Heterotopic gestation: another possibility for the emergency bedside ultrasonographer to consider.

Emergency bedside ultrasonography has become an important tool in differentiating an intrauterine from an ectopic pregnancy. As the odds of a heterotopic pregnancy were thought to be minute, some ultrasonographers and Emergency Physicians certified in bedside ultrasonography have taught that an intrauterine gestation with fetal heart tones clinches the diagnosis of intrauterine pregnancy. However, with the current rise in heterotopic gestations, this standard of care should be re-evaluated. If emergency bedside ultrasonography reveals an intrauterine gestation in the presence of either a moderate amount of free fluid in the pelvis or a co-existent ovarian cyst, one must consider and search for a heterotopic pregnancy.