Classically ectopic pregnancy presents with abdominal pain and vaginal bleeding in a woman who has missed a period and is pregnant.
The first step in diagnosis is paying attention to these symptoms, both on the part of the woman and her doctor.
Another thing taken into consideration are the risk factors for ectopic pregnancy, which include:
Previous ectopic pregnancy
History of PID
Previous sterilisation or tubal surgery
Current IUCD use
Not all women have these symptoms therefore other investigations are required
The first, is a urine pregnancy test, if this is positive the next investigation will be a pelvic ultrasound scan. This is usually done vaginally.
The (Ultrasonographer) scanner looks to see whether a pregnancy is identified in the womb.
If this is the case then an ectopic pregnancy can be ruled out in the majority of cases except in women who have a pregnancy in the right place as well as an ectopic pregnancy.
This is called heterotrophic pregnancy and occurs in about 1:30,000 pregnancies but the incidence may be as high as 1:1000 in women who have undergone assisted conception
If the pregnancy is not where it is supposed to be that is in the womb the explanation may be:
It is too early to see the pregnancy (it is sometimes difficult to see pregnancies on ultrasound at less than 6 weeks into the pregnancy)
It may be a miscarriage
Or early ectopic pregnancy
Other things that the scanner looks for is whether there is fluid in the pelvis that may represent bleeding
Or whether they can see the pregnancy mass outside the uterus on the tube
If these findings are identified then an ectopic pregnancy can be inferred and
Though experienced and well-trained ultrasonographers may be able to find ectopic pregnancies on the tube they can sometimes be missed.
Therefore if the location of the pregnancy remains unknown after the scan it is termed “pregnancy of unknown location”, so to help with the diagnosis the doctors will advise a blood test to measure serum bHCG which is a hormone produced by pregnancy.
As a general rule if the estimation of this hormone is greater than 1000IU it should be possible to identify the pregnancy on ultrasound scan
What happens next will depend on symptoms
If symptoms are mild with levels about 1000IUand the pregnancy location cannot be identified the doctors will advise a further blood test too look at either the rate of rise or fall of the hormone. The blood test is performed every 48hrs and doctors will advise that if it is safe to go home, women should refrain from intercourse and return to hospital if the pain worsens.
If the levels fall and the symptoms get better doctors may opt to follow things up until the levels become negligible
If the levels rise as these levels tend to double every 48 hours a repeat scan is organised to try and look for the site of the pregnancy.
Added to this test the doctors may ask for another hormone test called progesterone to help with the diagnosis
Doctors will continue this follow up process taking symptoms, levels of HCG and risk factors and scan findings in order to make a diagnosis.
If on the other hand symptoms worsen or if there is a rise in bHCG and or the ectopic pregnancy is diagnosed a laparoscopy may be advised to diagnose and treat the ectopic pregnancy.