Foetal Ureteric Calculus Producing Hydronephrosis and Hydroureter.

Dilatation of foetal urinary collecting system is common. But cause of obstruction, if any, arise from soft tissues or developmental abnormalities of urinary tract or other paradox. A prenatal diagnosis of a 'calculus' inside ureter producing obstruction and ultimate back pressure changes in collecting system of a foetus is not reported so far. Other than inborn error of metabolism, what aetiological factors lead to this, are a matter of concern and great research. Here kidneys are not dysplastic. Amniotic fluid volume remains normal. Antenatal administration of calcium either orally or parenterally could be a contributory factor as it promotes nephrocalcinosis; and uretric calculus has it's origin in kidneys as believed. There is no maternal symptom related to this entity. Here we report a unique case of foetal ureterolithiasis producing hydroureter and hydronephrosis. © Federation of Obstetric & Gynecological Societies of India 2020.