IVF success in endometriosis involves multiple pathways 8:

• Impaired oocyte quality due to the inflammatory pelvic environment 4
• Reduced fertilization potential even when fertilization occurs outside the pelvis 1, 4
• Compromised endometrial receptivity affecting implantation 1
• Progressive ovarian damage from recurrent disease 5