Brief Answer:
Not Serious At This Stage. Additional Scan Must.

Detailed Answer:
Hello,

Thanks for writing to us.

It is not serious at this stage with above measurement. However, follow up scan is mandatory for monitoring and evaluation. It will not affect the normal growth of the baby until it is more than 15 mm.

Mild fullness/ dilation on both renal pelvis is common finding in ultrasound scan after 20 weeks pregnancy. It is seen in 1% of growing fetus. Dilated renal pelvis is associated with retaining urine and it could be due to blockage or compression of the ureter. Slight developmental defect in early pregnancy may be a cause of the same. This may get better on its own sometimes.

However, mild renal pelvis dilation is a temporary problem at 20 weeks and it does not cause any difficulties in rest of the pregnancy or delivery. It becomes significantly worse if dilation is severe - greater than 15 mm or there is a defect detected in the kidneys.

With this condition, baby is prone to develop urinary infection after birth. Early diagnosis and treatment can eliminate this. Mostly needs short course antibiotic therapy. Surgical correction is required if it is dilated more than 15 mm or renal abnormality is detected after birth during congenital anomaly review.

In such situations to get better answers I suggest two tests for my patients to rule out associated abnormality - 1) TIFFA scan (Targeted Imaging For Fetal Anomaly) - it is done in 18-23 weeks. 2) Quadruple Marker. Kindly, consult with your obstetrician regarding this.

To summarize, baby has high chance of being normal after birth with mild fullness of bilateral renal pelvis.

Hope, above information is quite helpful to you. Let me know if you need any clarification.

Wish your good health and successful motherhood.

Regards,
Dr Soumen

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