Fallopian tubes are delicate structures that pick up the egg that has been released from the ovary. Fertilization also takes place in the fallopian tubes. When the tubes are blocked or when their mobility is restricted by adhesions stemming from previous infections or surgical procedures, the egg and sperm cannot meet and fertilization cannot take place. Adhesions or blocked tubes are usually due to infections most of which are sexually transmitted.

The infection may go unnoticed in 50% of the cases. Infections that affect the fallopian tubes are gonorrhea and chlamydia. The blocked tubes may be visible to ultrasound. However, more commonly they are detected by a hysterosalpingogram (x-ray of the uterus and fallopian tubes). Completely blocked tubes form a structure that is called a hydrosalpinx (fallopian tube filled with fluid). When there is partial blockage the diagnosis is more difficult the make and may require laparoscopy (visualization of the female internal genital organs by endoscopy).

Laparoscopy is also a means of opening blocked tubes or releasing adhesions that are the result of previous infections or surgery. Certain conditions are required prior to undertaking what we call reconstructive tubal surgery. If these conditions are met laparoscopic removal of adhesions and creating a new opening to the fallopian tubes may be successful in achieving a pregnancy. However, only a fraction of women with blocked tubes will benefit from surgery.

In most cases IVF treatment is the only option. It may be preferable to remove the blocked tubes if they are not amenable to surgery as these may decrease the success of IVF. Several mechanisms have been suggested as to why this happens. The most commonly accepted one is that the fluid that builds up in the tube intermittently refluxes into the endometrial cavity (inner lining of the uterus where the embryos will eventually implant thus dislodging the embryos that are transferred.