So in your case, the exact opposite happened. Women do different things for different reasons.
But if you had an inkling that it was your child, you should have persued it.
And sweetie, it's never too late to claim what's yours.
I did pursue it, I talked to lawyers, tried to make contact, appealed to the chick to do the right thing. At one point she basically (without coming out and saying it) admitted he was mine but it didnt matter, and since she had already talked to a lawyer she knew I was fucked. This is a lot more complicated than it seems, some of it gets lost because I'm actually typing this, if I were actually explaining it instead of typing you would see that its a far worse situation and that what this chick, and a lot of others do is really fucked up.
Also you have to understand this happened when I was a teen, so I didnt know shit at that point. Also, you have to understand that to pursue it, I not only have to pay for a lawyer, but possibly the Dna test. At the time that I was going at her hard to get her to fess up, I could barely make rent, much less lawyer and Dna. When I did have a meeting with a lawyer at the time, he told me he wouldnt advise me to pursue it, and gave me a plethora of reasons why not.
I think the real point is that woman need to be held accountable and be more responsible, and then we wouldnt have to worry about situations like this. If a woman sleeps with more than one man, gets pregnant and may not know who the father is, she needs to bite the bullet, accept her mistake and do the right thing. Just like if a man sleeps around and gets multiple chicks pregnant, theirs no excuse or sympathy for their promiscuity. It has to be balanced, if men being irresponsible as far as children are concerned is such a horrible thing(which it is), it shouldnt be looked on as any less when a female is at fault.
P.S. sorry for this long winded, Colin Powell influenced response.