Endometriosis: Ectopic Implants and Chronic Pain

Endometriosis is a chronic, estrogen-dependent inflammatory disease characterized by the presence of tissue resembling the endometrium outside the uterine cavity. Ectopic implants — most common on the ovaries (endometrioma), pelvic peritoneum, uterosacral ligaments, and cul-de-sac — bleed with each menstrual cycle, causing progressive local inflammation, adhesions, and fibrosis. It affects 10% of women of reproductive age (176 million worldwide) and is underdiagnosed: the average diagnostic delay is 7–10 years.

10%
PREVALENCE IN WOMEN OF REPRODUCTIVE AGE
176 million affected worldwide
7–10 years
AVERAGE DIAGNOSTIC DELAY
chronically underdiagnosed disease
30–50%
INFERTILE WOMEN WITH ENDOMETRIOSIS
leading cause of female infertility
70%
HAVE CHRONIC PELVIC PAIN
beyond menstrual dysmenorrhea

Conventional Treatments: Hormonal Therapy and Surgery

Conventional treatment of endometriosis is based on two pillars: hormonal suppression (to reduce estrogenic stimulation of the implants) and surgical removal by laparoscopy. Both strategies have important limitations, making complementary treatments such as acupuncture relevant in clinical practice.

CONVENTIONAL TREATMENTS VS. ACUPUNCTURE

TREATMENTEFFICACY ON PAINLIMITATIONS
NSAIDs (ibuprofen, naproxen)Moderate relief of dysmenorrhea (VAS −2.1 pts); insufficient for severe dysmenorrheaChronic use: GI, renal risk; does not treat the underlying disease
Combined oral contraceptive (continuous)Reduces bleeding and dysmenorrhea by 60–70%Contraindications (DVT, migraine with aura, smoking >35 years); hormonal side effects; pain returns on discontinuation
Hormonal IUD (levonorgestrel)Reduces dysmenorrhea and pelvic pain by 70–80%; effective in mild-moderate endometriosisNot available to all; painful insertion; not indicated in young nulliparous women by some protocols
GnRH agonists (leuprolide)Induces pseudomenopause; excellent for pre-surgical usePharmacological menopause: hot flashes, bone mass loss; maximum 6 months; high cost
Ablative laparoscopyRemoves implants and adhesions; improves pain and fertilityInvasive; recurrence 40–50% in 5 years; risk of ureteral, bowel injury; postoperative adhesions
AcupunctureVAS −3.2 pts dysmenorrhea; −2.8 pts chronic pelvic pain; reduces PGE2 by 34%Does not remove implants; sustained benefit requires maintenance; access and cost

How Acupuncture Works in Endometriosis

Proposed mechanisms for the effect of acupuncture on endometriosis include segmental pelvic analgesia, possible modulation of uterine prostaglandins, control of central sensitization, and effects on the neuroimmune pathway. No isolated mechanism explains the clinical effect, and the extrapolation of experimental findings to clinical outcomes remains under investigation.

Mechanisms in Endometriosis

  1. Inhibition of Prostaglandin Synthesis

    SP-8 (Xi Cleft of the Spleen) activates inhibitory interneurons in the dorsal horn of T10–L1 (pelvic segments), reducing uterine nociceptive transmission. Electroacupuncture at 2 Hz at this point reduces PGE2 and PGF2α in the endometrium — the prostaglandins responsible for the painful uterine contractions of dysmenorrhea.

  2. Segmental Pelvic Analgesia

    CV-4 and CV-6 (lower midline) activate somatic afferents from level T12–L1, inhibiting the pelvic spinal segment. SP-6 (in TCM, Spleen governs the uterus and pelvic organs) modulates visceral afferents via the tibial nerve (S2–S4), converging on the same spinal neurons that receive uterine pain.

  3. Modulation of the Immune-Inflammatory Axis

    Endometriosis is an inflammatory disease: implants activate peritoneal macrophages and elevate IL-6, TNF-α, and VEGF. Acupuncture (ST-36, SP-10, LI-11) reduces systemic IL-6 and TNF-α — a relevant mechanism for chronic pelvic inflammation.

  4. Control of Central Sensitization

    With chronic pain (months to years), central sensitization occurs — the central nervous system amplifies all painful signals. Acupuncture modulates NMDA and reduces the expression of spinal c-fos, gradually desensitizing the central pain system that sustains chronic pelvic pain.

Main Points in the Treatment of Endometriosis

SP8 — Xi Cleft of Spleen (Point of Choice for Dysmenorrhea)

The Xi Cleft is the energy-accumulation point of the meridian — used specifically for acute pain in the corresponding organ. SP8 is the most studied point for dysmenorrhea: 2 Hz EA during the attack reduces pain in 40–60 minutes, with effect documented by reduction of serum PGE2.

LR3 — Traditional Context and Neural Correlate

In the tradition of Chinese medicine, endometriosis is described in terms of 'stagnation of Qi and Xue' in the lower abdomen — the domain of the hepatic channel. Biomedically, LR3 is located over the deep fibular nerve; studies suggest an association with the release of β-endorphin and activation of descending pain inhibition pathways.

ST29 — Guilai (Ovarian Point)

ST29 is located 2 cun lateral to CV4, above the inguinal canal. Its stimulation activates somatic afferents that converge with ovarian afferents at the L2L3 segment — useful especially for ovarian endometrioma pain and pre-ovulatory pain.

SP6 — Three Yin (Crossing of SP, LR, KI)

SP6 is the crossing point of the three Yin meridians of the leg (Spleen, Liver, Kidney) and the gynecological point par excellence in Chinese medicine. It activates the convergence of S2S4 afferents (via the tibial) and T10L1 — fundamental for chronic uterine pain.

Scientific Evidence

The evidence base for acupuncture in endometriosis has grown significantly in the last decade. A Cochrane systematic review (2021) identified 10 RCTs with n=660 patients, concluding that acupuncture reduces the intensity of dysmenorrhea and chronic pelvic pain with a moderate effect size (SMD −0.72).

Modern Approach: Integration with Conventional Treatment

Acupuncture in endometriosis is most effective when integrated with conventional treatment in a multimodal strategy. The medical acupuncturist defines the role of acupuncture according to the clinical picture: predominantly for dysmenorrhea, chronic pelvic pain, dyspareunia, or fertility support.

Pre-Laparoscopy

Reduces pain while the patient awaits surgery. Does not delay or compromise surgery — surgeons report that acupuncture does not alter the operative field. May reduce the need for postoperative opioids.

With Hormonal Therapy

Fully compatible with the pill, hormonal IUD, or GnRH agonists. In the initial months of GnRH agonist — when hot flashes are intense — acupuncture for hot flashes can be associated.

When Hormonal Therapy Is Not an Option

For patients who refuse or have contraindications to hormonal therapy — adolescents, perimenopause with contraindications, short-term pregnancy planning — acupuncture can be considered as a complementary option for pain control, always together with gynecological follow-up. It does not replace medical evaluation and treatment of endometriosis.

When to See a Medical Acupuncturist

Priority Indications

Dysmenorrhea VAS >6 not controlled with NSAIDs; chronic pelvic pain for >3 months; dyspareunia that impacts quality of life; endometriosis in pregnancy planning (without desired hormonal suppression); post-surgical complement to maintain relief.

When to Include in the Plan

Awaiting laparoscopy (surgical wait list); contraindication or intolerance to hormonal therapy; endometriosis + anxiety/depression (acupuncture acts on both); endometriosis in adolescence (fewer side effects than hormones in development).

Frequently Asked Questions

FREQUENTLY ASKED QUESTIONS · 04

Frequently Asked Questions

No. Acupuncture does not remove endometriotic implants — that requires laparoscopic surgery. Acupuncture treats the symptoms of endometriosis: it reduces dysmenorrhea, chronic pelvic pain, and dyspareunia through analgesic and anti-inflammatory mechanisms. The benefit is real and documented, but it is symptomatic — not curative of the underlying disease.

Yes. Acupuncture is fully compatible with oral contraceptives, hormonal IUD, GnRH agonists, and progestins. There is no pharmacological interaction. In practice, many patients with endometriosis on the pill seek acupuncture for additional control of residual chronic pelvic pain — which persists even with the hormone.

For acute dysmenorrhea, acupuncture performed during the attack can bring relief in 30–60 minutes. For chronic pelvic pain, 4–6 weeks of weekly treatment are expected for sustained effect. Response varies according to the stage of endometriosis, the presence of central sensitization, and the history of previous surgeries.

Prospective studies suggest potential benefit in patients with endometriosis undergoing IVF: improved uterine flow, reduction of the pelvic inflammatory environment, and improved oocyte quality. The medical acupuncturist and the assisted reproduction specialist work together — the acupuncture protocol is adjusted to the phases of the IVF cycle.

Related Articles