Uterine abnormalities are structural variations that affect the uterus, the reproductive organ where a baby grows during pregnancy. These differences can impact how the uterus functions, potentially leading to various health concerns.
Understanding Different Types
Uterine abnormalities are broadly categorized into those present at birth, known as congenital or Müllerian duct anomalies, and those that develop over time, referred to as acquired abnormalities. Congenital abnormalities arise from issues during the formation and fusion of the Müllerian ducts in a female fetus. These ducts typically form the uterus, fallopian tubes, and part of the vagina.
Congenital uterine abnormalities include:
A septate uterus: A fibrous or muscular wall divides the uterine cavity, either partially or completely.
A bicornuate uterus: Often described as heart-shaped, results from incomplete fusion of the two sides of the uterus, leading to two horn-like projections.
An arcuate uterus: Involves a mild indentation at the top of the uterine cavity, considered a variation of normal development.
A unicornuate uterus: Only one half of the uterus develops.
Uterus didelphys: Involves two completely separate uteri, each with its own cervix and sometimes a double vagina.
Acquired uterine abnormalities develop later in life:
Uterine fibroids: Benign (non-cancerous) growths in the muscular wall of the uterus.
Endometrial polyps: Overgrowths of the tissue lining the inside of the uterus.
Adenomyosis: Tissue that normally lines the uterus grows into its muscular wall.
Asherman’s syndrome: Scar tissue forms inside the uterus, often from surgery or infection.
Signs and Diagnosis
Many uterine abnormalities do not cause noticeable symptoms and are often discovered incidentally during evaluations for other conditions. When symptoms are present, they can include chronic pelvic pain, which may worsen during menstruation, and abnormal uterine bleeding, such as heavy or irregular periods.
Some individuals may experience difficulty conceiving, known as infertility, or suffer recurrent pregnancy losses. These symptoms often prompt medical investigation. Healthcare professionals use various methods to diagnose uterine abnormalities.
Diagnostic methods include:
Transvaginal ultrasound: A common initial imaging technique providing detailed images of the uterus.
Magnetic Resonance Imaging (MRI): Offers a comprehensive view, useful for distinguishing congenital anomalies.
Hysterosalpingography (HSG): Involves injecting dye into the uterus and fallopian tubes to visualize their shape and patency using X-rays.
Hysteroscopy: A thin, lighted telescope is inserted through the cervix to view the inside of the uterus.
Laparoscopy: A minimally invasive surgical procedure to view the outside of the uterus and pelvic organs.
How They Affect Reproductive Health
Uterine abnormalities can impact reproductive health, influencing both the ability to conceive and the course of a pregnancy. These structural differences can create fertility challenges by interfering with conception. An altered uterine shape or reduced cavity size can make it difficult for sperm to reach the egg, for a fertilized egg to implant, or for an embryo to develop properly.
Once pregnancy is achieved, uterine abnormalities can lead to various complications. Recurrent miscarriage is a common risk, particularly with a septate uterus, due to inadequate blood supply in the septum. Ectopic pregnancy, where the fertilized egg implants outside the uterus, can occur. Individuals might also experience preterm birth or fetal malposition, such as a breech presentation, due to limited space within the uterus.
Placental complications, like placenta previa (where the placenta covers the cervix), can also arise. These effects stem from mechanisms such as altered uterine shape restricting fetal growth, reduced uterine cavity size limiting space, or impaired blood supply compromising placental function. A compromised endometrial lining, especially with Asherman’s syndrome, can also hinder implantation and early pregnancy development.
Available Treatments
Not all uterine abnormalities require intervention, especially if asymptomatic and not causing health or reproductive issues. For those who experience symptoms or reproductive challenges, treatment aims to alleviate discomfort, improve conception chances, or reduce pregnancy complications. Treatment decisions are individualized, considering the specific abnormality, symptom severity, and patient’s reproductive goals.
Observation is often the approach for asymptomatic cases, where regular monitoring is sufficient. Medical management, often involving hormonal therapy, can help manage symptoms associated with certain conditions, such as reducing heavy bleeding or pain caused by fibroids.
Surgical correction is an option for many structural abnormalities. Hysteroscopic septoplasty, for example, removes the dividing wall in a septate uterus, which can improve pregnancy outcomes. Myomectomy involves surgically removing uterine fibroids while preserving the uterus. Endometrial polyps can also be removed surgically, often through hysteroscopy.