Ridiculous. As stated elsewhere, having kids is giving a part of your self to create a new independent self. It will teach you the hard way compassion, love to the other, etc. It is exactly the opposite of selfishness.
How the hell can you hold such a paradoxical statement?
editadd: There is a very strong anti-child line of thought in the US, I felt it in many occasions (on Lifehacker, for instance), and I think it is very strange, and dangerous. Is it because of a fashionable thinking that humans are too many? Is it a consequence of utilitarian morals? Honest question here: I think it is a subject of tremendous importance. Hidden behind this apparently innocuous sentence and pushing its logic to its limits, one may find the death of humanism and the end of civilisation.
I think in this case, the paradox unravels if you realize that I precisely chose the words "having a child" instead of "raising a child."
The decision to mate is usually selfish, and the decision to spawn offspring is also selfish (except where it's careless). People don't have sex because it's their duty. People don't try to conceive a child because they feel responsible to anyone but themselves. They decide they want the experience of raising a child, and so they do it for themselves. The experience itself is, obviously, a mixture of selflessness and selfishness.
Also, the word "selfish" has slightly more negative connotations than I would prefer, but I can't think of any suitable words that wouldn't require a whole paragraph to qualify.