Ectopic pregnancy

In this film, Arnold Swarznegger gets pregnant through an inventive mix of fertility drug, progesterone and creative license. Whilst very, very unlikely, it is technically possible, despite how bad his acting is.

Definition

Where an embryo implants outside of the uterus.

Epidemiology

It is becoming more common in the UK, around 1 in 100 pregnancies. It is one of the leading causes of maternal mortality.

Pathophysiology

The fertilised embryo usually implants in the uterine cavity, but can actually implant anywhere. 95% of the ectopic prgnancies implant in the uterine tubes, but they can also implant in the cervix, the ovary and in the abdominal cavity.

The problem is that these areas are not designed to support growth, and cannot deal with the blood supply needs, nor the capacity for expansion that a growing baby requires. OFten an ectopic pregnancy will spontaneously abort, leading to a miscarriage.

Otherwise, if not dealt with, it can lead to rupture of the placenta, where it falls off the inappropriate site, leading to massive bleeding, or rupture of the anatomical structure to which it is attached. This can cause huge amounts of pain and bleeding, and lead to death of the foetus, and sometimes, the mother.

Risk Factors

• Smoking
• PID
• Advanced maternal age

Clinical Features

Tend to present as one of the following:

1. Most commonly, the woman presents as a normal pregnancy, with perhaps some abdominal pain, often one sided, occasionally with some referred pain, or irregular vaginal bleeding.
2. Next most common is emergency, where a woman collapses and is taken to hospital. A pregnancy test is done, and se is found, in theatre, to have a ruptured ectopic with bleeding into the abdomen
3. Finally, patients who are known to be at risk of ectopic are detected through routine early screening.

Investigations

• First up is pregnancy test. If this is negative, its almost guaranteed not to be an ectopic.
• After about a month, ultrasound can show if there is a foetus in the womb. If it is in the womb, then ectopic is excluded, otherwise, if pregnancy is confirmed, but the presence of the embryo is confirmed outside of the uterus, then you have an ectopic pregnancy.

Management

A large percentage of these sort themselves out - about half. Monitor the mum, and she will miscarry and the problem is over.

Sometimes, though medical intervention may be needed. The first line treatment is methotrexate which is an antimetabolite, which stops the cells dividing, and in effect kills the foetus.

If this doesn't work, then surgical removal, through laparoscopy, of the foetus may be neccesary. In several cases, removal of the uterine tube is also necessary; salpingectomy.