This #TBT, we look at an insightful 2014 piece on ectopic pregnancies by Yasmin Sana, Senior Registrar Princess Royal University Hospital, Kings College NHS Foundation Trust.
What is ectopic pregnancy?
This is a term used when a pregnancy is implanted outside the womb. The normal site of implantation is within the womb. Most ectopic pregnancies fail during the early stages of development with rare exceptions where it develops to late gestation. Ectopic pregnancy is a potentially life threatening condition due to the risk of rupture and internal bleeding. If not diagnosed and managed on time, it can be dangerous for the mother.
How does ectopic pregnancy happen?
In a normal pregnancy the egg is fertilised by the sperm in the fallopian tube and the fertilised egg (ovum) then migrates into the womb where it attaches and starts growing. An ectopic pregnancy occurs when the fertilised egg fails to reach the uterus and starts to grow in other places. The most common site is the fallopian tube (98%) and rarely it can occur in other places in the pelvis such as ovary, cervix and even in a previous caesarean section scar.
How common is the condition?
Overall risk of ectopic pregnancy is different across different countries and populations. The incidence in the UK is 1-2 percent of all pregnancies. If a woman has had one ectopic pregnancy in the past, her risk of having another ectopic in future is increased to up to 15%.
Why does ectopic pregnancy occur?
Any condition that results in scarring of the fallopian tubes increases the risk of ectopic pregnancy. The conditions that can result in scarring of the fallopian tubes are sexually transmitted infections such as chlamydia, previous operations in the pelvis (for example caesarean section, appendectomy), endometriosis, sterilisation and surgery on fallopian tubes for fertility.
Women have a higher chance of developing an ectopic pregnancy if they have one or more of the following risk factors.
History of smoking, infertility (where woman has been trying long for pregnancy), assisted conception such as IVF (in vitro fertilization) and pregnancy in the presence of a contraceptive coil in the womb.
Women who are very young at first sexual intercourse (less then 18) and women above the age of 35 also have a higher risk of ectopic pregnancy.
What are the symptoms?
Pain is the most common symptom and women typically start to experience this about 6-7 weeks into the pregnancy. The fallopian tube (most common site of ectopic pregnancy) is a thin and delicate structure. As the ectopic pregnancy starts to grow in the fallopian tube, it causes pain. This is usually on one side in the lower abdomen but can be on both sides as well.
Some women do not have pain or any other symptoms until the ectopic pregnancy bursts and causes internal bleeding. This results in symptoms of feeling very weak and unwell, pain in the abdomen, feeling faint or passing out. These women may also experience shoulder tip pain.
Bleeding from the vagina is also very common; it can be very light in the form of spotting or can be heavy like a period. Some women also pass clots.
Bladder or bowel symptoms:
Women may have pain on passing urine or opening bowels. In cases where internal bleeding has started, women may experience pain and need to open their bowels frequently or develop loose stools. These symptoms should not be ignored and medical advice should be sought as soon as possible.
Missed period and positive pregnancy test:
As with normal pregnancy, missed period is the first symptom that alerts women that she may be pregnant. An over the counter pregnancy test is very sensitive in detecting pregnancy. Any woman with missed period and positive pregnancy test with one or more of the above symptoms should contact her GP or attend A/E (accident and emergency) if symptoms are severe and the Doctor is not available.
How is the diagnosis made?
Most of the ectopic pregnancies can be diagnosed by an internal ultrasound scan (transvaginal scan). In cases where an ectopic pregnancy cannot be seen on the initial scan and a woman has no symptoms, there is a possibility that the pregnancy is too early to be seen on scan. In such cases blood tests to check the pregnancy hormone level may aid in reaching a final diagnosis. In such cases the other possibilities are a miscarriage or still an ectopic pregnancy which will be detected later.
In women where an ectopic pregnancy cannot be seen on the initial scan and they have severe pain, surgery may be required to establish the cause of pain. This is typically done as keyhole surgery.
How is ectopic pregnancy treated?
The treatment depends on the site of the ectopic pregnancy, its size, symptoms and also on the level of the pregnancy hormone in the blood test.
1. Expectant management
Women who have a small size ectopic pregnancy, have minimal or no symptoms and pregnancy hormone level is low, can be managed without any intervention as these pregnancies tend to resolve naturally. These women should however have regular follow up until the pregnancy is resolved as in small number of cases ectopic pregnancy can still rupture and due to risk of internal bleeding, emergency surgery may be required in these cases.
2. Surgical management
This means an operation to remove the ectopic pregnancy. In most cases it involves keyhole surgery and the fallopian tube containing the ectopic pregnancy is removed. In women who have become unwell due to ruptured ectopic pregnancy, an open operation may be required to quickly stop the bleeding however in some cases it is still possible to perform keyhole surgery. Open surgery may also be required in women who have a large body weight or have had several previous operations on their abdomen, making keyhole surgery more risky.
3. Medical management
This is carried out using an injection called methotrexate. Women can only be given this medication if they have minimal or no symptoms have a relatively small size ectopic pregnancy, and the blood pregnancy hormone level is not very high. Most women will need one injection and require regular monitoring to check the blood pregnancy hormone level until the pregnancy is resolved. It can take several weeks before the pregnancy is completely resolved. Some women may require a second injection if the pregnancy hormone level fails to drop with one injection. Women, who have this injection, still are at risk of having the ectopic pregnancy ruptured and need for emergency surgery. They should report to the Doctor or attend A/E if they have pain.
Women are advised not to get pregnant for three months after this injection due to its harmful effects on the developing pregnancy.
What should I do if I am pregnant and had an ectopic pregnancy before?
Women, who had an ectopic pregnancy in the past, are at increased risk of having this condition again in the future. You should ask your Doctor to refer you for a scan in early part of pregnancy (around 6 weeks) to ensure that the pregnancy is growing in the right place.
What are my chances of conception after having surgery for ectopic pregnancy?
After surgery for ectopic pregnancy where one fallopian was removed women can still become pregnant if the other tube is healthy. Your Doctor who performed the surgery should be able to provide this information after surgery. The fallopian tube can pick the egg released from the ovary on the other side and there is high chance that the future pregnancy will be in the womb.
By Yasmin Sana MBBS, MRCOG, Senior Registrar Princess Royal University Hospital, Kings College NHS Foundation Trust.