Ectopic Pregnancy - Pregnancy Which Occurs Outside The Uterus

 

Ectopic pregnancy

Ectopic pregnancy is defined as a pregnancy which occurs outside the uterine

cavity, the commonest site being the fallopian

tube. It may also occur, although  rare, in:

• ovary;

• cervix;

• abdominal cavity

Why Does Ectopic Pregnancy Occur

The ovum is fertilized in the fallopian tube and reaches the uterus in about five days. Anything that delays the passage of the fertilized ovum to the uterus can result in tubal pregnancy, such as

-intrauterine device (IUD) and progesterone-only pill (POP)

 Risk factors for ectopic pregnancy

Pelvic inflammatory disease (PID)

Previous pelvic surgery

Previous ectopic pregnancy

Intrauterine device (IUD)

Progesterone only pill (POP)

Depoprovera

Emergency contraception

Sterilization

Clinical features

The picture of ectopic pregnancy is:

Missed periods and a positive pregnncy test

Pain—typically constant and often unilateral due to spasm of the tubal muscle

Vaginal bleeding The bleeding is usually scanty, less than a normal period and dark brown in colour.

 Faintness or even shock with an acute rupture.

 How to Diagnose

Ultrasound is helpful. While it may not always show the embryo or its sac in the tube, findings may include:

• an empty uterus with thickened decidua;

• fluid (blood) in the pouch of Douglas;

• a multi-echo mass in the region of the tube.

Progesterone levels are commonly low because the pregnancy is failing.

Serum bhCG is usually lower than expected for gestation and on serial measurements increases by less than 60% over 48 hours.

 Laparoscopy is the ultimate investigation to make the diagnosis with direct vision

 

Differential diagnosis

The diagnosis is from any other acute abdominal conditions such as rupture of a viscus or acute peritonitis. The clinical picture is so typical that in most cases diagnosis presents no difficulty. Other diagnoses which may confuse are:

• inevitable miscarriage;

• bleeding with an ovarian cyst;

• pelvic appendicitis;

• acute salpingitis.

Treatment

The treatment of tubal pregnancy is removal of the pregnancy and sometimes the affected tube by laparoscopy or laparotomy. If the tube is patent and not seriously damaged, it may be possible to conserve it and thus leave the woman with a chance of conception later in life.

Laparoscopy techniques exist to:

• kill the embryo with a direct injection of methotrexate or mifepristone allowing absorption so requiring no surgery on the tube;

• incise the swollen tube over the ectopic pregnancy, aspirate the embryo, and achieve haemostasis (salpingostomy).

In a case of severe haemorrhage, the patient must be taken immediately to the operating theatre.

Little time should be wasted in attempting resuscitation which can prove useless and may only increase bleeding. 

An intravenous drip should be set up and a blood transfusion given as soon as possible.

In most cases the affected tube should be removed;

an exception may be made if the woman

desires children and the other tube is already missing

or seriously diseased. The disadvantage of conservation

is the increased risk of recurrence of

ectopic pregnancy.

 

• Medical treatment with methotrexate can be used if the hCG level is less than 5000 iu/l and the ectopic mass is less than 4 cm in diameter on ultrasound scan. There should be no symptoms or signs of rupture.