A Pregnancy of Unknown Location (PUL) is when you have a positive pregnancy test but we cannot see the pregnancy on ultrasound.
There are three possible reasons:
- The pregnancy is too early to see on a scan. Home pregnancy testing kits are extremely sensitive and can sometimes detect the pregnancy hormone just a few days after conception. However, a pregnancy may not be seen on ultrasound until approximately 5 and a half weeks of gestation.
- An early miscarriage has occurred. The pregnancy may have started but may not be continuing to grow or if you have had bleeding, you may have passed the pregnancy.
- The pregnancy is growing outside the uterus (womb) most commonly in the fallopian tube. This is called an ectopic pregnancy. Ectopic pregnancy is potentially life threatening if ignored. Until we can see a pregnancy inside the womb, we cannot exclude an ectopic pregnancy.
Your nurse or midwife at BPAS will talk to you about the likelihood of these possibilities occurring based on your medical history.
Wait and rescan
If you do not have pain and bleeding and your period dates are compatible with a pregnancy that would be too early to see on scan, then we will scan you again in a week’s time when we should be able to see more clearly.
It is important that you are aware that we have not ruled out an ectopic pregnancy and if you have any pain or bleeding or feel unwell before you are due to come back to BPAS, you must seek medical attention straight away. you can contact the BPAS aftercare line, the clinic where you were seen, or go to A&E.
Referral to Early Pregnancy Assessment Unit (EPAU)
If you have had pain or bleeding or your period dates are not compatible with not being able to see the pregnancy, we may need to refer you for a more detailed assessment at an Early Pregnancy Assessment Unit (EPAU). They can perform a more detailed scan and take blood tests that can give more information to exclude or confirm an ectopic pregnancy.
- In a normal pregnancy that is in the uterus (womb), we expect the pregnancy hormone level to double every 48 hours.
- In an ectopic pregnancy the level will not double but will rise slightly or stay the same.
- If a miscarriage has occurred, then the level should come down.
If an ectopic pregnancy is excluded and you have not had a miscarriage, you can return to BPAS to arrange treatment.
An ectopic pregnancy is one that grows outside the uterus (womb). Often, an ectopic pregnancy grows in one of the fallopian tubes. Around 1% of pregnancies are ectopic. An ectopic pregnancy is very serious and can be life threatening.
An ectopic pregnancy can happen to any woman, but some conditions make it more likely. These include:
- having had an ectopic pregnancy in the past
- being sterilised (tubal ligation) or surgery on your fallopian tubes
- a history of Pelvic Inflammatory Disease (PID) with damage to the fallopian tubes
- an intrauterine device in place such as the copper ‘coil’, Mirena, or levosert at the time of getting pregnant
- older age
If you are scheduled to come back to BPAS in a week for another scan, you should know about worrying signs or symptoms to watch out for. These are:
- lower abdominal pain, especially if on one side and severe
- pain under the ribs or in the shoulders
- fainting or feeling lightheaded
- vaginal bleeding.
If you have any of these, seek medical advice immediately from:
- the BPAS Aftercare Line 0300 333 68 28 (or +44 1789 508 210)
- the nearest A&E department or Early Pregnancy Assessment Unit
If you need any more information you should speak to a BPAS nurse or midwife, but you can also talk to your GP or call the NHS non-emergency line by dialing 111.