An American skier who suffered birth defects due to the Chernobyl nuclear disaster and spent her early life in orphanages said Wednesday she was “on cloud nine” after winning Winter Paralympic gold.

Oksana Masters was born in 1989 in what is now Ukraine, and was then part of the Soviet Union, three years after a reactor exploded at the Chernobyl plant, sparking the world’s worst nuclear disaster.

At birth she had six toes on each foot, five webbed fingers on each hand and no thumbs, and her left leg was six inches (15cm) shorter than her right.

Her family gave her up and she lived in three different orphanages until the age of seven, when she was adopted by an American woman and taken to the United States.

Due to the severity of her birth defects, doctors decided to amputate both her legs, and she also had multiple rounds of reconstructive surgery on her hands.

But despite her disabilities, Masters was determined to get involved in sports. As well as skiing, she also competes in rowing, biathlon and cycling.

On Wednesday she won her first Paralympic gold, in the 1.1km cross-country sprint skiing at the Pyeongchang Winter Paralympics.

“I feel like I’m on cloud nine right now, I’ve been chasing this gold medal for such a long time,” said the 28-year-old.

“This is the most amazing medal of my career.”

Athletes with leg impairments compete in specially adapted sledges in Paralympic skiing events.

Masters had already won a silver in biathlon and a bronze in long-distance cross-country skiing at the Pyeongchang Paralympics.

She also won silver and bronze medals at the 2014 Sochi Paralympics, and a bronze in rowing at the London 2012 Summer Paralympics.

Masters said she believed the dark days of her childhood had helped her become a champion athlete.

“I am so happy I have been able to channel all the things that I went through when I was younger and make them into something positive,” she said.

The Chernobyl nuclear disaster happened when a safety test went wrong, causing a huge explosion that sent clouds of radioactive materials floating over Europe.