This is becoming a big demographic problem in the West. Formerly the issue with declining birth rates was postponement of marriage and childbearing. Now, increasing numbers of adults never enter into a permanent relationship and have no children. Birthrates continue to plummet. Demographically, the West is in a death spiral and in Europe that means ever increasing percentages of Muslims in the population. The West won’t be conquered, it will go with a whimper.
A very big concern. Western Civilization has enough things to fight. We don't need a low birth rate. C'mon people, think the big picture and long term. We definitely won't survive if we don't reproduce!