If the fertilized ovum embeds outside the uterus the condition is known as an ectopic pregnancy. Most commonly this occurs in the ampulla portion of the fallopian tube. Other rare implantation sites are the abdomen, cervix, ovary and fallopian tube portions other than ampulla. The incidence of ectopic pregnancy is 1 in 150 conceptions.
Pelvic inflammatory disease as a result of early and indiscriminate sexual activity.
· Women who have had tubal surgery
· Women who have use the IUCD
The right and left fallopian tubes are involved with equal frequency, and rarely a tubes pregnancy may occur in both tubes.
Figure 19. Possible outcomes of a tubal pregnancy. (A) Tubal abortion. (B) Tubal mole. (C) Ruptured tubalpregnancy.
Implantation may occur in the fimbriated (17%); the ampulla (55%), the isthmus (25%) the interstitial portion (2%) and rarely the ovarian 0.5% or the abdominal cavity 0.1%. In most cases the pregnancy terminates between the 6th and 10th weeks of pregnancy.
The main cause is damage and distortion of the fallopian tubes. Implantation can occur at any point along the fallopian tube.
Secondary abdominal pregnancy
Manifests by mild lower abdominal discomfort with an occurrence of sharp acute attack of stabbing pain accompanied by nausea. This may be sufficiently severe for the mother to seek medical advice.
Usually there is a short period of amonrrhea in ruptured ectopic gestation fainting is usual Vaginal breeding may bemistaken for bleeding due to a delayed menstrual period or an abortion.
Slight brownish color and continuous breeding with rarely present crops.
This occurs in 65% of the cases and is the usual termination in fimbrial and ampullary implantation repeated small bleeding from the invaded area of the tubal wall separated the ovum., which dies and is either aborted completely or aborted thorough the tubal ostium into the peritoneal cavity or aborted incompletly so that the clot covered conceptus distends the ostium or forms a tubal blood mole
This occurs in 45% of cases, and is more common when the implantation is in the isthmus. If the implantation is in the isthmus, where the mucosa is thinner and the vessles are larger, penetration of the muscularity and tubal rupture occurs earlier and internal hemorrhage is usually sever, which if the implantation is in the interestial portion of the oviduct, rupture is often delayed as the myometrium surrounds the growing conceptus; but eventually it does occur and is attended by sever hemorrhage. The rupture is being sudden or gradual. Ifthe rupture is on the mesenteric side of the tube, a broad ligament haematoma will form.
Very rarely the extruded ovum continious to grow as sufficient trophoblast maintains its conception with the tubal epithelium and latter the trophoblast covering the ova sac attaches to abdominal organs. A few of these pregnancies advance to term and in a few fetus dies early.
Two clinical patterns occur, and are due to the extent of the damage to the tube wall by the invading trophoblast. The first is sub acute, the second acute.
After a short period of amenorrhea, the patient complains of:
· some lower abdominal discomfort, may be so mild
· occasionally there is an attack of sharp pain and faintness,
· an attack of sharp pain favored by slight breeding
· Tenderness of a lower abdomen on examination
· Vaginal examination show a tender fornix or a vague mass
· If the patient is observed, further episodes of pain will occur
· Vaginal bleeding, usually brown in color causing acute collapse indicating tubal rupture or incomplete tubalabortion or the symptoms could indicate complete abortion with or without pelvic haematocole.
Sudden collapse with little or no warning is more common when the implantation is isthamal, but is not the most frequent events. It is more usual for the acute tubal rupture to supervene upon the sub acute.
· The patient is seized with a sudden acute lower abdominal pain, sufficiently sever to case fainting
· The associated internal hemorrhage leaders to rapid contapse, with pallor a week pulse with a rising rate and a falling blood pressure usually the condition improves after a short time, as the hemorrhage diminishes or cases but abdominal discomfort persist and pain is felt in the epigastrium and referred to the shoulder.
· A further episode of hemorrhage and collapse is likely, and continued breeding can be suspected from increasing pallor and a falling hemoglobin level.
· On examination the patient is shocked, the lower abdomen is tender with some abdominal muscle guarding
· Vaginal examination, which should only be carried out in hospital, shows extreme tenderness in the fornixes and marked tenderness on movement from side to side.
· The presence of internal bleeding in acute cases. An immunological pregnancy test is positive in 75 % of cases which is not very specific if the BHCG test is positive, a pelvic ultrasound examination be made.
· If ultrasound examination shows fetus in the fallopian tube and empty uterus the diagnosis is certain and a laparotomy should be made If the diagnosis remains in doubt a laparoscopy will clear the matter up
When tubal pregnancy is suspected the patient must be transferred to hospital with out vaginal examination provided she is not in shock and intravenous infusion of saline or a plasma expander given.
As soon as the diagnosis of ectopic gestation is made in hospital, laparatomy should be performed at once, even if the patient is collapsed. Blood transfusion should be started as soon as after admission as possible.
Only 60 percent of patients who have had an ectopic gestation become pregnant again. Of the women who do not have a future pregnancy, 75 percent avoid pregnancy voluntarily, and 75 percent are involuntarily infertile. The riskof a second ectopic gestation is about 10 percent, as compared which 0.4 percent in other women. The chance of delivering a term baby is about 50 percent. Patients who have previously had an ectopic gestation therefore require additional care during pregnancy.