Early Pregnancy - Ectopic Pregnancy

Question 1

What is an Ectopic Pregnancy?

Answer 1

Implantation of a fertilised ovum outside the uterus.

Question 2

What are the commonest sites of Ectopic Pregnancies? (5).

Answer 2

1. Fallopian Tube - Ampulla and Isthmus.
2. Corneal Region (Entrance to Fallopian Tube).
3. Ovary.
4. Cervix.
5. Abdomen.

Question 3

Epidemiology of Ectopic Pregnancy (2).

Answer 3

1. 0.5% of all Pregnancies.

2. 97% are Tubal. 3% are non-Tubal.

Question 4

Main Differential Diagnosis of Ectopic Pregnancies (1).

Answer 4

Miscarriage - both present with pain and vaginal bleeding but pain is often the first and dominant symptom in an ectopic pregnancy.

Question 5

What is a Pregnancy of Unknown Location (PUL)?

Answer 5

A woman has a positive pregnancy test, yet there is no evidence of a pregnancy on an Ultrasound Scan. An ectopic cannot be excluded yet.

Question 6

How can PULs be monitored?

Answer 6

Serum hCG tracking over time - repeat after 48 hours to see change from a baseline.

Question 7

Rationale of PUL monitoring.

Answer 7

The developing syncytiotrophoblast produces hCG in an intrauterine pregnancy - hCG should double every 48 hours.

Question 8

Results of PUL monitoring (3).

Answer 8

1. A rise of >63% after 48 hours is likely to be an intrauterine pregnancy. Repeat US scan to confirm 1-2 weeks later. Pregnancy is visible usually when hCG exceeds 1500IU/L.
2. A rise of <63% can indicate an ectopic. Review and closely monitor.
3. A fall of >50% can indicate a miscarriage. Perform a urine pregnancy test after 2 weeks to confirm completion of miscarriage.

Question 9

Risk Factors of Ectopic Pregnancy (8).

Answer 9

1. Previous Ectopic Pregnancy.
2. Previous PID.
3. Previous Surgery to Fallopian tubes.
4. IUD Coils & POPs (due to Fallopian tube Ciliary Dysmotility).
5. Older Age.
6. Smoking.
7. Endometriosis (Adhesion Formation).
8. IVF (3% of IVF Cases).

Question 10

Main Clinical Features of Ectopic Pregnancies (3).

Answer 10

1. Constant Lower Abdominal Pain/Tenderness in RIF/LIF (unilateral tubal spasm - tends to be 1st symptom).
2. Vaginal bleeding (less than normal period and may be dark brown).
3. Chandelier Sign (cervical motion tenderness/cervical excitation - pain when moving the cervix in bimanual examination).

Question 11

Additional Clinical Features of Ectopic Pregnancies (2).

Answer 11

1. Dizziness/Syncope (Blood Loss).

2. Shoulder Tip Pain or Pain on Defecation/Urination (Peritonitis).

Question 12

Aetiology of Shoulder Tip Pain in Ectopic Pregnancies.

Answer 12

The irritation of diaphragm by blood results in referred shoulder tip pain because the diaphragm and supraclavicular nerves share the same C3-C5 dermatomes.

Question 13

Aetiology of Bleeding in Ectopic Pregnancies (3).

Answer 13

1. Decidual breakdown in uterine cavity due to sub-optimal b-hCG levels.
2. Bleeding from a ruptured ectopic is usually intra-abdominal and not vaginal.
3. Trophoblast invades the tubal wall and can dislodge the embryo.

Question 14

Investigations in Ectopic Pregnancies (5).

Answer 14

1. Investigation of Choice = Transvaginal Ultrasound Scan.
2. Typical Finding = Gestational Sac with yolk sac/foetal pole in Fallopian tube.
   Other findings :
3. ‘Blob’/’Bagel’/’Tubal Ring’ Sign = Non-Specific Mass containing empty gestational sac.
4. Mass representing tubal ectopic moves separately to the ovary. The Corpus Luteum can look similar but it will move with the ovary.
5. ‘Pseudogestational Sac’ = an empty uterus/fluid in the uterus mistaken to be gestational sac.

Question 15

General Management of Ectopic Pregnancies (5).

Answer 15

1. Pelvic Pain/Tenderness + Positive Pregnancy Test = EPAU/Gynaecology Service.
2. Expectant Management.
3. Medical Management.
4. Surgical Management.
5. All ectopic pregnancies need to be terminated as they are not viable.

Question 16

Expectant Management of Ectopic Pregnancies (2).

Answer 16

1. Awaiting Natural Termination.

2. Need careful follow-up with close monitoring of hCG.

Question 17

Criteria for Expectant Management for Ectopic Pregnancies (6).

Answer 17

1. Follow-Up Needs to be Possible.
2. Unruptured Ectopic.
3. Adnexal (Foetal) Mass < 35mm.
4. No Visible Heartbeat.
5. No Significant Pain.
6. hCG is below 1500 IU/L.

Question 18

Criteria for Medical Management for Ectopic Pregnancies (3).

Answer 18

1. All of Expectant Management Criteria.
2. hCG is below 5000 IU/L.
3. Confirmed absence of intrauterine pregnancy on US Scan.

Question 19

Medical Management of Ectopic Pregnancies (3).

Answer 19

1. IM Injection of Methotrexate into buttock to halt progress of pregnancy and spontaneous termination (teratogenic).
2. Advised not to get pregnant for 3 months.
3. Monitor hCG levels regularly after - should decline >15% in day 4-5 or repeat dose.

Question 20

Mechanism of Action of Methotrexate.

Answer 20

Anti-folate cytotoxic agent that disrupts the folate-dependent cell division of the developing foetus.

Question 21

Adverse Effects of Methotrexate (4).

Answer 21

VANS :-

1. Vaginal Bleeding.
2. Abdominal Pain.
3. N&V.
4. Stomatitis.

Question 22

Criteria for Surgical Management of Ectopic Pregnancies.

Answer 22

Anyone who does not meet the criteria for Expectant or Medical Management (most patients).

Question 23

Surgical Management of Ectopic Pregnancies (4).

Answer 23

1. 1st Line = Laparoscopic Salpingectomy (GA + Key-Hole Removal of Affected Fallopian tube with Ectopic).
2. Laparoscopic Salpingotomy (in women with increased risk of infertility due to damage to other tube; avoid removing Fallopian tube and remove ectopic only).
3. Anti-Rhesus D Prophylaxis to Rhesus Negative Women.
4. Increased Risk of Failure to Remove Ectopic with Salpingotomy (1 in 5).