Musannaf Ibn Abi Shayba 9:1793

Ismail ibn Ayyash narrated to us, from Abdullah ibn Uthman ibn Khuthaym, from Makhul, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "You must seek young women, and marry them, for they are sweeter in their mouths, better in their character, and more fertile in their wombs."