Pregnancy of unknown location (PUL)

A pregnancy of unknown location (PUL) is defined to occur when, in a woman with a positive pregnancy test, an empty uterus is visualized on transvaginal scan (TVS), with no signs of intrauterine pregnancy (IUP) or an extra uterine (ectopic) pregnancy (EP). The increasing prevalence of PUL is due to easy access to urine pregnancy tests, better availability of ultrasound scans and increased anxiousness of the patient to confirm a pregnancy after missing the next normal menstrual cycle. The outcome of such a PUL can be continuation of normal pregnancy, failing pregnancy, ectopic pregnancy and persistent PUL. Various tests have been devised to predict the outcome successfully and protocols of management have been charted to manage the condition with minimal patient visits. These involve repeated blood tests, transvaginal ultrasound scans and application of mathematical models. In this study, an electronic search was conducted to review the effectiveness of the predictive tests and details regarding management protocols for PUL. It was found that the protocols were feasible for the developed countries and tertiary care centres. A practical approach for the management of PUL which can be adaptable globally without compromising on the safety of the patient was attempted to be developed from the inferences drawn in previous studies regarding merits and demerits of the methods used and the life threatening severity of the varied outcomes. Since pregnancy continuation is a favorable outcome, and failing pregnancy is not life threatening, the outcome of ectopic pregnancy and persistent PUL were the point of focus in terms of development of effective prediction and practical management guidelines.