A radiation perspective for treating loin pain in pregnancy by double-pigtail stents

To review the risks of placing double-pigtail stents during pregnancy in women presenting with loin pain associated with hydronephrosis.

A consecutive series of women presenting with loin pain and hydronephrosis in pregnancy were treated with double-pigtail ureteric stents. A flexible cystoscope was used to identify the ureteric orifice and to pass a guidewire into the renal pelvis under fluoroscopic guidance. Stents were placed using the exchange technique over a stiff guidewire. Procedures were carried out under none or limited sedoanalgesia. Screening times and radiation dose were recorded. Data were collected for the average uterine radiation dose from a variety of radiological procedures. Previous publications were reviewed to determine the lethal, teratogenic and carcinogenic risk to the developing fetus from radiation exposure.

Seven patients referred with symptomatic hydronephrosis during pregnancy were treated. The screening time during placement was minimized. The mean (range) uterus (i.e. fetal) dose was 0.40 (0.03-0.79) mGy. Most radiological procedures involve uterine doses of < 20 mGy, far below the 100 mGy that may result in fetal damage during periods of maximum radiosensitivity.

Minimized radiation exposure from a range of uroradiological procedures in pregnant women has limited fetal risk. The use of fluoroscopy for symptomatic hydronephrosis during pregnancy allows ureteric stents to be placed safely and reliably. The average excess risk to the fetus from this procedure is 1 in 43 000 of cancer induction and 1 in 100 000 of heritable disease, i.e. very small when compared with the natural incidence. Pregnancy should not exclude the use of appropriate diagnostic radiation exposure and urologists may conduct appropriate diagnostic and therapeutic procedures, taking care to limit X-ray exposure without fear of risk to the developing fetus.