The Tubal Connection

The fallopian tubes project out from each side of the body of the uterus and form the passages through which the egg is conducted from the ovary into the uterus. The fallopian tubes are about 10cm long and the outer end of each tube is funnel shaped, ending in long fringes called fimbriae. The fimbriae catch the mature egg and channel it down into the fallopian tube when released by the ovary. The tube itself is a muscular highly movable structure capable of highly coordinated movement. The egg and sperm meet in the outer half of the fallopian tube called the ampulla. Fertilization occurs here, after which the embryo continues down the tube towards the uterus. The uterine end of the tube, called the isthmus, acts like a sphincter, and prevents the embryo from being released into the uterus for 2- days, so that it enters the uterus at just the right time for implantation. The tube is much more complex than a simple pipe, and the lining of the tube is folded and lined with microscopic hair like projections called cilia which propel the egg and embryo along the tube. The tubal lining also produces a fluid that nourishes the egg and embryo during its journey in the tube.

Tubal disease

Tubal abnormalities account for between 25% and 50% of female infertility. Tubal damage usually occurs through pelvic infection, and this is called pelvic inflammatory disease (PID). Often, we cannot find out the cause for the inflammation. However, some of the causes of pelvic infection that can be pinpointed are:

Sexually transmitted diseases (e.g. Gonorrhea, Chlamydia);
Infection after childbirth, miscarriage, termination of pregnancy (MTP) or IUD (intrauterine device) insertion
Post-operative pelvic infection (e.g. perforated appendix, ovarian cysts);
Severe endometriosis
Tuberculosis
Besides causing blocked tubes, any pelvic inflammatory disease can also produce bands of scar tissue called adhesions, which can alter the functioning of the fallopian tubes. PID can be a silent disease, and most women with tubal damage because of PID are completely unaware that they have this disease.

Pelvic tuberculosis is a fairly common cause of tubal damage in India. The tuberculosis bacteria reach the tubes from the lungs through the bloodstream and can cause irreparable tubal damage.

Making a Diagnosis of Tubal Diseases

A number of tests are available to judge whether or not the tubes are open.

The simplest and oldest test for tubal patency is the RT or Rubin's test named after its inventor. In this test, gas is passed under pressure into the tubes through the cervix and uterus - either with a special machine (Rubin's apparatus) or with an ordinary syringe. The doctor then listens with a stethoscope placed on the abdomen to determine if he can hear the sound of gas passing through the fallopian tube. Even though this test is now obsolete, because it is so unreliable, a number of doctors still do it.

Blood tests for chlamydial antibodies: Since an infection with chlamydia is the commonest reason for tubal disease in the West, some doctors test the blood for antibodies against chlamydia. Women who have antibodies against chlamydia have been exposed to this infection in the past, and are considered to be at higher risk for tubal damage.

Hysterosalpingogram (Uterotubogram) or HSG is a specialized X-ray of the uterus and tubes. An HSG is done after the menstrual flow just stopped usually on Day 6 or 7 of the period, at which time the lining of the uterus is thin. It is done in an X-ray. The patient is advised to take an antibiotic and a painkiller before the procedure by many doctors. After being positioned on the X-ray table, the doctor places a special instrument into the cervix, called a cervical cannula, which is made of metal. Many doctors now prefer to use a balloon catheter, as this makes the procedure less painful. A radio-opaque dye (a liquid which is opaque to X-rays) is then injected into the uterine cavity. This is done slowly under pressure, and pictures are taken - preferably under an image intensifier. The passage of the dye into the uterine cavity and then into the tubes and from there into the abdomen can be seen, and X-ray pictures taken. These provide a permanent record.

At least 3 films need to be taken to provide a reliable record - including an early film for the uterine cavity and a delayed film to make sure the spill of the dye in the abdomen is free.

A normal HSG defines the inside of the reproductive tract. This appears as a triangle (usually white on a black background), which represents the uterine cavity; and from here the dye enters the tubes that appear as two long thin lines, one on either side of the cavity. When the dye spills into the abdomen from a patent (open) tube, this appears as a smudge in the X-rays.

An abnormal HSG may show a problem in the uterine cavity - and this appears as a gap or filling defect. However, the commonest problems on HSG appear in the tubes. If the tubes are blocked at the cornual end (at the uterotubal junction), then no dye enters the tubes and they cannot be seen at all. If the block is at the fimbrial end then the tubes fill up; but the dye does not spill out into the abdominal cavity and the end of the tubes are often swollen up.

Sometimes, like any other medical test, the HSG may provide erroneous results. For example, the cornu of the uterus may go into spasm, as a result of which the dye may not enter the tubes at all. This may be interpreted as a tubal block, whereas in reality the tubes are open. Also, if a hydrosalpinx is very thin and if the dye is injected under pressure, the dye may appear to spill into the abdomen through a tear in the wall of the hydrosalpinx - suggesting tubal patency when really the tubes are closed.

While the HSG is usually very reliable for determining whether or not the tubes are open, it provides little information on structures outside the tube which could nevertheless impair tubal function - such as peritubal adhesions. If the spill is "loculated", (i.e. it collects in small puddles), the presence of adhesions can be suspected, but not confirmed.

An HSG can be painful and when the dye is injected into the uterine cavity, most women will experience a considerable amount of pain. You should be prepared for this - and taking a painkiller prior to the procedure will help to reduce the pain.

An HSG can be technically difficult for some women (especially if the cervix is too small or too tight) - and it is better if a gynecologist is present at the time of the HSG to assist the radiologist if needed. Many gynecologists will do the HSG themselves.

The major risk of an HSG is that of spreading an unrecognized infection from the cervix up into the tubes. This is uncommon, but in order to reduce the risk, many doctors advise antibiotic coverage during the procedure.

If the HSG shows that the tubes are closed, then it may be advisable to repeat the HSG; and also to do a laparoscopy to confirm this diagnosis.

Laparoscopy. This has already been described, and is the gold standard for making a diagnosis of tubal disease.

Limitations of HSG and laparoscopy

The trouble with both HSG and laparoscopy is that they only provide information as to whether or not the tube is open or closed. While a closed tube will never work, they do not provide any information on how well an apparently open tube works. Remember that just because a tube is patent does not necessarily mean that it works!

Another limitation is that they will rarely provide any information as to why the tubes are blocked. Occasionally, however, this can be suspected by other signs (for example, by seeing the tubercles diagnostic of TB in the abdomen during laparoscopy).

Recent innovations in the field:

Fluoroscopic guided procedures: Using an image intensifier, and techniques borrowed from coronary angioplasty, radiologists can now insert special catheters under fluoroscopic guidance into each of the tubes. This is called selective salpingography; and allows much better visualization of each tube. It also allows the radiologist to treat cornual blocks that are due to mucus plugs, by tubal cannulation.

Sonosalpingography: Under ultrasound guidance, with Doppler facilities, if available, the gynecologist can inject fluid into the tubes through the cervix and see the flow of the fluid into the tubes and abdomen on the ultrasound screen. This is a simple bedside test that a gynecologist can do to judge if the tubes are normal and can be reassuring if positive.

Tuboscopy: At the time of laparoscopy, the doctor can insert a fine telescope into the fallopian tube through its fimbrial end to inspect the inner lining of the tube to judge whether or not it is healthy.

Falloposcopy is a recent advance, the pioneered by Dr Kerin of USA. In this method, a very fine flexible fiber optic tube is guided through the cervix and uterus into each fallopian tube, thus allowing the doctor to actually visualize the inner lining of the entire length of the fallopian tube - something that was never possible so far. This can provide useful information about the extent of tubal damage - and the possibility for successful repair.

Surgical Treatment

Once the doctor has assessed the damage and pinpointed the location of the blockages he will decide on treatment alternatives and how to proceed. The first choice in the past used to be an attempt at surgery to repair the tubal damage. However, because results with tubal surgery were not very encouraging, many patients with tubal damage are now advised to undergo IVF (in vitro fertilization) as their first treatment option.

In order to select between IVF and tubal surgery, we need to differentiate between intrinsic tubal damage and peritubal damage. If the tubes have been damaged because of a problem outside the fallopian tubes, such as peritubal adhesions or endometriosis, which have caused the tubes to get kinked, then surgery may be useful. However, surgery is not advisable for patients if the tubes have been blocked because of TB; the tubes are very badly damaged; if the tubes are blocked at multiple places; or if the tubes have been blocked because of intrinsic tubal disease.

The likelihood of surgical success (in terms of pregnancy) depends on the severity of the tubal damage. If a previous infectious process has caused scarring of the fallopian tube, the inner delicate lining may have become irreversibly damaged. Surgery can result in re-establishing patency in some cases but the main aim of the surgery is not to just open the tubes, but to achieve pregnancy - and the tubes have to become capable of capturing the egg and transporting it to the uterus for this to happen. Unfortunately, surgery cannot reverse tubal damage once this has occurred.

What if only one tube is blocked? One normal tube is sufficient to allow a pregnancy and most surgeons would not advise tubal surgery for these patients. Obviously, the chance of pregnancy for such patients is half that of normal women and therefore establishing a pregnancy may take twice as long. The danger of trying to surgically repair a single blocked tube is that adhesions because of the surgery may cause both the tubes to become blocked!

Tubal Microsurgery

Microsurgery entails the use of the following surgical techniques:

Using a microscope (for adequate magnification)
Avoiding unnecessary trauma to the tissues
Employing delicate surgical instruments
Employing fine suture (stitching) material and ensuring precise suturing
Handling tissues with great care and respect, to minimize tissue damage
Ensuring that no bleeding is left unattended and no clots are left behind (because this can lead to the formation of adhesions or scar tissue after the surgery).
The microsurgery operation may take from 1 to 4 hours. Depending on the extent of pelvic damage it is usually done under spinal or general anesthesia. The incision used is usually a "bikini cut" (Pfannensteil incision). The length of stay in hospital is usually three to seven days. Tubal microsurgery can be expensive and may cost up to Rs.40,000. Sometimes a "check or second-look laparoscopy " is performed about one week after surgery to ensure that tubal patency is maintained and to remove any small adhesions that may have started to re-form.

Proximal Tubal Damage

The tubal obstruction could be at the uterotubal junction and this is called a cornual block. The conventional surgical repair of cornual blocks involved reimplanting the tube into the uterus and had dismal success rates. However, with microsurgery, it is possible to see the very fine ends of the tubes under high magnification and to join them together. This has a pregnancy rate of about 50%, since the function of the rest of the tube is basically intact.

Recently, doctors have realized that a number of patients have cornual blocks because of the presence of mucus plugs and debris in the very fine cornual segment of the tubes. Newer non-surgical methods have now been devised to treat this. These involve the passage of a fine guide wire or a fine balloon into the cornual end of the tube through the uterus. This is called a "balloon tuboplasty" or "cornual recanalisation," and can be done under ultrasound guidance; hysteroscopic guidance, or fluoroscopic (X-ray) guidance. This is a significant advance, since it saves patients the need for major surgery, and also has excellent pregnancy rates.

Salpingolysis

This procedure entails division of adhesions surrounding the tubes. When no other damage is apparent, success rates may be as high as 65%.

Tubal Reanastomosis

These include a variety of procedures that involve removing the damaged portion of the tubes and rejoining the healthy ends of the tube together. Success rates vary according to the area of damage but are usually within the range of 20 - 50 percent. The chances of success are higher when the defect occurs in the middle section of the tube.

Distal Tubal Damage

If the tubes have been severely damaged and have formed a hydrosalpinx (in which the fimbriae stick to one another and the tube is closed off) the surgery required is called neosalpingostomy, in which the surgeon opens the hydrosalpinx and creates a new opening for the repaired tube. While this is technically easy, success rates are very poor (about 20%) because the physiologic functioning of the fimbriae rarely returns to normal.

If the damage is less severe (fimbrial agglutination, in which the fimbriae are stuck to one another; or phimosis, in which the tube is narrowed, but open), then surgical repair is more successful, with pregnancy rates being about 50%.

The risk of having an ectopic (tubal) pregnancy is increased following tubal surgery. Fallopian tubes that have been operated on may have a damaged inner lining, and this can impair the movement of the embryo down the tube. This is why, in patients who have had tubal surgery, the diagnosis of a pregnancy should be made as soon as possible (preferably within a few days of missing a menstrual period), to rule out the possibility of an ectopic pregnancy.

The best chance of success is with the first surgical operation; therefore, you need to go to a specialized center. The chances of success will depend upon the extent of tubal damage and also on the skill of the surgeon. The best chance of achieving a pregnancy is in the first few months after surgery, and most women who are going to get pregnant after tubal surgery will conceive within this time. Some doctors believe that using ovulation induction and / or intrauterine insemination after tubal surgery helps to maximize the chances of a pregnancy.

If the patient has not conceived within one year after the surgery, then follow-up testing in the form of an HSG and / or laparoscopy is advisable, to determine whether the fallopian tubes are still open.

If the first surgery has been unsuccessful, the chance of success as a result of a second operation is very low, and IVF is the only treatment choice for such patients.

In the future, it is possible that tubal transplants may become a reality and that scientists may also develop artificial synthetic tubes to replace damaged ones.

With operative laparoscopy, it is now possible to open damaged tubes through the laparoscope, thus saving the patient major surgery. A hydrosalpinx can be repaired by opening it with a laser or cautery and then keeping it open with sutures: and even the complicated operation of tubal reanastomosis has been performed by experienced surgeons through the laparoscope (using sutures or special adhensive glue). Advances in operative laparoscopy may soon make conventional tubal microsurgery obsolete.

Reversal of Sterilization

In women, sterilization for family planning is usually done through an operation called tubal ligation, which is usually carried out through the laparoscope. The aim of the operation is to block the tubes and prevent the sperm and egg from meeting each other.

Why Do Women Ask for Reversal?

The vast majority of people are very happy with sterilization. Nevertheless, there are a few women who are very distressed afterwards and would do almost anything to get things undone. The commonest reason why such women regret sterilization is because their child dies or because they have remarried and wish to bear their new husband's child.

What Can Be Done?

If there is a reasonable amount of tube remaining, even if only on one side, then it may be possible to perform tubal microsurgery to rejoin the tubes. On the whole, the more the tube which has been left undamaged, the better the chances of success. Thus, patients who have had a tubal ligation done through the laparoscope, using Falope rings (silastic bands) or clips, have an excellent chance of achieving a pregnancy after microsurgical reversal of the ligation, because these methods cause minimal tubal damage.

After reviewing the operative notes, a laparoscopy may be advised so that the exact state of the fallopian tubes can be assessed. If the patient has enough normal tube, tubal microsurgery may be attempted and pregnancy rates can be as high as 75% in favorable cases. If, unfortunately, the patient has had both tubes completely removed or if the tubes are very badly damaged, then the only chance of success will be with IVF

Credits: Dr. Aniruddha Malpani, MD and DR. Anjali Malpani,