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Home >  SERVICES > Fertility Investigation > 3D/4D Saline Infused Sonography (SIS) and Hysterosalpingo Contrast Sonography (HyCoSy)

3D/4D Saline Infused Sonography (SIS) and Hysterosalpingo Contrast Sonography (HyCoSy)3D/4D Saline Infused Sonography (SIS) and Hysterosalpingo Contrast Sonography (HyCoSy)

What is 3D and 4D SIS and HyCoSy?

Hysterosalpingo Contrast Sonography (HyCoSy) is a special ultrasound test using contrast “dye” to show whether your fallopian tubes are open. Saline Infused Sonography (SIS) uses a saline solution and ultrasound to check the shape and lining of the uterus. These investigations help us to understand why women may suffer from infertility or miscarriage and will help us decide what appropriate treatments or further investigations should be offered.

How are the scans done?

The scan is carried out as an outpatient procedure and takes about half an hour. A routine transvaginal scan may be carried out first by placing a vaginal scan probe inside the vagina. This checks the position of the uterus and ovaries. A speculum is then placed in the vagina (like a smear test). A small tube (catheter) is passed through the cervix into the uterus and a syringe is attached to the outside end of the tube with the saline or “dye”. Using the ultrasound probe to see, a small amount of fluid is then passed through the catheter into the uterus to outline the uterine cavity and the fallopian tubes.

Will it hurt?

When the tube is inserted into your cervix you may feel some discomfort but this often wears off quite quickly. Not all patients feel this. When the “dye” is injected you may feel a “period type” pain. This pain may last for up to two hours after the procedure and you should rest at home until this passes. If you do experience discomfort after the test you may contact your doctor regarding taking some simple painkillers e.g. paracetamol or non-steroidal anti-inflammatory drugs (NSAID). Some patients can sometimes also feel faint after the procedure and may need to rest for a while before going home. It is advisable therefore to bring someone with you to accompany you home.

When should I not have the test?

The test should be performed during the first 10 days of the cycle. You should not have the test if you are on your period. You should also not have unprotected intercourse from your period until the test. It is important that we do not do the test if there is a chance you might be pregnant. Also inform your doctor if you have had a previous sexually transmitted disease (e.g. Chlamydia) as you may require antibiotics to undergo the procedure.

What are the risks of these investigations?

  • If you are pregnant: The procedure could harm a developing baby.
  • Infection: The risk of an infection following the procedure is less than 1 in 100 cases. Prophylactic antibiotics will be routinely given to reduce any risk.
  • Allergy: It is extremely rare to have an allergic reaction to the “dye” but if you have any known allergies you should inform your doctor prior to the procedure.

PLEASE NOTE: If you have any problems after the test such as high fever or persistent offensive vaginal discharge, please contact your doctor for advice