Medical Management of Ectopic Pregnancy
General measures Medicine treatment Referral ICD-10 code: O00.0-2/O00.8-9 GENERAL MEASURES Ruptured or suspected rupture of an ectopic pregnancy should be managed with urgent resuscitation and surgery. There must be certainty that there is no viable intra-uterine pregnancy. The discriminatory zone is the β-hCG level above which an ultrasound is likely to visualise a gestational sac within t
ICD-10 code: O00.0-2/O00.8-9
GENERAL MEASURES
- Ruptured or suspected rupture of an ectopic pregnancy should be managed with urgent resuscitation and surgery.
- There must be certainty that there is no viable intra-uterine pregnancy.
- The discriminatory zone is the β-hCG level above which an ultrasound is likely to visualise a gestational sac within the uterus in a normal intra-uterine pregnancy (>1500 IU/L for a transvaginal ultrasound).
- If the initial β-hCG level is below the discriminatory threshold (or level) to diagnose a pregnancy on transvaginal ultrasound, or the ultrasound cannot definitively identify an intrauterine or extra-uterine gestation, then serial β-hCG measurements are necessary to differentiate between a growing, potentially viable pregnancy, and a non-viable pregnancy.
- A minimum rise in β-hCG of 53% every two days is expected for a potentially viable pregnancy in women who present with symptoms of pain and/or vaginal bleeding.
- Repeat the β-hCG in 48 hours:
- If the level has dropped, conservative management may be appropriate.
- If the level has increased by >50% or is now above the discriminatory zone, repeat the ultrasound scan to exclude an intra-uterine pregnancy before methotrexate is administered.
MEDICINE TREATMENT
Methotrexate should be the first-line management for women who are able to return for follow-up and who have the following characteristics:
- haemodynamic stability and no significant pain.
- an unruptured ectopic pregnancy with a mass <35 mm and no visible heartbeat.
- low serum β-hCG, ideally less than 1500 IU/L but can be up to 5000 IU/L.
- certainty that there is no intrauterine pregnancy.
- willingness to attend for follow-up.
There are single and multiple dose methotrexate protocols available. The single dose protocol is less expensive, requires less intensive monitoring and does not require folinic acid rescue. The single dose protocol is recommended for the medical management of ectopic pregnancy.
Methotrexate single-dose protocol:
Day 1: Check urea, creatinine, ALT and FBC to exclude abnormalities.
- Methotrexate, IM, 50 mg/m2 of body surface area (BSA).
- BSA may be calculated based upon height (cm) and weight (kg) on the day of treatment using the following formula:
𝐵𝑆𝐴 (𝑚2 ) = √ (𝐻𝑒𝑖𝑔ℎ𝑡 𝑥 𝑊𝑒𝑖𝑔ℎ𝑡)/ 3600
Day 4: Repeat β-hCG.
Day 7: Repeat β-hCG.
If the decrease from day 4 to day 7 is ≥15%:
- Continue with weekly β-hCG until undetectable.
If decrease <15% and patient still fulfils the criteria for medical management:
- Methotrexate, IM, 50 mg/m2BSA.
Day 14: Repeat β-hCG.
CAUTION
- Methotrexate is associated with blood disorders and is hepatotoxic.
- Caution patients and their carers to immediately report the onset of any feature of blood disorders (e.g. sore throat, bruising, and mouth ulcers), liver toxicity (e.g. nausea, vomiting, abdominal discomfort and dark urine), and respiratory effects (e.g. shortness of breath).
REFERRAL
- If the decline in β-hCG is still <15% on day 14 after two doses of methotrexate, refer for specialist care.
Standard Treatment Guidelines and Essential Medicines List for South Africa Adult Hospital _Chapter 5: Gynaecology; Version 1.0, 2020-4_June 2024