Pregnancies at the Uterotubal Junction: A Review of Terminology (Interstitial, Cornual, and Angular) and Recommendations for Management

Ectopic pregnancies are one of the most common causes of obstetric mortality worldwide. Interstitial ectopic pregnancies, defined as an extracavitary pregnancy within the portion of the Fallopian tube that transverses the myometrium, have reported mortality rates approximately seven times higher than all types of ectopic pregnancy combined. In contrast, intracavitary eccentric gestations, often labeled as "cornual" or "angular" pregnancies, have reportedly high rates of live birth. Unfortunately, the terms "interstitial," "cornual," and "angular" have long been used with varying diagnostic criteria and often interchangeably to describe a pregnancy near the uterotubal junction. The inconsistency in nomenclature and lack of clear diagnostic criteria to distinguish among these pregnancies has resulted in a paucity of data to provide accurate prognostic information and guide appropriate management. This review article aims to provide historical context for the terms "interstitial," "cornual," and "angular;" discuss previous and more recent innovations of diagnostic methods; and provide recommendations for concise terminology and inform management.