Sa'd bin Abu Waqqas (RA) reported that a person came to Allah's Messenger (ﷺ) and said: I do 'azl with my wife. Thereupon Allah's Messenger (ﷺ) said: Why do you do that? The person said: I fear harm to her child or her children. Thereupon Allah's Messenger (ﷺ) said: If that were harmful it would harm the Persians and the Greeks.