Pregnancy of unknown location: Frequently asked questions

What does this mean for me?

A Pregnancy of Unknown Location (PUL) is when you have a positive pregnancy test but a pregnancy could not be seen on ultrasound scan. There are three main reasons why this can occur:

• 1. The pregnancy is very early and it is too small to be seen on ultrasound scan.
• 2. The pregnancy has ended in a miscarriage and cannot be seen on ultrasound scan. It can take up to 3 weeks for the pregnancy hormone levels to drop to non-pregnant levels, which is why a pregnancy test may still be positive. This situation is more likely if you have recently had heavy bleeding.
• 3. The pregnancy has implanted outside the womb, called an ectopic pregnancy, but is too small to be visualised on ultrasound scan.

What will happen next?

You will have your pregnancy hormone (βHCG) level test. Some hospitals also take a test to assess the progesterone (ovarian hormone) level. The βHCG levels may then be repeated in 48 hours according to the protocol of your local Early Pregnancy Unit (EPU). A βHCG level rise of 63% over a 48-hour period (known as the ‘doubling time’) is usually (but not exclusively) associated with a pregnancy developing in the uterus. The pattern of these blood tests will help to guide further management including when to repeat further blood tests, urine pregnancy tests or a repeat ultrasound scan. This can be a stressful time, and it is natural to feel anxious while the location of your pregnancy is uncertain, particularly if you have had a pregnancy loss before. However, the time needed to get the right diagnosis is important and you will be supported throughout by your specialist team in the EPU. You will be advised to attend for further blood tests and scans to make a correct diagnosis of the pregnancy location and to offer you the right care and support. You will be able to contact the team with any queries or concerns you have during this time.

What worrying signs should I look out for?

The risk is that this may be an ectopic pregnancy (a pregnancy implanted outside the womb), which sometimes can cause life threatening internal (abdominal) bleeding. The risk of this happening is very low and your EPU team will guide. However, you should call your local EPU for advice or attend your local Accident and Emergency (A&E) department if you have of the following concerns:

• Vaginal bleeding: If you have any heavy bleeding with severe abdominal pain, fever, or offensive discharge you should seek urgent medical help. However, bleeding is pregnancy is common and may not actually be heavy. It is not always a sign of something serious but should always be investigated.
• Abdominal (tummy) pain: This typically occurs in the lower part of your abdomen, often on one side and can develop gradually or suddenly and may be quite intense. The pain may come and go and may sometimes be confused with ‘trapped wind’. Pain should also always be investigated in early pregnancy.
• Shoulder tip pain: This is pain around the shoulder blades, and you should seek urgent medical help if this happens. It may be linked with internal bleeding in the abdomen and irritation of the nerves in this area leads to shoulder tip pain.
• Diarrhoea: This may also be linked with internal bleeding like shoulder tip pain, as described above. In such cases there will also be abdominal pain and you should also seek urgent medical help if this happens.
• Ectopic pregnancy rupture: In addition to the above, any of the following symptoms could be a sign of ectopic rupture and requires urgent A&E attendance – constant, severe abdominal pain; nausea/vomiting; dizziness/feeling faint; looking pale.