Your religion can allow you to do or avoid doing actions that affect you, and only you. It cannot allow you to do actions that affect others. Otherwise anyone who decides that their religion allows them to do things that significantly affect others, no matter how dangerous these things may be for others, will find a moral justification for it.
People do and have done horrible things throughout history because they decided their religion says it is okay, or even because they decided that it commands them to do so. Of course, that didn’t make any of these horrors really okay.
Even religious people think that actions that harm others or endanger others are not morally permissible in spite of the perpetrators’ attempts to justify them on religious grounds. So you don’t have to be an atheist in order to be anti-natalist. It is enough to understand that the line is where others are affected.
And reproduction does affect others.
In fact reproduction is much more than an affecting others, it is a decision for others that they will exist in the first place and to a very large extent an influence on what kind of existence they will have. Reproduction is at the very least affecting and in many cases a decision for others about the most significant components of their existence. For example, their genetic load, to what period they will be born, in what environment, in what society, with what cultural heritage, with which body, with which personality tendencies, where they will live, what events will occur in their lives at the most critical ages and with the most impact on the rest of their lives, etc. This is not only affecting others, it is to a large extent actually creating others and forcing others to be affected by all the conditions of their creation that were chosen not by them but by those who chose to create them. Creating people is forcing others to be who they are, the way they are, when they are, where they are.
Creating people is also forcing others to be harmed, be disappointed, get sick, be afraid, degenerate, and someday die.
Deciding that people are allowed to embrace whatever religion they choose according to their view and therefore make decisions about their own life is one thing. But it is a completely different thing to decide that people are allowed, according to their religion, to make such a rough and invasive intervention in the lives of others.
If your religion says it’s okay for you to impose something on someone else, that it’s okay for you to decide something for someone without them asking, expressing any desire for it, any interest, or agreeing to it, either you don’t understand your religion correctly or your religion doesn’t understand what it means for something to be right (morally).