Tubal flushing is when a doctor uses a liquid medium to pass fluid under pressure through the fallopian tubes to ensure that these structures are open or patent.
A hysterosalpingogram (known as an HSG) is a form of X-ray that can be used to document tubal flushing. More intensive tubal flushing is often performed by a fertility specialist at the time of a diagnostic laparoscopy. It is a common part of the diagnostic process for women having difficulty becoming pregnant.
Why flush the fallopian tubes?
The fallopian tubes are the area of the female reproductive system where egg and sperm meet and where fertilization normally occurs. The embryo then cleaves in its first cell divisions as it travels down the pathway of the fallopian tube, only to reach the uterine cavity and implant to form a pregnancy five to six days later (at the blastocyst stage of development). Women whose fallopian tubes are completely and irreversibly blocked cannot become pregnant naturally and require IVF to conceive. If fallopian tubes are partially blocked then the chances of becoming pregnant are much reduced.
Sometimes the fallopian tubes are seriously damaged and completely blocked by processes such as advanced endometriosis, or scarring from a serious infection (e.g.Chlamydia). Sometimes however, fallopian tubes may be partially blocked by small cobweb like adhesions, mucous or cellular debris. It is in these cases (often where infertility is otherwise unexplained) that tubal flushing may help.
How is tubal flushing performed?
At a laparoscopy, a small tube is passed through the neck of the womb and fluid is introduced under gentle pressure. Flow through the fallopian tubes is observed using a 4mm fibre-optic camera (usually through a key hole incision at the umbilicus (belly button). Flushing can be repeated at laparoscopy for as long as is required and the fluid can be aspirated using a suction irrigation device. Flushing the tubes at an HSG has more limitations. As the woman is uncomfortable, and the procedure is not performed under anaesthetic, only a small amount of fluid can be tolerated. An HSG is a diagnostic flush, whereas treatment at laparoscopy can be a therapeutic flush – a tool used to clear partially blocked fallopian tubes. An HSG exposes a woman to a small dose of radiation whereas a laparoscopic flush does not. An HSG achieves a single purpose whereas a diagnostic laparoscopy with tubal flushing can address other fertility concerns simultaneously (for example, diagnosis and treatment of peritoneal endometriosis).
What kind of fluid is used to flush the fallopian tubes?
A few different kinds of fluids have been used to flush the fallopian tubes with proported benefits. The simplest of these is normal saline or in other words sterile salty water. Some doctors use indigo carmine or methylene blue dye while others use lipiodol or purefied popyseed oil. In ultrasound guided tubal flushing, levovist or exemfoam contrast is used.
What is the evidence for tubal flushing?
In 2015, a Cochrane review summarised 13 randomized controlled trials on tubal flushing. The reviewers found that women who had oil soluble tubal flushing had a higher rate (actually double the rate) of subsequent pregnancy than women who did not have a flush at all. There hasn’t really been a great deal of quality research comparing the relative benefits of flushing with various different mediums (e.g. salty water versus poppy seed oil).
What is the cost difference?
In Australia currently, purefied medical grade poppy seed oil can cost up to $400 (AUD) for a 10ml vial. This has no PBS funding and patients need to purchase the lipiodol as an out of pocket cost. Tubal flushing with sterile saline however is relatively inexpensive and may also be effective. An advantage of lipiodol is it may remain in the tubes, with effects that last for longer as it is not water soluble. A disadvantage is the possibility of allergic reaction or the complication of being absorbed into the bloodstream. There are no significant side effects or allergy risks to flushing the fallopian tubes with sterile saline.
Dr Raelia Lew offers patients with unexplained infertility the treatment option of fallopian tubal flushing with a choice of saline or lipiodol media.