Hey people, Isambard is actually right, the Prophet did encourage us to have many children alhamdulillah.

There is, for example, the hadith of the Messenger encouraging us to have kids so that he can have the biggest ummah on the day of Judgement...

Isambard, if you are that worried, don't worry, any large number of kids being produced by Muslims is compensated by the lack of kids being produced by westerners.