Stage I–II Endometriosis — Limited Anatomic Impact
Small implants rarely block the tubes but still hurt fertility.
- ~25–40%: Prevalence in infertile women (have some endometriosis)
- ~4–5%: Monthly fecundity, Stage I–II (vs ~20% in fertile couples)
- +9pt: Laparoscopic excision benefit (pregnancy rate over 9 months)
- 1–15: ASRM classification points (defines Stage I–II range)
What mild disease looks like
Superficial peritoneal implants, minimal scarring.
Why fertility still drops
Local inflammation impairs egg pickup and quality.
The ENDOVIS/ SEE trials found excision nearly doubles spontaneous pregnancy rate at Stage I–II.
First-line approach
Laparoscopic excision, then try naturally for 6–12 months.
Stage III–IV Endometriosis — Distortion & Endometriomas
Deep lesions and cysts scramble normal pelvic anatomy.
- ~1–2%: Monthly fecundity, Stage III–IV (markedly reduced)
- ~35%: Endometrioma prevalence (of Stage III–IV cases)
- −30–40%: AMH drop after cystectomy (ovarian tissue loss risk)
- up to 50%: Tubal blockage risk (in severe adhesive disease)
Anatomic distortion
Adhesions fuse ovary, tube, and bowel together.
Endometrioma dilemma
Removing cysts can also remove healthy ovarian tissue.
Surgeons weigh pain relief and access against reserve loss before cystectomy.
Planning ahead
Reserve testing before surgery guides how aggressive to be.
Ovarian Reserve — AMH and the Fertility Window
AMH and age together estimate remaining egg supply.
- 1.5–4.0: Normal AMH range (ng/mL, reproductive age)
- <1.0: Low reserve threshold (ng/mL AMH)
- ~50%: AMH decline per decade (independent of endometriosis)
- complementary: Antral follicle count use (to AMH for reserve staging)
What AMH measures
Anti-Müllerian hormone reflects the small growing follicle pool.
Age still matters most
Egg quality declines with age even when AMH looks fine.
Endometrioma surgery can accelerate the normal age-related AMH decline.
Using both together
Age sets the clock; AMH estimates remaining ticks.
Surgery vs IVF — Matching Pathway to Patient
Younger patients with good reserve may try surgery first.
- age <35: Surgery-first candidates (+ good ovarian reserve)
- age >37: IVF-first candidates (or low AMH)
- 6–12 mo: Time-to-pregnancy, surgery (natural conception window)
- 2–3 mo: Time-to-pregnancy, IVF (per stimulation cycle)
Surgery-first logic
Restore anatomy, then allow natural conception attempts.
IVF-first logic
Bypass distorted anatomy when time or reserve is limited.
Shared decision-making weighs age, reserve, pain, and patient preference together.
Combined strategy
Some patients do surgery, then IVF if pregnancy is delayed.
Treatment Outcome — Comparing Pregnancy Rates
Neither pathway is universally superior; context decides.
- ~40–50%: Cumulative live birth, IVF (per 2–3 cycles, age <35)
- ~30–50%: Cumulative pregnancy, surgery (Stage I–II, within a year)
- additive: Surgery + later IVF (benefit reported in cohorts)
- age × AMH: Key deciding factor (not stage alone)
Reading the comparison
Bars update live as stage and age sliders change.
When outcomes converge
Mild disease and young age make both pathways similar.
Severe disease plus advancing age tends to favor IVF over repeat surgery.
Bottom line
Individualized counseling beats a one-size-fits-all protocol.