Why Your Doctor Might Order a Transvaginal Ultrasound During Pregnancy

Sometime during your pregnancy, your doctor may order a transvaginal ultrasound examination for you. A transvaginal ultrasound is a test that uses high-frequency sound waves (ultrasounds) to create images of your internal organs. 

This type of ultrasound is an internal examination, since the word transvaginal means “through the vagina.” Regular pelvic ultrasounds use wands that rest on the outside of the pelvis, while a transvaginal procedure is performed by inserting an ultrasound wand a few inches into the vagina.

Both types of ultrasounds allow you to view the images on a monitor on the ultrasound machine to which wand is connected. A transvaginal ultrasound provides a better view of the female reproductive organs, including the uterus, ovaries, fallopian tubes, and cervix.

When performed during pregnancy, this type of ultrasound is typically used to determine the following:

• Help provide a more accurate due date for some women
• Check for ectopic pregnancy (tubal pregnancy)
• Determine the cause of pelvic pain or bleeding
• Check for cysts, particularly in the ovary
• Look for an early fetal heartbeat
• Examine the placenta for any abnormalities
• Assess the uterine lining
• Assess the uterus or ovary
• Check the cervix for any changes that could lead to miscarriage or premature delivery
• A possible miscarriage

The images from a transvaginal ultrasound are just as good as other types of ultrasounds. In fact, this exam is likely to provide better photos early on because the ultrasounds do not have to travel through the abdomen and the wand is closer to the uterus, giving you the best early pictures. The exam is used most frequently before the eighth week of pregnancy.

To undergo this exam, you may be visiting a diagnostics center where a technician performs the ultrasound, or your doctor may perform the test in the clinic. Either way, you will most likely be given a hospital gown to wear, as clothes from the waist down will have to be removed.

Next, you will lie down on an examination table, place both feet in the stirrups while your doctor or a technician covers the ultrasound wand with a condom and lubricating gel before inserting the wand into your vagina.

This type of ultrasound is not painful, but some women may feel some pressure from the wand. The procedure doesn't hurt as much as a vaginal exam. The entire test should take somewhere between 30 to 60 minutes. 

Your doctor may provide you with a series of instructions prior to your appointment. For example, particular reasons for the ultrasound may require that your bladder be full or empty (a full bladder lifts the intestines and your pelvic organs can be better viewed). A full bladder will require that you drink a considerable amount of water, about 30 mins before your appointment. If you have been spotting, you’ll have to remove your tampon before the ultrasound can take place.

If your doctor performs your ultrasound, then you will probably get your results immediately following the examination. If it is a technician that is performing the ultrasound, then the images must first be analyzed by a radiologist before the results are sent to your doctor for review.

Results typically take 24 hours to come in, but if a clear picture wasn't obtained, you may have to go back to repeat the procedure. Your doctor will then talk to you about your results and course of treatment or action if anything is found in the ultrasound images.