Importance of timing of gestational exposure to methotrexate for its teratogenic effects when used in setting of misdiagnosis of ectopic pregnancy

Abstract

Objective: To report a case of embryopathy due to misadministration of methotrexate in the setting of suspected ectopic pregnancy that resulted in a different pattern of malformations than is typically seen with methotrexate.

Design: Case report.

Setting: Community hospital.

Patient(s): A 30-year-old primigravida women exposed to methotrexate (50 mg/m(2)) at 5 6/7 weeks' gestation.

Intervention(s): The patient underwent amniocentesis because of abnormal results at the first-trimester genetic screening (low levels of pregnancy associated plasma protein A and hCG) and fetal echocardiogram because of single umbilical artery.

Main outcome measure(s): Fetal anomalies.

Result(s): The fetus was found to have a single umbilical artery, tetralogy of Fallot, and a "horseshoe lung," despite administration of high doses of folic acid. The pregnancy ultimately ended with fetal demise at 30 weeks.

Conclusion(s): As medical management of ectopic pregnancy becomes more common, practitioners should be cautious about the potential teratogenic effects in unrecognized intrauterine pregnancies and be able to diagnose the myriad defects, including cardiac anomalies, that could result from such exposure.