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Fetal Hydronephrosis

Fetal hydronephrosis, or kidney swelling, occurs when too much urine backs up into an unborn baby’s kidneys. 

Fetal Hydronephrosis Treatment: Why Choose Us?

The maternal-fetal medicine specialists at the Fetal Care Center excel at caring for women whose unborn babies are at risk for health complications from fetal hydronephrosis. After delivery, pediatric urologists and nephrologists (kidney specialists) at St. Louis Children’s Hospital provide specialized care for your baby.

About Fetal Hydronephrosis

Fetal hydronephrosis is one of the most common problems detected by prenatal ultrasounds. It affects approximately 1 out of every 100 newborns.

Uretral Obstruction diagram

Unborn babies with fetal hydronephrosis do not typically experience problems in the womb. In half of all cases, the condition resolves on its own by the third trimester. If the condition persists, it usually improves after childbirth without treatment.

Causes of Fetal Hydronephrosis

Severe cases of fetal hydronephrosis tend to run in families. Our genetic counselors can help you understand your risk for fetal hydronephrosis in future pregnancies.

Potential causes of fetal hydronephrosis include:

  • Blockage or narrowing of the ureters, the tubes that carry urine from the kidneys to the bladder
  • Urinary reflux, which causes urine to flow backwards into the ureters

Diagnosing Fetal Hydronephrosis

We use advanced ultrasound technology to diagnose fetal hydronephrosis in unborn babies. Because we perform a high volume of specialized obstetrical and gynecological tests, our experts catch problems that others might miss. A maternal-fetal medicine specialist is always present during ultrasounds to explain your unborn baby’s condition and treatment options.

Learn more about high-risk pregnancy tests.

Treating Fetal Hydronephrosis

You undergo regular ultrasound screenings throughout your pregnancy to monitor your unborn baby’s kidneys and amniotic fluid levels. We recommend that you deliver at a hospital equipped to care for a high-risk pregnancy, such as the Women & Infants Center. 

After delivery, your baby may receive advanced medical care in our Level IV newborn intensive care unit (NICU). Our focus is on keeping mom and baby together, which is why our NICU is connected to labor and delivery. 

Pediatric urologists and nephrologists (kidney experts) at St. Louis Children’s Hospital care for babies born with fetal hydronephrosis. Your baby will have a kidney ultrasound in the first few weeks after birth to determine a possible cause for hydronephrosis. Your doctor also may test your baby for kidney or bladder infections and abnormal kidney function. Some children with abnormal kidney function need surgery. 

Our urology services program is the only one in the St. Louis metropolitan area offering robotic surgery for children with certain urinary tract disorders. This minimally invasive technique results in less pain and faster recovery.

Contact Us

To make an appointment with a Washington University fetal care specialist at the Women & Infants Center, call 855.925.0631.