Analysis of three hundred fifteen ectopic pregnancies treated with single-dose methotrexate.

Objectives: The objective of this study was to review the largest single series of ectopic pregnancies treated with single-dose methotrexate reported to date.

Study Design: A review of 315 patients with unruptured ectopic pregnancies treated with single-dose methotrexate 50 mg/m2 from March 21, 1990, to March 1, 1997, was performed.

Results: Overall 287 patients were successfully treated with methotrexate for a success rate of 90.1%. Six patients electively withdrew and requested surgery within 1 week of starting therapy. Excluding withdrawals the overall success rate was 92.9%. Ten patients with an ectopic pregnancy > 3.5 cm but < or = 4 cm in size were treated for a 90% success rate. Forty-four patients with positive ectopic cardiac activity were treated with an 87.5% success rate.

Conclusions: This large series indicates that single-dose intramuscular methotrexate for treatment of ectopic pregnancy is associated with an excellent overall success rate.