How ectopic pregnancy is diagnosed
Ectopic pregnancy can be notoriously difficult to diagnose. The reason for this is that the condition can often present with symptoms which can be suggestive of other more usual conditions, such as gastroenteritis, miscarriage or even appendicitis.
Doctors rely on women to give them clear histories about their symptoms. The more you can tell a doctor about what has changed, what feels different and what is worrying you, the more likely they are to be able to diagnose you.
EPT advice is that all women of childbearing age presenting with abdominal pain and or bleeding, should be considered pregnant until proven otherwise. The first and most useful basic first test is a urinary pregnancy test. Good practice would then be to investigate with a transvaginal ultrasound scan. An initial scan will detect over 70% of ectopic pregnancies - however some will not be seen and the pregnancy may be labelled as a pregnancy of unknown location or PUL for short. If this is the case you may have blood taken to measure serum progesterone and/or beta hCG, usually with the beta hCG level repeated 48 hours later.
Doctors are at liberty to follow their own hospital protocols and in the UK if they use any national guideline at all, it will be Greentop Guideline 21. The management of tubal pregnancy.
Diagnosis in hospital is improving all the time, particularly because more and more district trusts are setting up Early Pregnancy Assessment Units. Modern transvaginal (TVS) ultrasound scans on modern equipment provide better images than a few years ago, and repeated use of sensitive blood pregnancy tests (hCG) can help tell doctors how the pregnancy is progressing, even if your urine pregnancy test (standard GP or chemist urine test) is not positive or has stopped being positive.
Early pregnancy assessment usually involves an ultrasound scan as the baseline observation. If at this point a pregnancy can be seen in the uterus - that is, a gestation (pregnancy) sac, a foetal pole and a beating heart - the chance of a coexisting ectopic pregnancy, whilst possible, is very slim.
If signs of pregnancy can be seen in the uterus (usually a yolk sac but either no embryo or if the embryo is too small to expect to see a heartbeat) this situation is given the label of an intrauterine pregnant of uncertain viability or PUV or IPUV. In order to see if the pregnancy is developing normally you should be offered as a repeat scan at least a week to ten days later. In these circumstances of a confirmed intrauterine pregnancy it is unlikely that blood test are going to give any useful information about the pregnancy.
If no pregnancy can be seen in the uterus, or there is a small gestation sac in the uterus – but without a yolk sac or embryo – the pregnancy will be labelled as a pregnancy of unknown location or PUL. It is important to understand that PUL is not a diagnosis – it is a label given until the final location of the pregnancy can be identified with certainty. In the event of a PUL blood will be taken to measure serum progesterone and hCG and the hCG test repeat 48 hours later. Based on this information the clinicians seeing you will decide if you are at low risk of ectopic pregnancy – in which case they may arrange a blood or urine test at an interval or at high risk where they will often repeat the scan or blood test in 48 hours. Until the location of the pregnancy is known definitively or the serum hormone levels have decreased to below pregnancy levels – there is a risk of complications associated with an as yet undiagnosed ectopic pregnancy. For every 100 pregnancies labelled as a PUL about 10 will subsequently be found to be ectopic, and not all of these will need treatment.
If no pregnancy can be seen in the uterus but there is evidence of free fluid in your abdomen and or a possible mass in the approximate location of one of your fallopian tubes, the doctor would then be likely to diagnose a possible ectopic pregnancy
If you are stable, your pulse and blood pressure are within normal limits and you are not bleeding heavily or in severe pain and if you do not have signs of dizziness or fainting, the doctor will discuss the treatment options with you.
Unfortunately, a number of women present for assessment after a time when there are options for treatment. If you are bleeding heavily, in severe pain or have signs of dizziness or fainting, the doctor will probably suggest an exploratory surgical operation called a laparoscopy which done via keyhole to allow him or her to take a look inside your abdomen to see what might be happening.
If this is the case, the doctor will need to obtain your consent for the exploratory operation and at the same time will discuss with you the need to do a more involved surgical procedure if he or she finds an ectopic pregnancy.