TLDR :

Having assessed the potential landscape with a former plate, I have come to a conclusion that regardless of your personality, if her other dude knocks her up, she will attempt to lock you down as the BB to raise her kid if you have your shit together.

Body:

Try this situation on for size. The girl cannot take any form of birth control pill or plan B, yet wants to ride the CC to the fullest. She is seeing you and who knows how many others.

You have your life together: decent salary, decent activities fulfilling your life, good family, good values, etc - a true catch. You are not a mess of a human (read recklessly exciting) being like her other fuckboys: the busboy who goes to work high, the soldier (not talking about those who are serious career military) , or whatever (pick your flavor of douche).

So she is sleeping with all of you (yay, igloo brothers!) and magically she gets pregnant.

What is a girl to do? Busboy still lives at home and has no prospects, my soldier is going on deployment and has a do nothing college degree, that's not gonna work. Do I raise it myself!? I can't do that, this isn't my fault!

Suddenly she appears at your door. "We gotta talk". Guess what, boy, you're a dad :)!

See my point? Do not take it personally. It's not your fault and is not a reflection of your personality - you just have the tools and the means to fit her adventure.

Protect your assets. Truly think about what the future landscape with a plate might look like. Don't walk into a room you do not know how to walk out of.