Ectopic Pregnancy

Ectopic Pregnancy

An ectopic pregnancy occurs when a fertilised ovum implants outside of the uterus. The most common location is one of the fallopian tubes due to tubal dysfunction.

In the UK, there are approximately 11,000 ectopic pregnancies annually and the incidence is increasing.

Aetiology

Ectopic pregnancies are classified by the anatomical site of implantation of the pregnancy:

• Tubal (usually ampulla): 93%
• Interstitial (implantation in the interstitium where the fallopian tube meets the uterus): 1.1 -6.3%
• Cervical: 0.15%
• Ovarian: 0.5%

Ectopics can occur in the myometrium when a fertilised ovum implants in a Caesarean section scar. There have been isolated cases of ectopic pregnancies as far afield as the liver.

Risk Factors

There is often no identifiable cause for ectopic pregnancy. However, the following risk factors are associated with an increased likelihood of developing the condition:

• Previous ectopic pregnancy (indicating damage to a fallopian tube)
• Assisted reproduction techniques (e.g. in-vitro fertilisation)
• History of pelvic inflammatory disease (resulting in tubal occlusion due to adhesions)
• Endometriosis
• Tubal occlusion from sterilisation*
• Intrauterine contraception*

*Sterilisation and intrauterine contraception considerably decrease the chance of pregnancy. However, if pregnancy occurs, the risk of ectopic pregnancy is increased.

Clinical Features

Patients with an ectopic pregnancy usually present with unilateral abdominal pain from 5 weeks of expected gestation onwards. Patients may be unaware of the pregnancy and using contraception.

In some cases, patients may present significantly shocked due to haemorrhage following the rupture of the ectopic pregnancy.

History

Typical symptoms of ectopic pregnancy include:

• Abdominal pain (usually unilateral but can be bilateral)
• Pelvic pain
• Amenorrhoea or a missed period
• Vaginal bleeding (with or without clots)
• Dizziness, fainting or syncope
• Shoulder tip pain

Other important areas to cover in the history include menstrual history, sexual history, past medical history, and medication history.

Clinical Examination

In the context of a suspected ectopic pregnancy, a pelvic examination is necessary.

Typical clinical findings in ectopic pregnancy include:

• Pelvic or abdominal tenderness
• Adnexal tenderness
• Vaginal bleeding
• Haemodynamic compromise: if rupture and haemorrhage

Pregnancy Testing

Any woman of reproductive potential who presents with abdominal or pelvic pain should always have a pregnancy test.

Investigations

Bedside investigations

Relevant bedside investigations in the context of ectopic pregnancy include:

• Basic observations (vital signs): to assess for haemodynamic compromise
• Urine pregnancy test (hCG urine dipstick): would be positive in ectopic pregnancy.
• Urinalysis: to exclude a urinary tract infection. If findings suggest a urinary tract infection, ectopic pregnancy would still need excluding (as the patient may have both).
• Vaginal swabs: to assess for sexually transmitted infections (which can pre-dispose to an ectopic pregnancy)

Laboratory investigations

Relevant laboratory investigations in the context of ectopic pregnancy include:

• Baseline blood tests (FBC, U&E, coagulation, CRP): white cells may be raised, and there may be anaemia
• Serum hCG: the level will depend on the gestation and viability of the pregnancy. This is often used to monitor response to treatment (see below)
• Group and save: important to perform as the patient may require a blood transfusion

Imaging

Relevant imaging investigations in the context of ectopic pregnancy include:

• Transvaginal ultrasound scan: the most accurate method of confirming the presence of tubal ectopic pregnancy

Management

Initial assessment

An assessment of the patient should be undertaken if the pregnancy test is positive, as they may have an ectopic pregnancy until proven otherwise.

Ectopic Pregnancy - ABCDE Approach and Definitive Management

The ABCDE approach should be followed during the initial assessment and management of patients with suspected ectopic pregnancy. Ectopic pregnancy may present with significant haemodynamic instability requiring resuscitation and blood transfusion.

Definitive Management

There are three management options for ectopic pregnancy, depending on the haemodynamic stability of the patient and investigation findings:

• Expectant management
• Medical management
• Surgical management

If the ectopic pregnancy has ruptured, surgical management is usually required. The decision between expectant and medical management, and medical and surgical management, depends on NICE guidelines and patient preference.

Expectant Management

Expectant management includes monitoring serum bHCG and performing serial ultrasound scans to monitor the ectopic pregnancy until it spontaneously resolves (‘watch and wait’ approach). Expectant management is suitable for women who meet the following criteria:

• Pain-free
• Haemodynamically stable
• Tubal ectopic pregnancy visible on ultrasound measuring <35 mm (and no visible heartbeat)
• Serum hCG <1,000 IU/L*
• Able to return for follow-up

Expectant management can also be considered for women who have a serum hCG between 1,000 -1,500 IU/L, providing they meet the other criteria.

Medical Management

Medical management involves using methotrexate to stop the growth of the ectopic pregnancy and allow resolution to occur. Medical management is suitable for women who meet the following criteria:

• No significant pain
• Unruptured ectopic pregnancy with an adnexal mass <35 mm (and no visible heartbeat)
• No intrauterine pregnancy is seen on the ultrasound scan: some women may have a heterotopic pregnancy where an intrauterine pregnancy occurs alongside an ectopic pregnancy
• Serum hCG <1500 IU/L*
• Able to return for follow-up

*Women with a serum hCG between 1500 -5000 may be considered for medical management. The serum hCG level is monitored to ensure it is declining and not continuing to rise. If serum hCG levels continue to rise, a re-assessment of the management plan should occur.

Surgical Management

Surgical management involves the surgical removal of the ectopic pregnancy. Surgery should be offered to those women who meet any of the following criteria:

• Unable to return for follow-up
• Significant pain
• Adnexal mass ≥35 mm
• Fetal heartbeat visible on the scan
• Serum hCG level ≥5000 IU/L

In cases of tubal ectopics, a laparoscopic salpingectomy is usually performed, removing both the ectopic pregnancy and the fallopian tube. Anti-D prophylaxis should be given to all rhesus-negative women who undergo surgical management of an ectopic pregnancy.

Surgical Management Options

Salpingectomy is the removal of the ectopic pregnancy along with the fallopian tube. It is the preferred option in women with no other risks to their fertility, as it reduces the likelihood of a repeat ectopic pregnancy. It can affect future fertility, so women should be carefully counselled about the pros and cons of the procedure.

Salpingotomy is an alternative that seeks to remove the ectopic pregnancy whilst preserving the fallopian tube. It is usually offered to women with other fertility issues, such as damage to the other fallopian tube. It does carry a greater risk of a future ectopic pregnancy than a salpingectomy.

Complications

If an ectopic pregnancy is not diagnosed and treated promptly, potential complications can include fallopian tube or uterine rupture, secondary massive haemorrhage and death.

Complications of surgical management can include: bleeding, infection and damage to local structures (uterus, bladder, bowel, vasculature).

Psychological Support

Whilst an ectopic pregnancy is a potentially life-threatening situation for a woman, it is also important to acknowledge the removal of an ectopic pregnancy as the loss of a much-longed-for pregnancy. Therefore, emotional support should be offered to the woman in the same way as anyone who has experienced early pregnancy loss.

Women who have undergone a salpingectomy may need additional emotional support to come to terms with the potential future fertility impact.

The Ectopic Pregnancy Trust website offers useful resources for patients and professionals.

Key Points

• An ectopic pregnancy occurs outside of the uterus.
• The most common ectopic pregnancy location is in one of the fallopian tubes.
• Typical symptoms include abdominal pain, pelvic pain, amenorrhoea and vaginal bleeding.
• Clinical findings may include pelvic or abdominal tenderness and adnexal tenderness.
• Diagnosis requires urine hCG, serum hCG and abdominal ultrasound.
• Medical management involves the administration of systemic methotrexate.
• Surgical management involves removing the ectopic pregnancy.
• Complications can include fallopian tube rupture, haemorrhage and death.