Consensus on the prenatal management of antenatally detected urological abnormalities

The incidence of an antenatally detected genitourinary abnormality is 0.5% of all pregnancies assessed, and rarely is antenatal intervention indicated. A survey of pediatric urologists was undertaken to evaluate current practice patterns and recommendations regarding the need to intervene in the antenatal period.

A survey instrument was mailed to all members of the Society for Fetal Urology. There were 7 case scenarios that addressed critical decision points in patients with antenatally detected genitourinary abnormalities.

A total of 112 of 188 Society for Fetal Urology members (60%) completed the survey. Observation with serial ultrasound was recommended for a 32-week fetus with ureteropelvic junction obstruction. For a 36-week fetus with suspected posterior urethral valves without oligohydramnios most respondents elected no intervention with a minority favoring early delivery. For a 23-week fetus with suspected posterior urethral valves and oligohydramnios with normal bladder electrolytes most respondents agreed with a vesicoamniotic shunt. There was no clear consensus for a 20-week fetus with suspected posterior urethral valves, oligohydramnios and a nonfunctioning right kidney. Most respondents recommended serial ultrasound to follow an 18-week fetus with suspected posterior urethral valves and normal amniotic fluid. Antenatal intervention was not recommended for a 20-week fetus with bilateral renal cystic disease, and most respondents elected no intervention for a 28-week fetus with a solitary kidney with suspected ureteropelvic junction obstruction and normal amniotic fluid.

Situations that warrant antenatal intervention for a genitourinary abnormality are exceedingly low and may include cases of oligohydramnios, suspected favorable renal function and the absence of life threatening congenital abnormalities. In cases with normal amniotic fluid antenatal intervention is not recommended regardless of the detected abnormality. There is an emerging trend toward early delivery of fetuses with severe genitourinary abnormalities, normal amniotic fluid and confirmed lung maturity.