Worst outcomes if missed
- Death – according to the latest report from the Confidential Enquiry into Maternal and Child Health – now known as the Centre for Maternal and Child Enquiries – there has been a decline in the case fatality rate from ectopic pregnancy from 31.2/100000 in the 2003-2005 period to 16.9/100000 in 2006-2008. This has largely been due to more sensitive urine pregnancy kits and easier access to transvaginal scans. But the report states improvements could still be made as substandard aspects of care were identified in most of these cases.
- Morbidity – intra-abdominal bleeding, shock, disseminated intravascular coagulopathy and impact on future fertility.
Epidemiology
An ectopic pregnancy occurs in 1 in 100 pregnancies.
Risk factors include:
- previous ectopic pregnancy
- previous pelvic inflammatory disease
- previous tubal surgery including tubal ligation or reversal
- infertility secondary to tubal disease
- intrauterine contraceptive device in situ
- assisted conception techniques
- smoking
However, risk factors are not present in a third of patients with an ectopic pregnancy.
Symptoms and signs
The classic triad of ectopic pregnancy occurs in less than 50% of patients and includes:
- amenorrhoea, typically of 5-8 weeks
- abdominal pain, often unilateral
- vaginal bleeding, usually light
Early symptoms may be absent or nonspecific - mimicking other abdominal pathologies. These include:
- nausea
- vomiting
- diarrhoea
- pain on micturition or defecation
Late symptoms associated with ectopic pregnancy rupture and haemoperitoneum include:
- shoulder tip pain
- fainting
- severe abdominal or back pain
Signs include:
- hypovolaemic shock – tachycardia, low systolic blood pressure, cold and sweaty skin, pallor
- abdominal examination – direct or rebound tenderness, rigidity, guarding
- vaginal examination (to be avoided in primary care due to small risk of rupture of ectopic mass) – cervical excitation, adnexal tenderness and/or fullness
Differential diagnoses
- early normal intrauterine pregnancy
- threatened miscarriage
- ovarian accident (torsion/cyst rupture)
- gastroenteritis
- appendicitis
- urinary tract infection
Investigations and referrals
- Perform a urine pregnancy test on all women in the reproductive age group presenting with abdominal pain. Current urine hCG kits are very sensitive and can detect a positive result as early as three to four days post-embryo implantation with hCG levels above 25 IU/l. 98% will be positive by seven days post-embryo implantation or about the time of the missed period.
- All women with early pregnancy complications presenting with pain and/or bleeding should be referred to an early pregnancy assessment unit.
- Immediate referral to an early pregnancy assessment unit or acute gynaecological service for further assessment and investigations if a patient has any late symptoms. In the hospital setting, the following will be arranged:
o Transvaginal scan (if haemodynamically stable) to identify the location of the pregnancy
o FBC, group and save – cross match if haemodynamically unstable
o Serum hCG:
- hCG doubles every 36-48 hours in normally growing intra-uterine pregnancies but in only 15% of ectopic pregnancies. A suboptimal rise is highly suggestive of an ectopic pregnancy.
- Very early pregnancy is not reliably detected by transvaginal ultrasound if serum hCG level is less than 1500 IU/L.
- If serum hCG is over 1500 IU/L and an intrauterine pregnancy is not identified on transvaginal scan, an ectopic pregnancy should be suspected. In the absence of an adnexal mass suggestive of an ectopic pregnancy, a diagnosis of pregnancy of unknown location is made. Clinically stable patients should be followed up with serial hCG measurement every 48 hours to help with the management.
- Serum progesterone should not be used as an adjunct to differentiate between ectopic pregnancy and early intrauterine pregnancy when early ultrasound scan suggests a pregnancy of unknown location.
Management
Management of ectopic pregnancy must be based on the patient’s clinical condition, future fertility requirements and the facilities and expertise of the available staff.
Haemodynamically unstable patient:
- Assess for signs of haemodynamic shock – pulse over 100, systolic blood pressure below 90 mmHg, peritonism.
- Immediate transfer by ambulance to the nearest accident and emergency or early pregnancy assessment unit for resuscitation and urgent surgical management.
Haemodynamically stable patients:
- Expectant management is offered to women with a pregnancy of less than six weeks who are bleeding but not in pain. Women are advised to repeat the pregnancy test in 7-10 days and return if it remains positive or to return if their symptoms continue or worsen.
- Expectant or medical management should only be offered by units which are able to offer women 24-hour telephone advice and emergency admission if required. Patient’s eligibility to receive either treatment is based on strict criteria. Moreover, patients should be willing to comply with close surveillance.
- Surgical management:
o Salpingectomy versus salpingostomy to be determined based on the patient’s history, fertility plans, status of the contralateral tube
o Laparoscopic management is the standard surgical approach.
Key questions
1. Does the patient have any of the risk factors of ectopic pregnancy?
2. Are patients with a previous ectopic pregnancy aware of their increased risk of having ectopic pregnancy and the importance of an early scan in subsequent pregnancies?
3. Have you performed a urine pregnancy test prior to referring patients in with abdominal pain for review?
4. Have patients with a pregnancy of unknown location received written information about what to do if they develop any new or worsening symptoms?
5. Has anti D been given to all nonsensitised rhesus negative patients following treatment for an ectopic?
Four red herrings
- The symptoms and signs of ectopic pregnancy can resemble the common symptoms and signs of other conditions. Consider offering a pregnancy test to women of reproductive age even when symptoms are non-specific.
- Beware that in otherwise fit young women symptoms of hypovolaemic shock occur very late, by which point they are very unwell.
- Exclude the possibility of ectopic pregnancy, even in the absence of risk factors such as previous ectopic pregnancy, because about a third of women with an ectopic pregnancy will have no known risk factors.
- An ectopic pregnancy needs to be ruled out if an intrauterine sac can not be identified on early pregnancy scan. Follow-up is required according to the local early pregnancy unit protocol.
- 30% of ectopic pregnancies present before a period has been missed.
Miss Leila Fahel is a senior registrar in obstetrics and gynaecology at Bradford Teaching Hospitals NHS Trust. Professor Sian Jones is a consultant in obstetrics and gynaecology at Bradford Teaching Hospitals NHS Foundation Trust.
References
1 NICE. (2012) CG154: Ectopic pregnancy and miscarriage. London
2 Royal College of Obstetricians and Gynaecologists. (2006) The management of early pregnancy loss (Green-top 25). London
3 Haeri S, Ezzati M, Gomez-Lobo V et al. (2010) Ectopic pregnancy. Best Practice, London: BMJ Publishing Group Ltd
4 Map of Medicine. (2011) Clinical editorial team and independent reviewers invited by Map of Medicine. London
5 Joint Royal Colleges Ambulance Liaison Committee. (2006) Haemorrhage during pregnancy (including miscarriage and ectopic pregnancy). Obstetric and Gynaecological Emergencies, London
