Transvaginal Ultrasound

What is Transvaginal Ultrasound?

Transvaginal ultrasound is a diagnostic radiological procedure that helps in understanding the structures of the female pelvic organs like uterus, cervix and ovaries and shows up any abnormal growth within these organs. Transvaginal sonogram, when done during pregnancy, gives information about the formation and growth of the fetus and the surrounding areas.

Other terms used for the Transvaginal ultrasound are:

• Transvaginal ultrasonography
• Transvaginal sonogram
• Endovaginal ultrasound

The procedure of transvaginal ultrasound is done by inserting a probe or transducer inside the vagina, usually covered with a new and sterile condom. The ultrasound waves travel across the vaginal wall to study the tissues and organs beyond it.

The sonography images of a transvaginal ultrasound give information about the structures of the uterus, growing fetus if any, abnormal growth in the uterus, other reproductive organs like cervix, ovaries etc and also position of the intrauterine devices used for contraception.

High frequency sound waves are emitted by a probe that is inserted into the vagina. These sound waves bounce off the surrounding internal organs, creating images of their structures. These sonogram images can be seen on a monitor.

Transvaginal ultrasound differs from abdominal ultrasound in terms of the placement of the probe. Also, the structures viewed are clearer in transvaginal sonogram.

Why is Transvaginal Ultrasound Performed?

The following conditions are the indications for a transvaginal ultrasound procedure:

• Abdominal examination
• Checking for cysts, polyps or fibroids in the uterus

• Unexplained vaginal bleeding
• Infertility
• Checking the position of intrauterine devices
• Examining the lining of uterus for conditions like endometrial atrophy (thinning of the inner lining of the uterus), adhesions or scarring
• Identifying cancers or benign tumors in the pelvic region

Transvaginal ultrasound during pregnancy can give information about:

• Confirmation of early pregnancy
• Estimated date of delivery if the woman is not sure about the first day of last menstrual cycle
• Presence of multiple pregnancies
• Presence of any ectopic pregnancy

• The baby's gestational age
• The yolk sac and amniotic fluid
• Fetal heartbeat
• Cervical problems that could lead to complications such as premature delivery or miscarriage
• Source of any abnormal bleeding
• Fetal birth defects
• Problems of the placenta, uterus, cervix and ovaries
• Placental position and to rule out anterior placenta

Preparing for a Transvaginal Ultrasound Procedure

The woman undergoing a transvaginal sonogram would need to undress from the waist down for the procedure, though the feet and legs will be covered with a sheet.

A little discomfort may be felt and some women report a mild pain after the procedure. However, probe insertion can be made easier if the woman is relaxed. Taking deep breaths when probe is being inserted can help relax.

The procedure can be done even during the menstrual cycle or during any spotting. However, if a tampon is in place, it has to be removed before the test.

Procedure of Transvaginal Ultrasound

The examinee is made to lie on her back on the testing table, with the knees bent and feet placed in stirrups. The probe will be covered with a condom, which in turn will be lubricated with gel. This probe is inserted into the vagina, and may be moved a little to see the pelvic organs.

The sound waves that bounce off the internal organs are transmitted to a computer. These waves create images that are seen on the monitor.

The examination typically takes about 15 to 30 minutes. The doctor will move the probe a little inside the vagina to get different views of the pelvic organs. The doctor may note down some readings and store some images for future reference.

Saline Infusion Transvaginal Ultrasound (SIS)

This procedure is a slight modification of the regular transvaginal ultrasound. The indication for Saline infusion transvaginal ultrasound is any suspected abnormality of the uterine cavity and abnormal vaginal bleeding. The procedure involves the following steps:

• A speculum is placed in the vagina to view the cervix (opening of the uterus).
• The cervix is cleaned with a disinfectant and a small catheter is inserted in the uterus.
• The ultrasound probe is placed in the vagina.
• A small amount of sterile fluid is inserted into the uterus through the catheter, while the probe sends ultrasound waves and records the images of the uterus.
• The required images are stored in the computer and are ready to be analyzed by the doctor.

The moving fluid in saline infusion transvaginal ultrasound helps in providing better images of the uterine cavity and its lining, than the conventional transvaginal ultrasound.

Some women may experience cramping or spotting during or after the procedure. Sometimes, pain killers may be prescribed by the doctor. This procedure is not done during pregnancy.

Who does the Procedure of Transvaginal Ultrasound?

Most of the time, the gynecologist performs the transvaginal ultrasound procedure for specific problems in women and for pregnant women. Sonographers may perform the procedure in the presence of the family doctor or gynecologist, so that they may specify if any particular readings or images need to be noted and stored for future reference.

Sonographers are health professionals who are specially qualified to perform sonography procedures of various sites of the body. The procedure is usually performed in the radiology department of the hospital. The examination is performed in privacy of a room that may be dimly lit for the examiner to see the images more clearly on the screen.

Significance of Results of Transvaginal Ultrasound

The readings and images noted down during the procedure of transvaginal sonogram could reveal a lot of information about the structure, pathophysiology and abnormalities in the pelvic organs.

Possible Abnormal Results of Transvaginal Ultrasound

• Birth defects
• Tumour or cancer of the uterus, vagina, ovaries or any other pelvic structures
• Pelvic inflammatory disease or any other infections in the region
• Cysts, polyps or fibrosis in or around the uterus and ovaries
• Twisting of ovaries or fallopian tubes

Normal Results of the Transvaginal Ultrasound during Pregnancy

6-8 weeks of pregnancy: The gestational sac is seen along with the growing embryo and yolk sac. Heartbeat may or may not be detected during this period. The doctor can check for and also the length of the cervix.

8-10 weeks of pregnancy: Heartbeat of the baby and the amount of fluid around the baby is more clearly seen. The area around the gestational sac is examined by the doctor.

10-12 weeks of pregnancy: Head, body and limbs are obvious in the sonogram images obtained during 12th week of pregnancy. Abdominal ultrasound is usually performed at this stage, but some doctors may use transvaginal method also. The estimated date of delivery is usually given at this stage after taking the measurements of the baby.

When is the Test Results Revealed?

The results of the test may be announced immediately or kept aside for senior doctors to comment on them. The waiting time for receiving the written report depends on:

• Urgency of the result needed
• Information provided by the doctor to the sonographer or radiologist
• Expert doctor comments requirement
• Complexity of the exam
• Requirement of the results being conveyed to personal doctor or gynecologist from the radiology department

Contraindications of Transvaginal Ultrasound

There are no known risks of transvaginal sonography as there is no radiation involved. However, the following conditions are contraindications for the procedure.

• Premature rupture of amniotic sac
• Abnormally low lying placenta

References:

1. Transvaginal ultrasound - (http://www.nlm.nih.gov/medlineplus/ency/article/003779.htm)
2. Sonohysterography - (https://www.radiologyinfo.org/en/info.cfm?pg=hysterosono)
3. About Transvaginal Ultrasound - (https://www.cedars-sinai.edu/Patients/Programs-and-Services/Imaging-Center/For-Patients/Exams-by-Procedure/Ultrasound/Transvaginal-Ultrasound.aspx)