Surgical therapy is one of the possible ways to treat ectopic pregnancy, i. e. a pregnancy where the embryo implants outside the uterine cavity.
About ectopic pregnancy
An ectopic pregnancy is a complication of pregnancy in which the embryo implants outside the uterine cavity (Pic. 1). About 1% of pregnancies are in an ectopic location. 98% of ectopic pregnancies are tubal, which means that the implantation occurs in the Fallopian tubes. Besides the Fallopian tubes, an embryo can also implant in the cervix, ovaries, and abdomen (Pic. 2).
In a tubal ectopic pregnancy, the embryo adheres o the lining of the Fallopian tube and burrows into the tubal lining. Most commonly, this invades vessels and will cause hemosalpinx (i. e. bleeding into the Fallopian tube; Pic. 3). Since internal haemorrhage is a life-threatening complication, an ectopic pregnancy is a potential medical emergency, and, if not treated properly, can lead to death of the mother. Fetuses usually do not survive an ectopic pregnancy.
Besides the “classical” tubal pregnancy, a chronic ectopic pregnancy can also occur. In such a pregnancy, minor ruptures or abortions occur instead of one episode of bleeding. This leads to an inflammation often leading to formation of a pelvic mass. Diagnosis of a chronic ectopic pregnancy is usually difficult. So is surgical treatment, since normal anatomy is distorted by chronic inflammatory changes and adhesions.
Surgical therapy of ectopic pregnancy
Surgical intervention is required in cases were the Fallopian tube has ruptured or is in danger of doing so (Pic. 4). The intervention can be laparoscopic (i. e. using a camera and tools inserted into the body through small incisions) or through a larger incision, known as a laparotomy (a classical, open surgery). It is either possible to incise the affected Fallopian tube and remove only the pregnancy (this is known as salpingostomy or salpingotomy), or to remove the affected tube with the pregnancy (salpingectomy).
If the patient desires to retain her reproductive potential, tube-preserving surgery can be performed. This, besides salpingotomy, includes salpingostomy, segmental tube resection and reanastomosis (removal of the pregnancy and surrounding tubal tissue, and subsequent connection of the free ends) and fimbrial milking (i. e. gently pushing the pregnancy out of the Fallopian tube).
When the embryo has implanted in the tubal isthmus (i. e. the narrowest portion of the Fallopian tube), it quickly invades the muscular layer. The optimal treatment choice is thought to be segmental tubal resection and reanastomosis (i. e. surgically removing a part of the Fallopian tube and reconnecting the residues). This is because, with salpingotomy, embryonic tissue residues are more likely to occur, which requires additional rescue therapy. However, segmental tubal resection with reanastomosis is time-consuming and requires expertise and great microsurgical experience.
Generally said, proper and early diagnosis decreases the intra- and postoperative complications. In cases of rupture, a massive internal bleeding can occur, which can be life-threatening to the patient.
Good control of bleeding is fundamental, especially in tube-preserving surgeries. If bleeding persists, salpingectomy should be performed instead.
Another important ascpect is facilities and experience of the hospital department. In developed countries, proper management with a use of blood transfusions, infusions, optimal techniques to handle bleeding, constant counselling and proper follow up of the patients leads to successes in treatment.
In surgical treatment of heterotopic pregnancy (i. e. simultaneous presence of intrauterine and extrauterine pregnancy), the optimal management remains controversial.
In surgery in general, possible complications include inflammation of the wound, bleeding, or excessive pain. Moreover, a hospital acquired inflammation can develop, for example pneumonia (i. e. inflammation of the lungs) or urinary tract infection.
When treating a heterotopic pregnancy, abortion of a remaining fetus can occur.
When surgically treating an ectopic pregnancy, the prognosis for the fetus is clearly unfavourable. On the other hand, prognosis for the mother is very good.
In treatment a heterotopic pregnancy through salpingostomy, a 40% of viable foetuses have reported. Many cases have confirmed the safety of laparoscopy.
As for future fertility, the way of treating an ectopic pregnancy does not play a major role; the rates of intrauterine pregnancy 2 years after treatment of ectopic pregnancy are approximately 64% with radical surgery, 67% with medication, and 70% with conservative surgery. In comparison, the cumulative pregnancy rate of women under 40 years of age in the general population over 2 years is over 90%.
Genarally said, the patient’s Fallopian tubes are affected. This leads to a decrease in fertility. Future fertility in these patients depends on several factors, the most important of which is a prior history of infertility. Other factors include age, history of previous ectopic pregnancies, tubal rupture, and contralateral tubal lesion.
A history of a tubal pregnancy increases the risk of future occurencies to about 10%. This risk is not reduced by removing the affected tube, even if the other tube appears normal. The best method for diagnosing this is to do an early ultrasound.