Expectant management

No evidence of tubal rupture

Minimal pain or bleeding

Patient reliable for follow-up

Starting β-hCG level less than 1,000 mIU per mL (1,000 IU per L) and falling

Ectopic or adnexal mass less than 3 cm or not detected

No embryonic heartbeat

Medical management with methotrexate

Stable vital signs and few symptoms

No medical contraindication for methotrexate therapy (e.g., normal liver enzymes, complete blood count and platelet count)

Unruptured ectopic pregnancy

Absence of embryonic cardiac activity

Ectopic mass of 3.5 cm or less

Starting β-hCG levels less than 5,000 mIU per mL (5,000 IU per L)

Dosage: single intramuscular dose of 1 mg per kg, or 50 mg per m2

Follow-up: β-hCG on the fourth and seventh posttreatment days, then weekly until undetectable, which usually takes several weeks

Expected β-hCG changes: initial slight increase, then 15 percent decrease between days 4 and 7; if not, repeat dosage or move to surgery

Special consideration: prompt availability of surgery if patient does not respond to treatment

Surgical management

Unstable vital signs or signs of hemoperitoneum

Uncertain diagnosis

Advanced ectopic pregnancy (e.g., high β-hCG levels, large mass, cardiac activity)

Patient unreliable for follow-up

Contraindications to observation or methotrexate