Management options in ectopic pregnancy
ctopic pregnancies are increasing with an estimated six-fold rise in industrialised countries over the past 20 years. Around 1 per cent of pregnancies in the UK are ectopic, accounting for more than four deaths a year. Although the fallopian tube is by far the commonest site for EP, they can develop in the cervix, ovary and peritoneal cavity. Heterotopic EP (tubal pregnancy with intrauterine pregnancy) is rare but occurs in up to 1 per cent of pregnancies conceiving after assisted reproduction.
EP is believed to be due to endothelial damage secondary to salpingitis but often there is no history of salpingitis and many women have no identifiable risk factors. A rising incidence of sexually transmitted infection, most notably chlamydial infection, is largely responsible for the increase; the incidence of EP increases seven-fold following one episode of salpingitis. Reducing the incidence of chlamydial infection is associated with a reduction in the incidence of ectopic pregnancy.
Pregnancy in the presence of an IUD, during use of a progesterone-only contraceptive or following tubal surgery (ligation, re-anastomosis) is often ectopic. Increasing age (>35) and a history of smoking are associated with a higher incidence. The incidence of ectopic pregnancy after in vitro fertilisation is 2-9 per cent, reflecting a high incidence of underlying tubal damage.
Presentation varies from haemodynamic collapse to symptom-free. A majority of women will describe non-specific lower abdominal discomfort with a variable amount of vaginal bleeding and amenorrhoea (see box on page 67). GPs are usually the first health professional to be consulted and should maintain a high index of suspicion of EP in the presence of these variable symptoms in a sexually active woman.
Performing a pelvic examination may elicit signs suggestive of EP (cervical excitation, adnexal swelling) but it will not establish the diagnosis which is more appropriately made in a hospital setting; vaginal examination carries an unquantifiable risk of provoking tubal rupture and intra-peritoneal haemorrhage. A negative urinary pregnancy test virtually excludes the possibility of EP and an alternative diagnosis should be sought (see box on page 67).
Until recently, diagnostic laparoscopy was the principal diagnostic tool with many negative procedures being performed out of hours. Today, transvaginal ultrasound (TVS) combined with quantifying serum human chorionic gonadotrophin (HCG) results in a more precise non-surgical diagnosis allowing most laparoscopies to be both diagnostic and therapeutic.
TVS will visualise an intrauterine pregnancy (IUP) from six weeks' amenorrhoea and this finding virtually excludes an EP unless the pregnancy is a consequence of assisted reproduction. Absence of an IUP and presence of an adnexal mass with or without peritoneal fluid is highly suggestive of an EP. Occasionally you can see a fetal pole with a heartbeat within the fallopian tube that is immediately diagnostic, but this is exceptional.
Difficulty might arise in differentiating an early miscarriage from an EP or a very early IUP from an EP. Serum HCG levels have been incorporated into departmental protocols to aid differentiation where both absolute levels of HCG and the trend over two or three days are measured to make a correct diagnosis easier.
For many years traditional management of EP was salpingectomy at the time of laparotomy through a low, transverse abdominal incision. In current gynaecological practice both surgical and non-surgical treatment options are available, each with their relative merits. Treatment will be influenced by the mode of presentation, size of EP, appearances of the contralateral fallopian tube, a patient's fertility status and the unit's resources and expertise.
Future fertility will be influenced by a number of factors including the woman's age and the appearance of the remaining fallopian tube. For the purposes of patient counselling it is appropriate to quote an overall subsequent pregnancy rate of 70 per cent with a recurrent EP rate of 10 per cent.
In general, laparoscopic treatment is associated with higher rates of IUP (77 per cent v 66 per cent) and lower rates of recurrent ectopic (7 per cent v 17 per cent) compared with laparotomy. Non-surgical treatment does not appear to improve subsequent pregnancy rates.
A woman's psychological reaction to an EP is unpredictable but it is important to recognise she has experienced a pregnancy loss as well as undergoing treatment for a potentially life-threatening condition. Additional information and support is available through the Ectopic Pregnancy Trust.
Maintaining a high index of suspicion of EP will enables GPs to make prompt referral for diagnosis and management. A majority of clinically suspected EPs are not confirmed following hospital investigation but vigilance and early referral can be expected to reduce short- and long-term morbidity.
Frequency of symptoms and signs in ectopic pregnancy
signs in ectopic pregnancy
· Abdominal pain >90%
· Vaginal bleeding 80%
· Tenderness on abdominal
· Adnexal tenderness on vaginal examination 50%
Differential diagnosis of EP
· Spontaneous miscarriage/
· Accident to ovarian cyst
· Pelvic inflammatory disease
Management options in ectopic pregnancy
Management options in ectopic pregnancy
Laparoscopic salpingectomy is the mainstay of treatment for EP, providing definitive treatment at the time of definitive diagnosis. Most EPs are amenable to a laparoscopic approach which has become a standard gynaecological procedure. Hospital stay is reduced compared with treatment by laparotomy and there is less potential for subsequent adhesion formation.
Laparoscopic salpingotomy Removal of the ectopic with conservation of the tube (salpingotomy) may be appropriate if the woman has only one fallopian tube or the contralateral tube is diseased. Salpingotomy is associated with a 5-10 per cent incidence of persistent trophoblast that may require further treatment. Where contralateral disease is absent, salpingotomy is not associated with a higher incidence of subsequent IUP (50 per cent compared with salpingectomy) but is associated with a slightly higher incidence of a future EP (15 per cent versus 10 per cent).
Non-surgical management may be attractive since it avoids surgical intervention, but inevitably means a small proportion of women will receive treatment for a presumed EP without confirmation by laparoscopy.
Conservative management of EP is controversial but may be appropriate for selected women who can be managed within a well-resourced unit and are given a clear explanation. Small EP with low and falling serum HCG can be managed successfully without intervention in up to 80 per cent of cases, but prolonged monitoring may be required and tubal rupture can occur.
Methotrexate is an antimetabolite that prevents growth of rapidly dividing cells such as trophoblast. It is used increasingly in non-surgical management of EP with overall success rates of 70-80 per cent. Direct injection of methotrexate into the EP under ultrasound guidance is feasible but is technically more demanding and offers no particular benefit over intramuscular administration.
Systemic methotrexate administration usually involves a single dose based on an estimate of
the woman's surface area and is associated with
a resorption rate of 90 per cent, a subsequent
IUP rate of 60 per cent and recurrent EP rate of
10 per cent. Following methotrexate administration, serial HCG monitoring is required. The woman must be made aware of the possibility of treatment failure and the necessity for subsequent surgery.
Side-effects of systemic methotrexate are seen in up to 20 per cent of cases and include stomatitis and alopecia. Methotrexate pneumonitis and severe neutropenia are rarely described complications.
1 Tay JI et al (2000) Ectopic pregnancy: Clinical Review. BMJ 320:916-19.
(www.bmj.com) Comprehensive review.
2 Management of tubal pregnancies. Clinical Green Top Guidelines, RCOG (www.rcog.org.uk). Evidence-based guidelines for the management of EP.
3 Ectopic Pregnancy Trust (www.ectopic.org.uk).
Information for health practitioners and patients.
4 NetDoctor (netdoctor.co.uk). Patient information on EP.