Time and the risk of ruptured tubal pregnancy.

Objective: Tubal pregnancy remains an important cause of maternal morbidity and mortality. We sought to quantify the relationship of time between symptom onset and treatment and the risk of tubal rupture.
Methods: We reviewed inpatient, clinic, and physician office charts of 221 women with tubal pregnancy. We assessed the conditional risk of rupture with passing time and other factors related to rupture.
Results: Time between symptom onset and treatment varied from 3 hours to 66 days with an average of 7 days. There was a 32% rupture rate. The conditional risk of rupture was highest within the first 48 hours of symptom onset (5-7%). The risk dropped, leveled off, and remained fairly steady at approximately 2.5% per 24 hours of untreated symptoms. Classic tubal pregnancy signs, symptoms, and tests were not helpful in predicting rupture.
Conclusion: The rate of rupture is highest in women with the shortest times between symptom onset and treatment. With passing time, the risk declines, but remains steady despite women's getting into care.
Level of Evidence: II-2