Differentiating pregnancies near the uterotubal junction (angular, cornual, and interstitial): a review and recommendations

Abstract

Eccentrically located intracavitary pregnancies, which include pregnancies traditionally termed as cornual and/or angular, have long presented complex diagnostic and management challenges given their inherent relationship to interstitial ectopic pregnancies. This review uses the existing literature to discriminate among interstitial, cornual, and angular pregnancies. Current arguments propose the outright abandonment of the terms cornual and angular may be justified in favor of the singular term, eccentric pregnancy. Disparate definitions and diagnostic approaches have compromised the literature’s ability to precisely describe prognosis and ideal management practices for each of these types of pregnancies. Standardizing the classification of these pregnancies near the uterotubal junction is important to unify conservative, yet safe and effective management strategies. We advocate the use of early first trimester ultrasound to correctly differentiate between eccentric pregnancy and interstitial ectopic pregnancy as current research suggests substantially better outcomes with correctly diagnosed and expectantly managed eccentric pregnancies than past investigations may have shown. The expectant management of eccentric pregnancies will often result in a healthy term pregnancy, while interstitial ectopic pregnancies inherently have a poor likelihood of progressing to viability. When the terms and diagnosis of cornual, angular, and interstitial pregnancy are indistinct, there is substantial risk of intrauterine pregnancies to be inappropriately managed as ectopic pregnancies. Until we standardize terms and criteria, it will remain difficult, if not impossible, to determine true risk for pregnancy loss, preterm labor, abnormal placentation, and uterine or uterotubal rupture. The development of best practice guidelines will require standardized terminology and diagnostic techniques.

The elusive diagnosis and emergent management of a late-presenting ruptured interstitial pregnancy: a case report

“…Ectopic pregnancies account for 2 % of all pregnancies but are the cause of nearly 3 % of maternal deaths in the United States [ 1 ]. While interstitial pregnancies make up 2 to 4 % of ectopic pregnancies, they are associated with significant mortality, accounting for 20 % of all deaths associated with ectopic pregnancies [ 2 , 3 ].…”

“…However, each of these has a specific definition. A cornual pregnancy is most accurately defined as one occurring “in the rudimentary horn of a uterus with a Mullerian anomaly,” though many practitioners use this term to describe any pregnancy occurring near the cornua [ 3 ]. Angular pregnancies are classified as occurring within the uterine cavity but just medial to the uterotubal junction.…”

“…Angular pregnancies are classified as occurring within the uterine cavity but just medial to the uterotubal junction. Interstitial pregnancies, by contrast, are gestations occurring in the most proximal portion of the fallopian tube, embedded in myometrium, and thus are considered extrauterine because they are not within the uterine cavity [ 3 ].…”

“…Such distinctions are exceedingly important as management of these conditions varies greatly. Whereas eccentrically located intrauterine pregnancies often result in healthy term pregnancies, interstitial ectopic pregnancies are rarely viable, with a rupture rate of approximately 15 % [ 3 ].…”

Laparoscopic Treatment of an Interstitial Ectopic Pregnancy

“…An interstitial pregnancy represents an extremely rare variant of ectopic pregnancy (EP), accounting for 2% to 4 % of all cases [1−4], and heavy intra-abdominal, lifethreatening bleeding can develop [3,5].…”