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Updates in the Management of Pregnancy of Unknown Location: A Focus on Expediting and Streamlining Care

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Abstract

Purpose of Review

This review will highlight advances in pregnancy of unknown location (PUL) management and advocate for incorporating desiredness and triaging of low-risk patients to less intensive follow-up when possible.

Recent Findings

After the initial diagnosis of a PUL, fluid is sometimes seen inside the uterine cavity on transvaginal ultrasound. A retrospective study looked at the incidence of ectopic pregnancy in patients who have intrauterine fluid collections and found that the risk of ectopic pregnancy in this population is very low. For patients with PUL and an intrauterine fluid collection, a follow-up ultrasound in 1 week can be offered. For patients with undesired PULs, mifepristone and misoprostol can be given and has been shown to lead to shorter time to diagnosis and pregnancy resolution compared to establishing a final diagnosis prior to initiating medication abortion. However, abortion efficacy is lower in patients with undesired PULs. Therefore, medication abortion can be initiated in this population in the carefully selected patient and with close interval follow-up. Multiple algorithms exist and are available for clinicians to use to risk stratify patients with PUL; the M4 model was found in a systematic review to outperform other models. For patients with persistent PULs, active management is more successful at pregnancy resolution than expectant management.

Summary

Clinicians should provide active management to patients with undesired pregnancy of unknown location. Selected patients at low risk of ectopic pregnancy can be triaged to less intensive follow-up in order to reduce unnecessary blood-draws and visits.

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References

Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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  1. Obstetrics and Gynecology, University of California Davis, 4860 Y St, Suite 2500, Sacramento, CA, 95817, USA

    Anne N. Flynn

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  1. Anne N. Flynn
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Correspondence to Anne N. Flynn.

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Flynn, A.N. Updates in the Management of Pregnancy of Unknown Location: A Focus on Expediting and Streamlining Care. Curr Obstet Gynecol Rep 12, 64–69 (2023). https://doi.org/10.1007/s13669-023-00355-w

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