The fallopian tubes are paired tubular organs connecting the peritoneal cavity towards the ovaries and endometrial cavity in the uterus. The tubes are divided into four parts: the intramural portion (from the endometrial cavity to the uterine cornua), the isthmus, the ampulla, and the infundibulum (the funnel-shaped opening into the peritoneal cavity). They are also lined with hair-like structures, named fimbria, which contribute to egg travel from the ovaries down to the uterus and stimulate sperm to move. Any blockage of the fallopian tubes can cause infertility by preventing the embryo from reaching the uterus and sperm from moving towards the oocyte.
Symptoms
Most frequently, the tubal blockage isn’t presented by any symptoms, except difficulties in conceiving, when the couple has no success after more than one year of trying. However, in some situations, women may experience pain in the pelvic region or abdomen. Sometimes, a blockage in a fallopian tube can cause a fertilized egg to get stuck, which is known as an ectopic pregnancy[1]. This condition is dangerous and requires immediate medical help.
Causes
The reasons for the blockage may vary and include:
- the history of pelvic inflammatory disease, caused by sexually transmitted infections, such as gonorrhea, chlamydia, etc[2]
- the history of abdominal surgery
- history of ruptured appendicitis
- endometriosis (the condition when the inner lining of the uterus grows outside the uterus)
- tubal ostial polyps[3]
- cornual polyps
All these conditions may cause adhesions, tubal blockage, injury of mucosa or muscles, resulting in tubal dysfunction.
The other possible cause for the tubal disease is salpingitis isthmica nodosa, characterized by outpouching of the epithelium in the isthmus of the fallopian tube and hypertrophy of smooth muscles. This condition is highly associated with ectopic pregnancy[4].
When the blockage is situated at a few points, it may tend to hydrosalpinx, the swelling of the fallopian tube when itʼs blocked with watery fluid. It happens if the secretions of tubal mucosa have a mechanical preventing of drainage into the peritoneal or uterine cavities.
Impact on female fertility
When a woman is healthy, around the 14th day of the menstrual cycle, an egg is released from an ovary and starts to travel down. For a woman to become pregnant, her egg must meet with sperm. And if the fallopian tubes are blocked, it can not happen.
Sometimes, only one tube can be blocked. In months, when the egg is released from the other side or both, a pregnancy can occur. But it doesn’t mean that tubal blockage will have no impact on pregnancy outcome. According to recent research, tubal occlusion may impair blood flow to the uterus and ovaries and affect implantation and oocyte quality[5]. Moreover, a damaged fallopian tube can leak fluid into the uterus during pregnancy.
Diagnosis
Fallopian tubes are not always in open condition. That’s why it can be challenging to detect their blockage. The methods that can be used include hysterosalpingogram, or HSG (X-ray test), sonohysterogram (ultrasound test), and laparoscopy.
A laparoscopy is the most accurate test for fallopian tubes diagnostics. But doctors do not always recommend it because of its invasiveness.
Surgery techniques
The main goals of tubal blockage surgery are to remove pathology, restore normal anatomy and reverse functioning. The main surgery principles are using atraumatic instrumentation, micro suturing, irrigation to prevent desiccation, and hemostasis support.
For repairing the blockage, a procedure called fallopian tube cannulation should be provided. It doesn’t require any cuts. The small tube will be inserted through the vagina into the uterus, and with the help of X-ray and contrast, fallopian tubes can be seen, and the blockage revealed. Then a small catheter will be inserted to clean the obstruction.
However, depending on the topology and severeness of damage, the chosen surgery technique has its own specifics[6].
Intramural obstruction
This surgery type involves resection of cornual polyps and tubal reimplantation. The tubal patency is restored using hysteroscopy by visualizing tubal ostia in the endometrial cavity and inserting a tiny wire with a small catheter inside it. If dye through the catheter in the intramural part of the tube can be visualized through the fimbria, a surgeon can confirm the patency.
Isthmic occlusion
If a woman had her fallopian tubes cut or blocked to prevent pregnancy, she could undo the procedure with tubal ligation reversal surgery. Doctors may perform anastomosis to repair this type of damage. The occluded part is resected, initially proximally and subsequently distally. The patency must be confirmed in both proximal and distal portions. Then the tube will be reconnected.
Distal occlusion
Repairing this tubal part usually requires fimbrioplasty (salpingostomy). It is the operation when a doctor creates an opening in the fallopian tube. Before the procedure, the proximal patency should be checked. The entrance of the tube must be opened using scissors, diathermy, or laser. Then fimbria must be retracted, using sutures or thermal damage to the peritoneal surface of the fallopian tube.
Surgery outcome
The probability of conceiving after surgery is affected by a woman’s age and level of fallopian tube damage. Recent studies reported that 27%, 47%, and 53% of women with proximal tubal blockage achieved a pregnancy within 1, 2, and 3.5 years after surgery, respectively. For reversal of sterilization, pregnancy rates should be around 80% in the first years, depending on the age[7].
References
- Ectopic pregnancy. 2016. National health service (UK).
- Jennings LK, Krywko DM. Pelvic Inflammatory Disease. 2021 May 13. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–. PMID: 29763134.
- Lee A, Ying YK, Novy MJ. Hysteroscopy, hysterosalpingography and tubal ostial polyps in infertility patients. J Reprod Med. 1997 Jun;42(6):337-41. PMID: 9219120.
- Bolaji II, Oktaba M, Mohee K, Sze KY. An odyssey through salpingitis isthmica nodosa. Eur J Obstet Gynecol Reprod Biol. 2015 Jan;184:73-9. doi: 10.1016/j.ejogrb.2014.11.014.
- Akmal El-Mazny, Wafaa Ramadan, Ahmed Kamel, Sherine Gad-Allah. Effect of hydrosalpinx on uterine and ovarian hemodynamics in women with tubal factor infertility. European Journal of Obstetrics & Gynecology and Reproductive Biology. Volume 199. 2016. Pages 55-59. ISSN 0301-2115. doi: 10.1016/j.ejogrb.2016.01.046.
- Ahmad G, Watson AJ, Metwally M. Laparoscopy or laparotomy for distal tubal surgery? A meta-analysis. Hum Fertil (Camb). 2007 Mar;10(1):43-7. doi: 10.1080/14647270600977820.
- Boeckx W, Gordts S, Buysse K, Brosens I. Reversibility after female sterilization. BrJObstetGynaecol.1986Aug;93(8):839-42.doi: 10.1111/j.1471-0528.1986.tb07992.x.