Challenges on percutaneous nephrolithotomy in pregnancy: Supine position approach through ultrasound guidance.

Urolithiasis in pregnancy represents a major diagnostic and therapeutic challenge to the obstetrician, urologist, radiologist and anesthetist. It is a cause of major concern, considering the potential adverse effects of radiation exposure and of any invasive surgical procedure and anesthesia on the mother and fetus. Fortunately, with conservative management, 70-80% of symptomatic calculi pass spontaneously with no sequel. However, fever, infection, uncontrolled pain and progressive hydronephrosis are indications for surgical intervention when retrograde placements of a ureteral stent or a percutaneous nephrostomy tube are the most traditional options. The recent technological advances in stone fragmentation devices and the administration of safe anesthesia have forced clinicians to embark on more definitive stone management techniques in pregnancy. Ureteroscopy is considered the first definitive treatment of obstructive ureteral calculi during all trimesters of pregnancy, but also has limitations. Although generally avoided during pregnancy, percutaneous nephrolithotomy can be a good treatment choice in selected patients.