A CARLTON mother's involvement in a world-first clinical trial at St George Hospital resulted in a shock diagnosis.
Nadia Yee's son, Jayden, 2, was found to have a benign kidney tumour the size of a grapefruit while his mother was taking part in a pre-eclampsia trial.
The trial is helping doctors examine the long-term effects of the serious pregnancy disorder.
At a routine check-up offered to participants, doctors noticed Jayden's swollen belly and ordered tests to rule out cancer.
Jayden ended up being admitted to the Sydney Children's Hospital at Randwick where it took surgeons three hours to remove the tumour.
Mrs Yee said it was the first time in 10 years that St George Hospital specialist paediatrician Joseph Khouri had seen a tumour of this type that was not cancerous.
"We are so very thankful for the study and Dr Khouri," she said.
"Presumably, the tumour would have kept growing had it not been detected and removed."
Pre-eclampsia is characterised by high maternal blood pressure, protein in the urine and severe fluid retention.
It can cause mothers to develop diabetes, heart attacks and stroke later in life, said chief investigator and obstetrician Associate Professor Gregory Davies.
Mrs Yee did not have pre-eclampsia during her pregnancy with Jayden, but Jayden had pulmonary hypertension at birth.
She is still involved in the trial, which aims to recruit 300 women who gave birth at St George with, or without, pre-eclampsia.
Pre-eclampsia occurs in about 10 per cent of births at St George Hospital.
It causes blood to flow to the placenta and become sluggish, which, in severe cases, can starve the baby of oxygen and nutrients.
Jayden is a typically bubbly toddler, and is doing very well health-wise.