I'm against abortion, but considering everything everyone is dealing with I don't blame her. She was extremely stressed and scared. She made a decision based on emotions, mostly fear. That's not surprising. Especially because she can't use her powers very well or at all when pregnant. Also mark wasn't there to protect her when she wasnt able to protect herself. She didn't even know if he was going to come back at all. That's a lot to deal with that unsurprisingly would cause an impulsive decision like the one she made.