It is my premise that it is immoral for any human to procreate. The reason for this stems from one idea. Life has much suffering. This suffering has two aspects. One is inherent, meaning that it cannot be changed by circumstances one is born into or experiences, but every human in every culture must contend with. The inherent suffering includes 3 categories.
One category is survival. Anything to do with keeping oneself alive in a society (work, consumption, trade, production, hunting, gathering, etc..) is something which is a form of suffering that we all must deal with. We toil, struggle, go through small and large unpleasant annoyances to maintain ourselves. Next, is the category of boredom. We become bored when we are not engaged in some activity or thought, and we must find an arbitrary goal to keep us out of boredom. Because of our inherent need to escape boredom when we are in that feeling of voidedness we are usually not in it too long. Finally there is the entertainment, or ways we find to kill time to escape the boredom. These fleeting entertainments are temporary solutions to try to escape the boredom of human existence. It could be any arbitrary goal of making a new business, dancing around the tribal fire and making jewelry out of bone to meditating or reading a book. The fleeting entertainments we use to fill the voidedness of boredom is endless. For these three reasons we are inherently suffering.
Besides the inherent suffering there is the external sufferings we are born into and which we may or may not experience at some point in our lives. That is emotional trauma, physical trauma of some sort resulting in clashes with other people, clashes with mental illness, clashes with natural phenomena, clashes with disease, clashes with small anoyances of daily activity.
For all these reasons, our moral imperative should be to act in the best interests of the not yet born generations of humans, the potential humans if you will, and not "cast" them into the world by the act of procreation. By not procreating you are not creating sources for more suffering in the world. It is too late for those who already exist (suicide is a different matter as it deals with the subject of whether it is better to keep existing, this is about whether it is better to start an existence).
In a similar vein of the anti-procreation stance, a philosopher named David Benetar wrote a book titled "Better Never to Have Been: The Harm of Coming into Existence". Briefly paraphrasing his premise, he states that: the presense of pleasure is good and the presense of pain is bad. However, while the absence of pain is good, if a non-existent potential person is deprived of a non-existent pleasure, than that is not bad. In other words, a non-existent "potential being" will not be deprived of the good of existence as he doesn't exist to be deprived of it.
To understand more about what I'm saying or to see a little more about where I'm coming from. Please go to: condemnedtoexistence.blogspot- This site is more of a real essay on what the anti-procreation movement is all about. A second site is anti-procreationmovement.blogspot - this is more of a rant that is unedited, but has the same basic idea. Ok, feel free to criticise and critique my argument. It is philosophy afterall. But feel free to agree.