Introduction:
Abnormal uterine bleeding is a frequent gynecological issue across women of all ages. The causative factors of abnormal uterine bleeding can be both gynecological and non-gynecological. Earlier dilatation and curettage were the investigative methods for abnormal uterine bleeding, but they could not identify intrauterine lesions like polyps or fibroids.
What Is an Abnormal Uterine Bleeding?
Abnormal uterine bleeding (AUB) can be prolonged or heavy bleeding between the monthly periods. Abnormal uterine bleeding can be caused due to conditions like thyroid disease, anovulation (absence of ovulation), polyps, fibroids, malignancy, infections, or certain medications. The condition causing abnormal uterine bleeding can be diagnosed by transvaginal sonography, hysteroscopy, or histopathologic examination. Patients with AUB should be subjected to transvaginal sonography first, followed by hysteroscopy and a hysteroscopy-directed biopsy if necessary.
What Is a Transvaginal Sonography (TVS)?
Transvaginal sonography is a diagnostic method used to examine the uterus, ovaries, vagina, bladder, and fallopian tubes. In this procedure, a probe is inserted into the vaginal area, which causes sound waves to bounce off the organs inside the pelvic region. These sound waves create echoes that are picked up by the probe and are turned into a moving image called the sonogram. This moving image is displayed on a monitor of computer while the scan is carried out. Transvaginal sonography (TVS) can show the uterus and the endometrium (tissue lining the uterus) abnormalities in detail. Pathologies of the fallopian tubes, ovaries, and cervix can also be evaluated.
What Is Hysteroscopy?
Hysteroscopy is a method that allows the surgeon to look inside the uterus to diagnose and treat the causes of abnormal bleeding. Hysteroscopy is done using a hysteroscope. A hysteroscopy uses a lighted thin tube that is inserted into the vaginal area to examine the cervix and inside the uterus.
What Is a Histopathological Examination?
A histopathological examination is an examination of tissue specimens of the body done under a microscope to diagnose and study diseases of the tissues.
What Is the Role Of Transvaginal Sonography in Abnormal Uterine Bleeding?
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Transvaginal sonography is the first step in investigating the uterine cavity for abnormal uterine bleeding.
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This investigative method can diagnose endometrial polyps, uterine anomalies, submucous fibroids, adenomyosis (endometrium grows into the muscle walls of the uterus), and generalized endometrial thickening associated with hyperplasia (increase in the number of cells in an organ or tissue) and malignancy.
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Endometrial thickness seen by transvaginal sonography can be of three kinds. The secretory, proliferative, or abnormal endometrium depends on their thickness. The thickness can be related to the phase of menstruation.
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A proliferative endometrium describes a healthy reproductive cell activity and is not a symptom or condition. Sonographic examination findings are considered normal if a hyperechoic line was observed in the middle of the uterus along with the homogenous endometrial lining and district margin with the myometrium (smooth muscle tissue of the uterus). A proliferative endometrium appears smooth pale pink, and gland openings can sometimes be seen.
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In premenopausal (time before menopause) patients, the normal limits of the anteroposterior diameter of the endometrium were four to eight mm in the proliferative phase, eight to four mm in the secretory phase, and 6 to 10 mm in the periovulatory phase. A secretory phase endometrium is changes seen in the endometrium during the second half of the menstrual cycle when the endometrium is morphologically well prepared for implantation and development of the fertilized egg. A secretory phase endometrium can appear puffy and vascular. A periovulatory or follicular phase is when the layers of cells surrounding the egg begin expanding. An increase above the limits or any heterogeneous echogenicity was considered abnormal.
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In postmenopausal patients, a normal endometrium has a double wall thickness greater than five mm, which consists of a thin basal layer. It appears atrophic (decreased cell size) and avascular (lack of blood vessels).
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A thick endometrium noted by TVS can be due to pregnancy-related conditions, late secretory endometrium, endometrial polyp, hyperestrogenism (a condition with elevated estrogen levels), and malignancy which can all be present with abnormal uterine bleeding.
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A non-specific increase in the endometrial echogenicity or presence of any fluid in the endometrial cavity is also considered a non-specific abnormal finding.
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If a transvaginal scan shows a normal uterine cavity, further evaluation need not be done, and the patient can be started on medical treatments for her symptoms.
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Further evaluation with a hysteroscopy should be considered if the patient fails to respond to the medical treatment.
What Is the Role of Hysteroscopy in Abnormal Uterine Bleeding?
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Hysteroscopy done in abnormal uterine bleeding provides direct visualization of the uterine cavity and can guide the biopsy of any local lesion if present.
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Hysteroscopy can be carried out in an office, with or without minor anesthesia.
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It can also be performed in an operating room with general or regional anesthesia.
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In hysteroscopy, the appearance can be either normal or conditions like endometritis, uterine myoma, hyperplasia, or endometrial polyp.
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Although the management of abnormal uterine bleeding in hysteroscopy is diagnostic, there is also scope for simple operative procedures like targeted endometrial biopsy and polypectomy.
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It removes abnormal structures in the uterus, like fibroids or polyps.
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Some risks associated with hysteroscopy include uterine perforation, cervical laceration, infection, fluid overload, and creating false passages.
What Is the Role of Histopathological Examination in Abnormal Uterine Bleeding?
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A histopathological evaluation of the endometrial samples plays an important role in the diagnosis of endometrial pathology and in providing appropriate treatment.
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Endometrial evaluation is recommended for women in perimenopausal and postmenopausal age groups with abnormal uterine bleeding not responding to any medical treatment to rule out the possibility of any preneoplastic condition or malignancy. Hyperplasia and malignancies are commonly seen in the perimenopausal and postmenopausal age groups.
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In a histopathological examination of the endometrium, the normal cyclical pattern is the most seen in reproductive age and perimenopausal age groups, including the proliferative and secretory phase endometrium.
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The absence of uniform glandular development characterizes a disordered proliferative pattern (DPE), and it resembles a simple hyperplasia but is focal in the process rather than diffuse. A disordered proliferative pattern is high among the perimenopausal age group. It is important to diagnose DPE early to prevent the disease from progressing further.
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The second most common pattern is simple hyperplasia (increase in the number of cells in an organ or tissue) with or without atypia (irregular condition) and complex hyperplasia with or without atypia. These patterns have a variable progression risk to malignancy.
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Pathologists need to diagnose endometrial hyperplasia as they are the precursor for endometrial cancer.
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Another pattern is the Endometrial polyp, a benign outgrowth from the uterine cavity composed of stroma, glands, and blood vessels.
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Chronic endometritis is a chronic inflammation of the endometrium. It is characterized by inflammatory endometrium infiltrated by the plasma cells.
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Atrophic endometrium is due to estrogen deprivation in the menopausal period and rupture of dilated venules beneath the thin endometrium leading to abnormal uterine bleeding.
Conclusion:
Abnormal uterine bleeding is caused due to various conditions like polyps, pregnancy, fibroids, infections, or malignancy. Using techniques like transvaginal sonography, hysteroscopy, or histopathologic examination we can identify the causative factor or underlying pathology causing the bleeding so that early interventions can be done.
