Urolithiasis in pregnancy

Abstract

Management of urolithiasis during pregnancy is often challenging, requiring close cooperation between urologist, radiologist, and obstetrician. Physiological dilatation of the upper urinary tract occurs commonly in pregnancy due to altered uretero-dynamics. Ultrasonography is the preferred screening modality. X-rays present inherent risks of ionizing radiation and thus radiographic techniques including intravenous urography and computed tomography (CT) are best avoided. Magnetic resonance urography (MRU) offers a safe alternative to urography. If MRU fails to make the diagnosis, CT with a lower dose of ionizing radiation can be used in high-risk pregnancy. Fortunately, with conservative management, 70%-80% of symptomatic calculi pass spontaneously without any sequelae. We propose a logical, evidence-based, clinical management plan to enable the diagnosis, with the least possible risk to the patient and the fetus. During the first and second trimesters, sonographically guided PCN or internal ureteral stent placement is usually the first line of treatment. Specifically, ureteroscopic extraction is reserved for stones <1 cm. We believe that ureteroscopy should be avoided in the presence of sepsis and for stones >1 cm. However, we consider ureteroscopy as a useful option, since it combines a diagnostic procedure with definitive treatment. Patients with complicated stone disease should be delivered near full-term, and then, definitive measures should be planned for the postpartum period. Finally, for patients who are not near full-term, temporizing procedures appear to be valid alternatives. Management of stones in pregnancy must, therefore, be tailored to fit the individual patient. © 2011 Springer-Verlag London Limited.