She said that she already had kids that she was taking care of, and also stated that taking care of the twins she was carrying would be too much of a burden on her personally and financially.
And, she didn't do it via surgery, she did it via the "abortion pill".
You may be right but she didn't actually say she has kids. At the 2:00 point, she referred to "the other lives I'm taking care of and am responsible for." Probably kids but could mean almost anything like her staff at the office or her multiple partners.
As far killing the twins with a pill versus surgery, dead is dead.
She had a choice. She chose to conceive--to create life and she conceived twins. Then she killed, in her words, the "two beings".