A bit of history from the beginnings of Islam:
After conquering the Banu Mustaliq tribe in A.D. 628, Muhammad’s men deemed it “necessary” to rape their captive women  (citing their wives’ absence and untended desires). However, they also wanted to sell these women for a profit, which posed complications, as copulating with them risked impregnating them. So they rationalized that ‘azl (coitus interruptus) would solve the problem and asked Muhammad. The prophet went one step further and offered a cosmic rationalization , dismissing coitus interruptus as unnecessary, “for every soul that is to be born up to the Day of Resurrection will be born” — that is, pullout or not, you cannot thwart Allah’s will, so don’t bother.
How convenient. Murder, pillage, rape -- it's all Allah-approved!