A couples decision to have children is a personal choice. There are many factors that should be considered(financial, stability of relationship) before having them. Ideally, the conclusion to have kids is well thought out and both partners are on the same page. Most people realize having children is an awesome responsibility and huge commitment. If couples do not realize there are going to huge sacrifices, they are ill prepared for parenthood. A parent's job description presents itself as sacrificing on their own needs(sleep, finances, time) for their child's. This would not be construed as selfish act.

If you are deciding on having children for the to save a relationship or to change a partner's behavior, then this would be selfish. Ultimately, it comes down to motives and intent to determine weather or not it it is selfish. If a couple decides on not having children, and there motives are to sacrifice their joy of having children for the betterment of society(save resources), they are making a selfless decision.

Ultimately, it comes down to motives and intent. Determining if a couple is selfish or selfless cannot be viewed by the act alone.