For many women, the menstrual cycle is a regular rhythm of life, and the ability to conceive is often taken for granted. When this rhythm is disrupted, periods become extremely light or stop altogether, or when desired pregnancies end in loss, it can be a confusing and emotionally painful experience. While hormonal issues are often suspected, these symptoms can sometimes be due to a lesser known, acquired physical condition called Asherman’s syndrome. This disorder, characterized by the formation of scar tissue inside the uterus, is a significant but often treatable cause of infertility and menstrual disruption. Understanding what Asherman’s syndrome is, how it develops, and the advanced ways it can be treated offers hope to the many women affected by it.

Asherman’s syndrome is an acquired condition where adhesions, or bands of scar tissue (also known as synechiae), form inside the cavity of the uterus and/or the cervix. These adhesions are not normal tissue; they are tough, fibrous bands that can bind parts of the uterus together, significantly impacting its structure and function.

To understand this better, it’s helpful to have a picture of a healthy uterus. The inner lining of the uterus, called the endometrium, can be thought of as two walls covered in a soft, plush, and highly vascular lining. Each month, under the influence of hormones, this lining thickens in preparation for a potential pregnancy. If pregnancy does not occur, this lining sheds, resulting in a menstrual period. In Asherman’s syndrome, significant uterine injury causes raw, opposing surfaces inside the cavity. As the body heals, these raw surfaces can stick to one another, forming scar tissue.

These scar tissue bands can range in severity:

• They can be thin and flimsy, like cobwebs.
• They can be thick and dense, like strong bands.
• In severe cases, the adhesions can be so extensive that they cause the front and back walls of the uterus to fuse together, partially or completely obliterating the uterine cavity.

This scarring has profound consequences. It can physically block the opening of the fallopian tubes, preventing sperm from reaching an egg. It can also cover and destroy the healthy endometrial lining.

Analogy: Imagine the inside of the uterus like a balloon lined with soft velvet. In Asherman’s Syndrome, parts of that lining are stuck together with internal scarring, like tape binding the velvet, preventing it from expanding or functioning normally.

The single underlying cause of Asherman’s syndrome is significant trauma or injury to the uterine lining, specifically to its deep basal layer. The endometrium has two main layers: a functional layer, which thickens and sheds each month, and a deeper basal layer, which acts as the “mother layer” responsible for regenerating a new functional layer after each period. A normal period or a gentle uterine procedure does not damage this crucial basal layer.

Asherman’s syndrome occurs when this basal layer is aggressively scraped away or destroyed by injury, infection, or surgery. When the basal layer is gone, the body cannot regenerate the normal, soft lining. Instead, it heals by forming scar tissue, much like how deep damage to the skin results in a scar rather than perfect new skin. This scarring process is most likely to occur in a recently pregnant uterus, which is softer, more vascular, and in a low-estrogen state that can impair normal healing.

Patients often report that their periods changed after a specific procedure, but no one connected the dots until fertility testing later revealed a severely scarred uterine cavity.

Asherman’s syndrome is an acquired condition, it develops as a direct consequence of a specific event that causes significant uterine trauma.

The most common initiating events include:

1. Dilation and Curettage (D&C): This surgical procedure is, by far, the most common cause of Asherman’s syndrome worldwide. A D&C involves dilating the cervix and using an instrument called a curette to scrape the uterine lining. While it is a necessary and common procedure, it carries a risk of causing deep trauma, especially in certain situations:

• Postpartum or Post-Miscarriage D&C: The risk of developing Asherman’s is highest when a D&C is performed on a recently pregnant uterus, for example, to remove retained placental tissue after childbirth or a miscarriage. In this state, the uterine walls are soft and the lining is not protected by high levels of estrogen, making it more vulnerable to aggressive scraping.
• Infected Uterus: Performing a D&C when an infection is present (endometritis) can exacerbate the inflammation and lead to more severe scarring.

2. Other Uterine Surgeries: Any surgery that involves cutting into the uterine cavity can potentially lead to adhesions. This includes:

• Myomectomy: Surgical removal of uterine fibroids, especially those located within the uterine cavity.
• Cesarean Section: While less common, complications from a C-section, such as difficult placental removal or infection at the incision site, can lead to scarring.

3. Severe Uterine Infections: In some cases, a severe infection of the endometrium (endometritis) can cause enough damage to the basal layer to trigger adhesion formation, even without a surgical procedure. Genital tuberculosis, while rare in many Western countries, is a known cause of severe Asherman’s syndrome in other parts of the world where TB is more prevalent.

4. Other Rare Causes: Less common causes include uterine artery embolization (a procedure to treat fibroids), endometrial ablation (a procedure to destroy the uterine lining to treat heavy bleeding), and the placement of an intrauterine device (IUD) that leads to a severe, chronic infection.

Clinically, we often see Asherman’s Syndrome in women who’ve had multiple D&Cs or complications after childbirth, especially if menstruation became irregular afterward.

The symptoms of Asherman’s syndrome depend on the severity of the adhesions. Some women may have only subtle menstrual changes, while others face infertility or pregnancy loss.

The most common symptoms include:

• Menstrual Irregularities: This is the hallmark of the condition.
  • Hypomenorrhea: Periods that become very light, scanty, or short.
  • Amenorrhea: The complete absence of menstrual periods.
  • Normal Periods with Severe Pain: In some cases, if the scarring is located only at the cervix, it can block the outflow of menstrual blood. A woman may experience normal cyclical cramping and PMS symptoms but see little or no blood flow, a condition known as cervical stenosis.
• Infertility: The inability to conceive is a major symptom for many women seeking help. This can be because sperm cannot reach the egg, or because the scarred uterine lining is unable to support the implantation of an embryo.
• Recurrent Pregnancy Loss: Some women with Asherman’s syndrome are able to conceive, but the pregnancy ends in miscarriage. This happens because the scarred lining cannot provide the adequate blood supply and support needed for the placenta and fetus to grow and thrive.
• Cyclical Pelvic Pain: As mentioned, some women experience pain at the time of their expected period due to trapped blood.

Diagnosis

Diagnosis requires a high level of clinical suspicion, especially in women with menstrual irregularities or infertility following uterine procedures.

The diagnostic process involves imaging the inside of the uterine cavity:

• Transvaginal Ultrasound: This is often a first step but cannot definitively diagnose Asherman’s. It may show a very thin endometrial lining, which can be a clue, but it cannot directly visualize the scar tissue.
• Saline Infusion Sonohysterography (SIS or SHG): This is an enhanced ultrasound where a small amount of sterile saline is infused into the uterus. The fluid helps to separate the uterine walls, allowing the doctor to see adhesions and scar tissue more clearly as irregularities within the fluid-filled cavity.
• Hysterosalpingogram (HSG): This is an X-ray procedure where a special dye is injected into the uterus. The dye fills the cavity and fallopian tubes. On the X-ray, adhesions will appear as “filling defects” areas where the dye cannot go because scar tissue is in the way.
• Hysteroscopy: This is the gold standard for diagnosing Asherman’s syndrome. It is a minimally invasive procedure where a surgeon inserts a very thin, lighted camera (a hysteroscope) through the cervix and directly into the uterus. This allows the surgeon to see the inside of the uterine cavity in high-definition video.

Treatment

The treatment for Asherman’s syndrome is a specialized surgical procedure called operative hysteroscopy or adhesion lysis. The goal is to carefully cut and remove scar tissue, restoring the normal size and shape of the uterine cavity.

The Surgical Procedure: This procedure is performed by a highly skilled gynecologic surgeon with expertise in hysteroscopy. Using the hysteroscope to see inside the uterus, the surgeon inserts tiny instruments, such as microscopic scissors or lasers, to meticulously cut the bands of scar tissue. The goal is to do this with minimal damage to any remaining healthy endometrium. This is a delicate procedure requiring significant expertise.

Post-Operative Care: Removing the adhesions is only half the battle. The postoperative period is critical for preventing the scar tissue from immediately growing back as the raw surfaces heal. The standard post-operative protocol includes:

• Placement of a Uterine Stent or Balloon: Temporarily placed after surgery to keep the uterine walls from sticking back together.
• Hormone Therapy: Estrogen therapy is commonly given after surgery to promote endometrial healing and regrowth. Followed by progesterone to restore a normal cycle.
• Follow-up Hysteroscopy: A second-look hysteroscopy is often performed a few weeks or months after the initial surgery to ensure the cavity has healed well and to remove any minor adhesions that may have started to reform.

Pregnancy outcomes after successful treatment depend on the initial severity of the disease and the health of the remaining endometrium, but many women are able to conceive and carry a pregnancy to term.

Asherman’s syndrome is a significant and distressing condition, representing a physical injury to the uterus that can lead to infertility and recurrent pregnancy loss. It is a stark reminder of the potential complications of common gynecological procedures, especially D&C. However, it is also a condition for which there is hope. With an accurate diagnosis via hysteroscopy and meticulous surgical treatment by a skilled specialist, the scar tissue can be removed. The subsequent hormonal and preventative care is just as crucial to ensure the womb has the best possible chance to heal and recover its function. If you’ve noticed changes in your period after a procedure, or are struggling with unexplained infertility, it’s worth asking your doctor about Asherman Syndrome. Early detection and treatment offer the best chance of full recovery.

• American Society for Reproductive Medicine (ASRM). (2012). Intrauterine scarring. Retrieved from https://www.reproductivefacts.org/news-and-publications/patient-fact-sheets-and-booklets/documents/fact-sheets-and-info-booklets/intrauterine-scarring/
• American Society for Reproductive Medicine. (2023). Asherman Syndrome. https://www.asrm.org
• National Institutes of Health (NIH), Genetic and Rare Diseases Information Center (GARD). (n.d.). Asherman’s syndrome. Retrieved from https://rarediseases.info.nih.gov/diseases/5852/ashermans-syndrome