Tubal ectopic pregnancy: diagnosis and management

Ectopic pregnancy is the gynaecological emergency par excellence and remains the leading cause of pregnancy-related first trimester deaths in the UK. Its prevalence continues to rise because of increases in the incidence of the risk factors predisposing to ectopic pregnancy. Classically, the diagnosis is based on a history of pelvic pain associated with amenorrhoea, a positive pregnancy test with or without slight vaginal bleeding. While the immediate differential diagnosis includes threatened or inevitable miscarriage, the likelihood of ectopic pregnancy is increased if transvaginal sonography (TVS) reveals an empty uterine cavity, and is confirmed if an adnexal mass with or without an embryo is seen. However, the diagnosis is often not that simple, especially when the patient presents early, has minimal pain, is haemodynamically stable, and TVS shows an empty uterus but no obvious adnexal mass. This could then be an early intrauterine pregnancy, or could indeed be an ectopic-a diagnosis of pregnancy of unknown location is made while additional investigations are made. The latter usually include serial measurements of serum beta human chorionic gonadotrophin (beta-hCG) and repeat TVS. Changes in beta-hCG levels in normal, failing and ectopic pregnancy are now reasonably well characterised, and at early stages of presentation where the risk of rupture of an ectopic are minimal, the patient can often be managed as an outpatient while the diagnosis is pursued. In the patient who presents with pain and haemodynamic instability, the diagnosis is often obvious, and the management is immediate laparotomy. However, in modern gynaecological practice in the developed world the vast majority of ectopic pregnancies present early, and the general consensus is that laparoscopic management offers both economic and aesthetic advantages, and should be used whenever possible. Salpingectomy (excision of the fallopian tube containing the ectopic) is performed if the contra-lateral tube is healthy, while salpingotomy (linear incision made in the fallopian tube with removal of ectopic pregnancy and conservation of tube) is performed if the contra-lateral tube is unhealthy. Medical therapy using methotrexate given systemically or injected directly into the ectopic pregnancy is an option occasionally used with good results. There appear to be no major differences in subsequent fertility outcomes, or risk of recurrence of ectopic pregnancy, between the surgical or medical treatments. Although the rates of ectopic pregnancy are not falling in the developed world, mortality and morbidity are falling mainly due to early and improving diagnostic and treatment modalities. Mass screening and treatment of Chlamydia in the young, sexually active populations, and education regarding risk factors, may in future result in a reduction in the rates. Lack of resource mean that the picture may remain dismal for some time to come in the developing world, but the development of basic protocols, improved training and the infusion of basic resources may go a long way to improving the situation.