Yeater filed a paternity suit against Bieber last week, claiming that she became pregnant following a sexual encounter with the 'Mistletoe' singer in October 2010.
She previously insisted that she has proof that Bieber fathered her son, saying: "I have provided evidence to my attorneys and it'll show in court [and] prove that my allegations are true."
Yeater once again opened up about her decision to file the paternity suit, insisting to The Insider that her life could be in danger.
"I'm scared. I was very hesitant [to file the suit]. This is a very serious matter [and] it had to be brought to his attention - to everyone's [attention]," she said.
Yeater was also questioned about reports that she previously filed a paternity lawsuit against former boyfriend John Terranova.
The 20-year-old appeared shocked when asked about Terranova, replying: "No comment."
Yeater also said she understands that the press may find unpleasant stories from her past, but insisted that they will not detract from the truth of her accusations against Bieber.
"I have nothing to hide… Everyone has a past and has made mistakes. There's nothing wrong with that," she declared.
Bieber has announced that he will take a DNA paternity test when he returns to the US following a global promotional tour in the next two weeks.
> Justin Bieber DNA test will end Mariah Yeater allegations, says source
> Justin Bieber 'baby mother' Mariah Yeater charged with battery