Transvaginal Scan (TVS)
A transvaginal scan is done by inserting a probe or transducer into your vagina.
Sound waves emitted from the probe bounce off your baby and are captured by the probe again to produce a magnified image of your baby on a computer screen. This magnified image allows your doctor to determine if all is well with your pregnancy.
On an average the scan will take about 15 to 20 minutes.
If your doctor wants you to have a scan earlier than 10 weeks of pregnancy, you might have a transvaginal scan. This is because in early pregnancy, your baby is too small and too low in your abdomen to be seen clearly by an abdominal scan. A transvaginal scan allows your doctor to see into your uterus via the vagina.
You’ll most likely be offered an early scan when you’re between six weeks and 10 weeks pregnant if you:
- have a history of miscarriage
- have a history of ectopic pregnancy
- have had fertility treatment
- are in pain
- or have bleeding
After 10 weeks and for the rest of your pregnancy, you will have abdominal scans because once your uterus expands and moves up in your abdomen, your baby becomes more visible through your tummy. You might get a transvaginal scan if:
- You have a history of preterm labour and your doctor wants to check your cervix (mouth of uterus and birth canal).
- You are overweight, and an abdominal scan cannot deliver clear images.
- Your doctor suspects you have a low lying placenta, called placenta praevia.
Depending on when in your pregnancy it takes place, a TVS can be used to:
- Detect your baby’s heartbeat
- See whether you’re pregnant with one or more babies
- Check that your pregnancy is progressing normally in the uterus
- Evaluate the reason for any abdominal pain, spotting or bleeding
- Rule out an ectopic pregnancy
Many women find a vaginal scan more comfortable than an abdominal one, because you don’t need a full bladder during the procedure!
You will need an empty bladder for this scan because a full bladder can get in the way of a clear picture of your baby. A nurse will ask you to use the restroom while you are waiting for your scan.
You will also need to undress from the waist down for a TVS. It’s a good idea to wear two-piece clothing such as a salwar kameez or a long top with comfortable pants or slacks so you won’t need to get fully undressed. You’ll only need to remove the lowers, and you can continue to wear your top or kurta during the scan.
Once you have undressed from the waist down, the nurse will ask you to lie on your back on the ultrasound bed.
She will cover your legs with a sheet and ask you to raise your knees while keeping the soles of your feet flat on the bed. You will need to keep your legs apart so that the doctor has enough room to perform the scan. This position is somewhat similar to the one you take when you have an internal examination.
The doctor will cover the probe with a new and sterile latex sheath that looks like a condom. She will apply gel on the probe to ease its passage into your vagina and to get better clarity of the images. She will then insert about two to three inches of the probe into your vagina and perform the scan.
You might feel awkward and uncomfortable at the idea of a TVS but the more you relax, the easier it will be for the ultrasound doctor to insert the probe.
If your muscles are tense, it can be anything from uncomfortable to painful. Try taking in deep breaths when the probe is being inserted to help you relax.
Sometimes a heartbeat is seen in one sac, but not the other. Repeating the scan in a week or two may reveal a second heartbeat. However, the scan may show that one sac is growing and the other is still empty. This is known as vanishing twin syndrome.
The amount of fluid around his body becomes more obvious at this stage. Your doctor will also carefully examine the area around the gestational sac for any bleeding that can occur at this stage. This is sometimes called a subchorionic hematoma or haemorrhage, and is usually small area of bleeding next to the sac, like a bruise.
A small hematoma usually disappear on its own: it may be reabsorbed by the body or it comes away naturally as a vaginal discharge. If you are bleeding, your doctor may suggest you take some rest, although there’s little evidence this makes a difference.
If your muscles were tense during the scan, they might be sore or bruised.
You might feel a bit uncomfortable or even have a little spotting after the scan. Spotting can happen if a few small blood vessels of the cervix broke during the scan. This spotting is usually pink or brown in colour and is nothing to worry about.
However, if you have heavy and bright red bleeding along with cramps in your lower abdomen, contact your doctor immediately.