The unnamed woman posted the letter on Reddit - and it's an absolute must-read.
"I can't bring you here. Not like this"
Emotionally addressing the letter to her 'little thing', she writes:
I can feel you in there. I've got twice the appetite and half the energy. It breaks my heart that I don't feel the enchantment that I'm supposed to feel. I am both sorry and not sorry.
I am sorry that this is goodbye. I'm sad that I'll never get to meet you. You could have your father's eyes and my nose and we could make our own traditions, be a family. But, Little Thing, we will meet again. I promise that the next time I see that little blue plus, the next time you are in the same reality as me, I will be ready for you.
Little Thing, I want you to be happy. More than I want good things for myself, I want the best things for the future. That's why I can't be your mother right now. I am still growing myself. It wouldn't be fair to bring a new life into a world where I am still haunted by ghosts of the life I've lived. I want you to have all the things I didn't have when I was a child. I want you to be better than I ever was and more magnificent than I ever could be.
I can't do to you what was done to me: Plant a seed made of love and spontaneity into a garden, and hope that it will grow on only dreams. Love and spontaneity are beautiful, but they have little merit. And while I have plenty of dreams to go around, dreams are not an effective enough tool for you to build a better tomorrow.
I can't bring you here. Not like this.
I love you, Little Thing, and I wish the circumstances were different. I promise I will see you again, and next time, you can call me Mum.
The letter has received a mixed comments, with some people slamming the woman for choosing to have an abortion.
WATCH: WOMAN FILMS HERSELF HAVING AN ABORTION TO PROVE IT 'ISN'T SCARY'
However it also received a lot of support, with one woman writing: "I'm sorry that this is a decision you have to make and I know it must have been extremely difficult to do so, but I commend you for your grace and honesty with yourself. "
Another added: "I had an abortion at 17, which was 26 years ago. Now I have two beautiful children, and can totally relate to your sentiments. I could never have provided for a child at 17, and I don't regret my decision.
"Like you, I feel like I put motherhood on hold so that I could later be better equipped to be a good parent and provider."
It's an understatement to say that abortion is not a decision one takes lightly, nor is it one that is always easy. Even when it's the right choice, there's can be a lot of pain involved.
READ: MIRACLE BABY SURVIVES MISCARRIAGE AND ABORTION PILL
This letter is a staunch reminder to people that are anti-abortion that the women choosing to terminate their pregnancies are real people, with real thoughts and feelings and emotions.