Four months pregnant Wioletta Roslan, 37, died after her parachute failed to open when she jumped from a height of 300 metres near Stechelberg in Switzerland.
Her boyfriend, who jumped at the same time, watched helplessly as she tried to open her parachute after jumping off the cliff, which she had leapt from many times.
Wioletta's mother, Halina Zaniewska-Pettersson, told Sky News her daughter's boyfriend, Aleksander Domalewski, had described his horror as he jumped alongside Wioletta.
"He told me that she desperately tried to get her parachute to open without success," she said.
"It did not open and in the last moment she realised she was not going to succeed. He told me that she had simply spread her arms and waited for the impact."
She added: "I was always terrified every time I knew that she was doing the sport again and I kept expecting the worst – when she said that she was going to do one last jump while pregnant I begged her not to go.
"But she always wanted to carry on. I couldn't force not to do it – she was old enough to make up her own mind about things.
"All that is left for me now memories but my daughter lived her life to the full – she was a true adventurer." Wioletta had travelled the world as a professional base jumper after taking up skydiving when she was 19.
In a documentary film Wioletta said: "I only feel alive when I jump. I find normal life boring. I know that death always flies with me but we only have a certain amount of time on the earth. When the sun goes down then it's game over whoever you are."