Urolithiasis in pregnancy.

Urolithiasis is the most common cause of urological-related abdominal pain in pregnant women after urinary tract infection. The disease is not uncommon during pregnancy occurring in 1/200 to 1/2,000 women, which is not different from the incidence reported in the nonpregnant female population of reproductive age. During pregnancy, the frequency of stone localization is twice as higher in the ureter than in the renal pelvis or calyx, but there is no difference between the left and right kidney or ureter. Urinary stones during pregnancy are composed mainly of calcium phosphate (hydroxyapatite) in 74% of cases and calcium oxalate in the remaining 26% (Ross et al., Urol Res 36:99-102, 2008). In conclusion, urolithiasis during pregnancy can be serious, causing preterm labor in up to 40% of affected women. The pathogenesis, diagnosis, and management are analyzed.