Traditional methods of urinary diversion in pregnancy include retrograde passage of ureteral catheter or stents and operative nephrostomy. These techniques are, however, associated with the use of anesthesia, are technically difficult to perform, and may induce labor. We report the use of percutaneous nephrostomy in four pregnant patients, two with obstruction due to ureteral calculi and two with infected hydronephrosis. The procedure provided rapid relief from pain and pyosepsis, and allowed uneventful continuation of the pregnancy to full-term, with preservation of renal function.