Asherman Syndrome

Asherman syndrome (intrauterine adhesions, intrauterine synechiae) is the formation of fibrous bands within the uterine cavity or cervical canal, partially or completely obliterating the cavity, after damage to the basal layer of the endometrium.

The commonest cause is trauma to a gravid or recently gravid uterus: curettage for miscarriage, termination or retained products (about 90 percent), especially 2 to 4 weeks after delivery when the endometrium is hypoestrogenic. Other causes are caesarean section, myomectomy, hysteroscopic surgery, uterine artery embolisation, endometritis (genital tuberculosis and schistosomiasis in endemic areas), and radiation.

Incidence after dilatation and curettage for miscarriage is 15 to 30 percent, rising with repeated procedures. Basal endometrium is replaced by scar, and hormonal response is impaired.

• Menstrual abnormality: hypomenorrhoea (most common), oligomenorrhoea or amenorrhoea with normal FSH and normal ovarian function.
• Cyclic pelvic pain occurs when functioning endometrium lies proximal to an obstructing cervical adhesion (cryptomenorrhoea, haematometra).
• Infertility and recurrent miscarriage, because adhesions interfere with implantation and placentation.
• Obstetric complications in established pregnancy: preterm labour, abnormal placentation (accreta, praevia), retained placenta and postpartum haemorrhage, and fetal growth restriction.
• Examination is usually normal; a uterine sound may stop short in the cavity.
• Severity is graded by extent: mild (thin filmy adhesions), moderate (dense adhesions with partial cavity obliteration), severe (cavity largely obliterated, tubal ostia occluded, amenorrhoea).

• Exclude pregnancy and other causes of amenorrhoea after a procedure: hCG, FSH, LH, prolactin and TSH are normal. A progestogen challenge (medroxyprogesterone 10 mg daily for 10 days) gives no withdrawal bleed, and a combined oestrogen progestogen challenge also fails to give a bleed in severe disease.
• Hysteroscopy is the gold standard: direct vision and simultaneous treatment; adhesions are classified as filmy, fibromuscular or dense connective tissue; the cavity and ostia are scored.
• Hysterosalpingography shows irregular multiple filling defects with fixed margins; saline infusion sonography and three dimensional ultrasound are alternatives; MRI is used when the cervix is obstructed.
• Where tuberculosis is suspected, endometrial biopsy for acid fast bacilli, culture and PCR; chest X-ray.

Treatment is hysteroscopic adhesiolysis, with prevention of re-formation and restoration of the endometrium.

• Hysteroscopic adhesiolysis under direct vision using scissors, microscissors or electrodes (cold dissection preferred, to avoid thermal injury to the remaining endometrium).
• Separate adhesions starting from the lowest part at the cervical os and progress upward to the fundus, restoring the cavity and visualising both tubal ostia. In dense disease, laparoscopic or ultrasound guidance reduces the risk of uterine perforation.
• Post-operative anti-adhesion measures: intrauterine balloon (Foley catheter size 8 to 10 or a purpose designed balloon) for 5 to 7 days, hyaluronic acid gel instilled at the end of the procedure, and no intrauterine device with a copper surface.
• Oestrogen therapy to promote regrowth of endometrium: estradiol valerate 2 to 4 mg orally daily (up to 6 mg in severe cases) for 30 to 60 days. Add medroxyprogesterone acetate 10 mg daily or dydrogesterone 10 mg twice daily for the last 10 days to induce a withdrawal bleed. Thromboprophylaxis is considered in women at risk.
• Prophylactic antibiotics at the time of surgery (cefazolin 1 g single dose, or doxycycline 100 mg twice daily for 5 days when infection risk is high).
• Second look hysteroscopy at 1 to 2 months to check cavity and divide recurrent adhesions; repeat until the cavity is normal. Recurrence of adhesions occurs in 3 to 25 percent, higher in severe disease (up to 60 percent).
• Genital tuberculosis: standard four drug antituberculous therapy for 6 months (isoniazid, rifampicin, pyrazinamide, ethambutol for 2 months followed by isoniazid and rifampicin for 4 months); adhesiolysis is of limited benefit once endometrium is destroyed.
• Refractory endometrial failure: autologous platelet rich plasma, stem cell therapy and G-CSF are experimental; gestational surrogacy may be the only option.
• Outcomes: normal menstruation returns in 70 to 90 percent. Pregnancy rates are 60 to 80 percent in mild to moderate disease and 20 to 40 percent in severe disease.
• Pregnancies need early ultrasound and delivery planning because of accreta, praevia, preterm birth and postpartum haemorrhage.
• Prevention: avoid sharp curettage after miscarriage and use medical (misoprostol) or suction methods. Perform procedures under ultrasound or hysteroscopic guidance when possible, and manage retained products hysteroscopically.