The fallopian tubes are muscular tubes that are lined with delicate hair-like structures. These "hairs" work in both directions; helping an egg to travel from the ovaries down to the womb (uterus) and helping sperm travel up from the womb.
Each fallopian tube ends in fimbriae, which are finger-like structures. The fimbriae catch and guide an egg when the ovary releases it.
The fallopian tubes play an important role in conception because they are where most eggs are fertilized.
If any part of the fallopian tube is damaged, for example by surgery or an infection, they can become blocked by scar tissue.
Fallopian tubes connect the ovaries to the uterus and play an important role in fertility.
Blocked fallopian tubes do not often present symptoms other than difficulty conceiving. Doctors typically class this as having tried to conceive for 1 year without success.
A blocked fallopian tube may cause some women to experience symptoms such as pain in the pelvis or belly. This pain might happen regularly, such as around the time of their period, or be constant.
Sometimes, a blockage in a fallopian tube can cause a fertilized egg to get stuck. This is known as an ectopic pregnancy.
An ectopic pregnancy may not always cause symptoms and is usually detected during a scan. However, some woman may experience signs of pregnancy, such as stomach pain on one side of the body, or vaginal bleeding. Any woman who suspects she has an ectopic pregnancy should seek immediate medical attention.
Fallopian tubes can become blocked for a range of reasons, which include:
- a history of pelvic infection
- a previous burst appendix
- having had a sexually transmitted disease, such as gonorrhea or chlamydia
- endometriosis, a condition that causes the lining of the womb to grow outside of the uterus
- history of abdominal surgery
- hydrosalpinx, which is swelling and fluid at the end of a fallopian tube
All of these conditions can affect the fallopian tubes directly or this area of the body. In most cases, these conditions or procedures create scar tissue that can block the tubes.
Effects on fertility
A blocked fallopian tube may make getting pregnant difficult.
The female reproductive system is made up of the ovaries, uterus, and fallopian tubes.
If a medical problem has affected any of these three areas, it may make getting pregnant more difficult.
Each of the two ovaries is connected to the uterus by a fallopian tube. The ovaries store eggs and release them randomly, with one ovary releasing an egg each month.
For example, the right ovary might release an egg for 3 months in a row, and then the left ovary might release an egg the following month.
If one fallopian tube is blocked, it may still be possible for an egg to be fertilized. If both are blocked, this is less likely.
Blocked fallopian tubes can be difficult to identify. The tubes can open and close, so it is not always easy to tell if they are blocked or just closed.
There are three key tests to diagnose blocked fallopian tubes:
- An X-ray test, known as a hysterosalpingogram or HSG. A doctor injects a harmless dye into the womb, which should flow into the fallopian tubes. The stain is visible on an X-ray. If the fluid does not flow into the fallopian tubes, they may have a blockage.
- An ultrasound test, known as a sonohysterogram. This is very similar to the HSG test but uses sound waves to build up a picture of the fallopian tubes.
- Keyhole surgery, known as a laparoscopy. A surgeon makes a small cut in the body and inserts a tiny camera to take pictures of the fallopian tubes from inside.
A laparoscopy is the most accurate test for blocked tubes. However, doctors may not recommend this test as an early diagnosis because it is invasive and cannot treat the issue.
A doctor may be able to suggest a possible diagnosis based on medical history. For example, a woman may have had a burst appendix in the past. If the woman has had difficulty conceiving, this could suggest blocked fallopian tubes as a likely cause.
Treatment and surgery
It may be possible to open blocked fallopian tubes surgically. However, this depends on the extent of the scarring and where the blockage is.
Surgery aims to open the fallopian tube using one of the following methods:
- removing scar tissue
- making a new opening on the outside of the fallopian tube
- opening the fallopian tube from the inside
Most surgeons will carry out the procedure using keyhole surgery.
Blocked fallopian tubes and pregnancy
In some cases, IVF may be recommended when surgery is unsuccessful.
Surgery aims to open the fallopian tubes to improve a woman's chance of conceiving. Whether or not a woman will be able to conceive after surgery is affected by:
- her age
- the health of her partner's sperm
- the level of fallopian tube damage
If surgery is unsuccessful, a doctor may recommend in vitro fertilization (IVF). IVF involves placing fertilized eggs directly into the womb, which means that the fallopian tubes are not involved in pregnancy.
Surgery to open the fallopian tubes carries the same potential complications as any surgery. These include:
- creation of more scar tissue
- damage to organs
However, keyhole surgery is relatively low-risk.
One risk of pregnancy after surgery is an ectopic pregnancy, meaning that a fertilized egg gets stuck outside of the womb, often in a fallopian tube. The egg will not develop, and there can be a risk to a woman's health.
Women who have tubal surgery should see a doctor as soon as they find they are pregnant to check for an ectopic pregnancy.
When planning a pregnancy, it can be a good idea for a person to think about their medical history. This can include risk factors for blocked fallopian tubes, such as whether a woman has had surgery in this area of her body or a relevant infection. These considerations may help to diagnose a possible cause of infertility.
The outlook for fertility is considered to be reasonably good if only one tube is affected or scarring is minimal. If surgery to treat blocked fallopian tubes is not successful, IVF might be an option.