Transvaginal ultrasound

What is a transvaginal ultrasound?

An ultrasound is a type of scan carried out by a sonographer which uses high-frequency sound waves to create a picture inside your body. A transvaginal ultrasound looks specifically at female productive organs including the uterus, cervix, and vagina, by passing the scanner through the vagina.

What does it involve?

A transvaginal ultrasound is an internal examination. Many people are familiar with an ultrasound scan which involves passing a microphone over the stomach to see inside the womb. With a transvaginal ultrasound, the microphone is gently fed through the vagina.

You’ll be asked to lie on your side or on your back with your knees drawn up for the procedure, and you might need to wear a hospital gown. You’ll be able to see the images in real time on a monitor, but the sonographer will also take some still pictures to analyse later. The examination should take about 15-30 minutes.

Transvaginal ultrasound is a safe procedure and there are no side effects.

Why is it done?

In pregnancy, a transvaginal ultrasound can be used to:

• detect development in the uterus at an earlier stage than a traditional (transabdominal) ultrasound
• identify or rule out issues such as miscarriage or an ectopic pregnancy, where the baby is developing outside the uterus
• look for signs of early labour

A transvaginal ultrasound might also be ordered if you have:

• pelvic pain or an abnormal pelvic exam
• unexplained vaginal bleeding
• difficulty getting pregnant

How to prepare

You don’t need to do any special preparations for a transvaginal ultrasound, other than emptying your bladder before the exam.

What does it feel like during the test?

The examination is not painful but might be slightly uncomfortable as the microphone is moved around. The microphone is much slimmer than those used in external ultrasound examinations. It is about the size of a finger, and it is covered with a condom and lubricating gel. You will be able to put it in yourself if you prefer to. After the exam you will be free to go home straight away.

What do abnormal results mean?

If an abnormal growth is found within the ovaries or uterus, there are a number of things that this could be. Fibroids, a type of benign tumour that can cause abdominal pain, are extremely common. Ovarian cysts are also common, and most go away without treatment. In some cases, however, a tumour might indicate ovarian cancer.

Other issues that can be detected with a transvaginal ultrasound include ectopic pregnancy and a low-lying placenta, which may or may not need to be treated. The results of the scan should be available within 1 or 2 weeks, and you will be able to discuss them with the doctor who ordered the scan. If a tumour is found inside your ovaries, the doctor is likely to order a biopsy to find out what kind of tumour it is.