Nephrolithiasis in pregnancy.

Nephrolithiasis is a rare but important condition in pregnant women. The most common presenting complaint is flank pain. Recurrent or persistent urinary tract infections may also be due to nephrolithiasis. Ultrasound is the first-line diagnostic study, but a limited intravenous pyelogram can be obtained when indicated. Spontaneous passage of the stone occurs in approximately two-thirds of patients.