Now she is recovering - and sharing her story, but wishes to remain anonymous.
"I don't know him - I don't know who he is - I don't know why he did this to me," she said.
The attacker held the door of a northbound 3 train for the 23-year-old and then without saying anything, slashed her.
"I grabbed my face, and then I saw the pool of blood coming from my face. I got scared. I started to shake and I felt my baby moving. It felt like it was going to leave me - it was horrible," she said.
The 23-year-old said she got off the train after taking it one more stop to Franklin Ave. That is where she was met with police to get help.
She says throughout the train ride, a couple helped her stay calm and called 911.
"I'm, grateful for what they did. Other riders didn't do anything to help me. They were in shock because of how intense it was," she adds.
Doctors rushed her into the operating room to make sure her baby was okay. She received 23 stitches. As she recovers, she is left with questions about her safety.
"We should have more security on every avenue. There's hard-working people who mind their own business and it's not fair that something like this happens due to someone who is irresponsible," she says.
The soon-to-be mom says she will not be riding the train any time soon.
"I'm scared. I panic and think that something like this will happen again," she says.
However, there is one thing she says she is secure about.
"God will do justice because there's no reason why he had to do this to me or to anyone. No one deserves something like this," she said.
Eyewitness News is tracking crime and safety across New York City and in your neighborhood
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