Tubal blockage or tubal occlusion (the medical term) is the mechanism by which tubal ligation procedures prevent pregnancy. Tubal blockage prevents sperm from being able to reach an egg and also prevents eggs from being able to reach the uterus. When tubal sterilization is performed, tubal blockage is intentional. Tubal blockage also occurs due to disease conditions and results in involuntary infertility. Whether intentional or resulting from disease, tubal blockage can often be corrected with reconstructive tubal surgery.
Prevalence and Causes of Tubal Blockage
More than 10 million women in the US and 100 million worldwide have had a tubal sterilization. In the US alone, there are over 6 million infertile couples. Approximately 1 million of the cases of infertility are due to tubal disease. Most cases of tubal occlusion due to disease are caused by pelvic inflammatory disease (PID). PID is as an inflammatory condition of the fallopian tubes (salpingitis) and may also involve the ovaries (oophoritis), and pelvic peritoneum (peritonitis). In many, perhaps the majority of cases, PID is unrecognized or “silent”, and/or misdiagnosed. An authoritative medical text, Pelvic Inflammatory Disease has been published by Raven Press and edited by Dr. Gary S. Berger and Dr. Lars V. Westrom. Endometriosis is another condition that can cause tubal blockage and is sometimes confused clinicially with PID. Congenital abnormalities or malformations of the uterus and fallopian tubes may also result in tubal blockage. In these cases, the blockage is usually at the uterine, or proximal, end of the tube rather than at the fimbrial end as occurs with PID.
Treatments for Tubal Blockage
There are 2 basic approaches to treat infertility due to tubal blockage:
Tubal surgery is best performed by gynecologic reproductive surgeons who have specialized training and experience in this area. In Vitro Fertilization (IVF) in essence replaces the functions of the fallopian tube with laboratory and minor surgical procedures that result in fertilization and transfer of fertilized eggs or embryos into the uterine cavity.Since the advent of in vitro fertilization (IVF), reconstructive tubal surgery is becoming a lost skill. IVF is more popular than tubal surgery among reproductive endocrinologists.
Tubal Surgery to Correct Tubal Blockage
There are 3 primary techniques of tubal reconstructive surgery:
- Tubal Anastomosis– Tubal anastomosis involves removing the blocked segment of the tube and joining the two remaining open segments. It is also referred to as tubal reanastomosis or tubotubal anastomosis. This is the surgical treatment used when the tubal blockage is between the uterus and the fimbrial end of the tube.
- Tubal Implantation– Tubal implantation is used to correct a proximal tubal occlusion or blockage at the junction of the fallopian tube and uterus. The blocked segment is bypassed by creating a new opening in the uterus and inserting the healthy portion of the fallopian tube into the uterine cavity. Tubal implantation is also called tubouterine implantation or uterotubal implantation.
- Salpingostomy– Salpingostomy is creating a new opening in the fallopian tube. This operation, also called neosalpingostomy, is used to correct distal tubal occlusion at or near the fimbrial end of the tube caused by fimbriectomy, PID, or endometriosis.
Benefits and Risks of Tubal Surgery vs IVF
The primary benefit of tubal surgery to repair tubal blockage is that it is done once. After a tubal blockage is repaired, pregnancy can occur at any time after the surgical procedure. The primary risk of tubal surgery in an increased rate of tubal pregnancy. IVF has the advantage that it avoids surgery, but it is more complicated and requires the use of extremely large doses of hormones to stimulate the ovaries. This is called "super-ovulation". The use of super-physiologic doses of ovarian stimulating hormones is associated with the risks of ovarian hyperstimulation and an increased rate of multiple pregnancies.More about Tubal Blockage