What it is (overview)

A Transvaginal Ultrasound Scan (TVS), also called a transvaginal ultrasound, is a type of diagnostic imaging test that uses high-frequency sound waves to create detailed pictures of the pelvic organs. Unlike an abdominal pelvic ultrasound (done over the tummy), TVS uses a slim ultrasound probe placed gently into the vagina. This position allows the scanner to get closer to the uterus, ovaries, cervix, endometrium (uterine lining), and nearby structures, so the images are usually clearer and more detailed.

TVS does not use radiation. The scan “measures” and assesses things such as the size and shape of the uterus and ovaries, the thickness and appearance of the endometrium, and the presence of fluid or growths (for example cysts or fibroids). In some situations, Doppler ultrasound may also be used to look at blood flow in pelvic vessels or within a mass.

What results can mean (in plain language): A report may describe the uterus and ovaries as normal, or it may identify findings such as an ovarian cyst, uterine fibroids, polyps, signs of inflammation/infection, or changes in the uterine lining. Results are interpreted together with your symptoms (such as pelvic pain or abnormal bleeding), your age, and where you are in your menstrual cycles. Many findings—like small functional cysts—can be common and may resolve on their own, while other findings may require follow-up scans, medication, or further testing (e.g., blood tests or biopsy) depending on the clinical situation.

When & why it's usually done

Doctors commonly order a TVS to investigate symptoms, monitor known gynecologic conditions, or guide decisions about treatment. Because it provides detailed views of the pelvic organs, it is often used as a first-line test for many concerns related to gynecological health.

A transvaginal ultrasound is usually done to help evaluate:

Symptoms

• Pelvic pain (sudden or ongoing), including pain that may be related to the ovaries or uterus
• Abnormal vaginal bleeding (heavy periods, bleeding between periods, bleeding after menopause)
• Irregular menstrual cycles or changes in period pattern
• Unusual pelvic pressure, bloating, or fullness
• Pain during sex (dyspareunia)
• Unusual discharge or symptoms that may suggest infection (when paired with exam and lab tests)

Common clinical reasons

• To identify or monitor ovarian cysts (simple/functional cysts or more complex cysts)
• To detect and measure uterine fibroids and see how they may affect the uterine cavity
• To assess the endometrial lining (for example, thickening, polyps, or causes of abnormal bleeding)
• To evaluate suspected endometriosis (including endometriomas) or possible causes of chronic pelvic pain
• To investigate possible causes of infertility and to monitor follicle development during fertility treatment (if applicable)
• To help assess early pregnancy concerns (such as pain or bleeding) and evaluate for possible complications when clinically indicated
• To check the placement of an IUD (intrauterine device) if strings are not felt or symptoms occur

What to expect: The scan is typically done in a clinic or imaging center and usually takes around 10–20 minutes. You may be asked to empty your bladder beforehand. Most people feel mild pressure rather than pain; let the sonographer know if you are uncomfortable. TVS is generally safe, but it may be deferred or adjusted in certain situations (for example, if you prefer an abdominal scan first or based on individual clinical circumstances).

Common diseases related to it

• Uterine fibroids (leiomyomas)
• Ovarian cysts (functional cysts, hemorrhagic cysts, complex cysts)
• Endometriosis (including ovarian endometriomas)
• Adenomyosis
• Polycystic ovary syndrome (PCOS)
• Endometrial polyps
• Abnormal uterine bleeding (AUB) and endometrial thickening
• Pelvic inflammatory disease (PID) and tubo-ovarian abscess (when suspected clinically)
• Ovarian torsion (urgent assessment when symptoms suggest it)
• Evaluation of pelvic masses (benign vs suspicious features) and follow-up of known lesions

Health goals where it may help

• Supporting overall gynecological health through timely evaluation of symptoms and reassurance when findings are normal
• Finding the cause of pelvic pain and guiding next steps in care
• Monitoring uterine fibroids or ovarian cysts over time to track growth or resolution
• Evaluating and managing irregular menstrual cycles or abnormal bleeding by assessing the uterus and endometrial lining
• Fertility planning and treatment monitoring (e.g., tracking follicles and uterine lining when recommended)
• Checking IUD position and confirming appropriate placement when symptoms arise
• Early assessment of pregnancy-related pelvic symptoms (pain/bleeding) when clinically indicated
• Planning treatment decisions (medical therapy vs procedures) by mapping fibroids, polyps, or other pelvic findings