All About Your Fallopian Tubes

Where They Are, How They Work, and What Happens When They Are Blocked

Illustration of the female reproductive system, with the fallopian tubes clearly labeled
Fertilization of the egg takes place inside the fallopian tube. BruceBlaus / Wikicommons / CC BY

Quick Definition:

The fallopian tubes are two thin tubes, one on each side of the uterus, which help lead the mature egg from the ovaries to the uterus. If conception takes place, the egg is usually fertilized in the fallopian tube. Then, the fertilized egg, or embryo, makes its way through the tube, and eventually implants into the uterine lining.

Sometimes, the fertilized egg will attach itself to the fallopian tube instead of the uterus.

This results in an ectopic pregnancy.

IUI and IVF treatment increase the risk of ectopic pregnancy. 

Causes of Infertility Related to the Fallopian Tubes

Blocked fallopian tubes are a common cause of infertility in women.

If the egg and sperm cannot meet, you can't get pregnant without fertility treatment.

An HSG -- a special kind of x-ray -- is used to see if the fallopian tubes are clear.

If the fallopian tube is infected and fluid filled, it is known as a hydrosalpinx. 

Getting "your tubes tied" is a form of permanent birth control and involves cutting or clamping the fallopian tubes shut, preventing pregnancy. This is known as tubal ligation. 

Sometimes, tubal ligation can be reversed through surgery. Blocked fallopian tubes can also sometimes be opened via surgery.

But these procedures are not always successful.

In those cases, conception is only possible with IVF treatment.

The Anatomy and Physiology of the Fallopian Tube

The fallopian tubes are muscular structures. They are not just stationary tubes of tissue but moving and active organs of the reproductive system.


They are usually between 7 and 12 cm in length and less than 1 cm in diameter. The diameter of the tube on the inside varies depending on where in the tube you are. 

Where the fallopian tube connects with the uterus, it is extremely narrow: just 1 millimeter across. 

The fallopian tubes are widest in the section where fertilization is most likely to take place. There, it is approximately 6 millimeters in diameter. 

The fallopian tube is made up of three sections:

  • the isthmus: this is the section closest to the uterine opening
  • the ampulla: this is the middle section where fertilization takes place
  • the infundibulum: this is the section near the ovaries

While the fallopian tubes are directly connected to the uterus, they do not connect directly to the ovaries. 

At the far end of the fallopian tube, fingerlike projections known as fimbriae encourage an ovulated egg to come inside the fallopian tube. 

The inside of the fallopian tubes are lined with small hair-like projections known as cilia. These cilia help move an ovum or fertilized egg towards the uterus.


Fertility Treatment and the Fallopian Tubes

If the fallopian tubes are blocked or missing, in vitro fertilization (IVF) treatment may be needed to conceive.

IVF treatment bypasses the need for the fallopian tubes. During IVF, fertility drugs are used to stimulate the ovaries to develop many oocytes (eggs).

These eggs are then retrieved during a procedure known as an egg retrieval. The eggs retrieved are put together with sperm in petri dishes in an embryology lab. 

If sperm fertilize the egg and create an embryo, those embryos can then be transferred directly into the uterus. 

Two lesser known fertility treatments are GIFT and ZIFT. They require at least one fallopian tube to be healthy and unblocked.

GIFT stands for Gamete Intrafallopian Transfer. Gametes are egg and sperm, and intrafallopian means inside the fallopian tube. 

During the assisted reproductive technology treatment GIFT, the eggs and sperm are placed within the fallopian tube, in hopes that fertilization will take place in the same area that natural conception occurs.

This treatment is most often used for couples who religion forbids traditional IVF treatment. With IVF, conception occurs outside the body in the lab. During GIFT, conception occurs inside the body, in the fallopian tubes.

ZIFT stands for Zygote Intrafallopian Transfer. During ZIFT, an already fertilized egg is released in the fallopian tube.

ZIFT and GIFT are not commonly done.

More on female reproduction:

More on causes of infertility:

Continue Reading