Preventing ruptured ectopic pregnancy with a single serum progesterone.

Retrospective data on patients with documented ectopic pregnancies have demonstrated the potential usefulness of serum progesterone in decreasing the time to diagnosis. We report a prospective trial utilizing serum progesterone in the emergency department of a large city-county hospital. Sixty-seven ectopic pregnancies were document in the 582 patients screened; 54 (80.6%) had a progesterone level less than 15 ng/ml. Only one (1.5%) ruptured ectopic pregnancy was associated with a progesterone level greater than 25 ng/ml. There were 387 documented or presumed normal intrauterine pregnancies, 41 (10.6%) had progesterone concentrations of less than 15 ng/ml and 236 (61%) had a progesterone level greater than 25 ng/ml. We decreased minimum time of diagnosis from 48 to 72 hours to less than 24 hours by use of a progesterone screening protocol. During this time the percentage of ruptured ectopic pregnancies decreased from 79.2% to 38.8% (p less than 0.05). Because of its simple interpretation and 24-hour maximum delay, we conclude that the determination of serum progesterone should be used for ectopic pregnancy screening in all patients at risk for ectopic pregnancy, or at any time when the diagnosis is in question.