Introduction Urolithiasis can complicate up to 1 in 200 pregnancies [1] [2] [3] . It is the second most common cause of abdominal pain in pregnant women after urinary tract infection (UTI) [1] [2] [3] and is the commonest non-obstetric reason for admission to hospital during pregnancy. Within this group, 80-90% of pregnant women are in the 2nd or 3rd trimester of their pregnancy. Multiparous women are also more commonly affected [4] [5] [6] [7] . During pregnancy, there is physiologic

more »

... of the collecting systems, allowing for migration of renal stones into the ureter, leading to obstruction and/or pain. This could explain the reason for the observation that during pregnancy, stones are twice as likely to be found in the ureter than in the renal pelvis or calyxes. Physiological hydronephrosis caused by the enlarging uterus is present in 90% of pregnancies by the 3rd trimester [8] [9] [10] [11] . This can make it more difficult to diagnose intramural obstruction during pregnancy. However, hydronephrosis due to pregnancy does not usually extend below the pelvic brim, and hence dilatation below this level is more likely to be due to an intraluminal cause such as ureteric stones. Renal colic, infection and obstruction are a source of significant morbidity and potentially mortality to mother and child. The main risks are pre-term labour, which can occur in up to 40% of women [8] , pre-term delivery and premature rupture of membranes. Abstract Introduction: Our aim was to evaluate the clinical efficacy and safety of ureteroscopy as a primary treatment for pregnant women with symptomatic ureteric stones who have failed conservative management. Materials and Methods: A systematic review of the literature from January 1990 to June 2011 was performed, including all English language articles. Outcome measures were clinical efficacy, in terms of stone clearance and need for additional procedures, and safety in terms of complications. Results: A total of 239 abstracts were screened and 15 studies were identified reporting on 116 procedures. The surgical methods of stone management employed were stone extraction with basket only (n = 55, 47%), laser fragmentation (n = 27, 23%; holmium, n = 20, pulse dye, n = 7), impact lithotripsy (n = 21, 18%), ureteroscopic lithotripsy (n = 6, 5%) and a combination of methods (n = 6, 5%). A post-operative stent was inserted in 64 of 116 procedures (55%). Complete stone clearance was seen in 100 of the 116 procedures (86%). There were 2 major complications (1 ureteral perforation and 1 case of premature uterine contraction) and 7 minor complications (5 urinary tract infections and 2 cases of post-operative pain). Conclusion: This review suggests that stone clearance using ureteroscopy is a relatively safe option in pregnancy with a high success rate.