The inner lining of the womb is called the endometrium and in a normal menstrual cycle it thickens in the luteal phase of the cycle to allow the implantation of an embryo. The uterine cavity is like a deflated balloon, where the front and back walls are in contact with each other, waiting to receive an embryo and to expand as the embryo grows. Asherman’s Syndrome refers to bands of adhesions (scar tissue) which form between these walls and thereby prevent implantation. These bands of adhesions may occur following trauma after surgery or infection (endometritis). The damage to the lining of the uterus could be classified as mild, with thin bands of adhesions, or severe with thick bands. Asherman’s can affect part of the uterine cavity or, in severe cases, the majority of it. Mild Asherman’s Syndrome may not be noticeable to the patient but the severe variety usually presents with the patient having light periods or a complete absence of them.
The causes for Asherman’s Syndrome are most commonly related to the removal of the products of conception following a miscarriage or abortion, or retained parts of the placenta following delivery. It can also occur following the hysteroscopic removal of endometrial polyps or the resection of fibroids in the uterine cavity. And endometrial ablation, which is a surgical procedure to destroy the lining of the womb with an intention to decrease heavy menstrual cycles, can also lead to Asherman’s Syndrome.
Diagnosis of Asherman’s Syndrome
Clinical presentation of light or no menstrual bleeding following a surgical intervention or following infection should raise suspicions. Patients undergoing IVF treatment and with recurrent implantation failure should also undergo a screening test to exclude intrauterine adhesions. An ultrasound examination called saline infusion sonography (Aquascan – see details) can easily demonstrate the presence of adhesions. Sometimes an HSG, which is an X-ray to assess tubal patency, may report the presence of adhesions in the uterine cavity.