Hadith: I was about to forbid sexual intercourse during the breastfeeding period until I considered that the Romans and the Persians do it without any harm done to their children thereby

عن جُذَامَةَ بنت وهب، أخت عكاشة، قالت: حَضَرْتُ رسول الله صلى الله عليه وسلم ، في أناس وهو يقول: «لقد هَمَمْتُ أن أنهى عن الْغِيلَةِ، فَنَظَرْتُ في الروم وفارس، فإذا هم يُغِيلُونَ أولادهم، فلا يضر أولادهم ذلك شيئا»، ثم سألوه عن الْعَزْلِ؟ فقال رسول الله صلى الله عليه وسلم : «ذلك الْوَأْدُ الخفي»، زاد عبيد الله في حديثه: عن المقرئ، وهي: {وَإِذَا الْمَوْءُودَةُ سُئِلَتْ}.
[صحيح] - [رواه مسلم]

Judhāmah bint Wahb, sister of ‘Ukkāshah, reported: I was there when the Messenger of Allah (may Allah's peace and blessings be upon him) said to some people: "I was about to forbid sexual intercourse during the breastfeeding period until I considered that the Romans and the Persians do it without any harm done to their children thereby." Then they asked him about coitus interruptus, so the Messenger of Allah (may Allah's peace and blessings be upon him) said: "That is the hidden Wa’d (burying children alive)." ‘Ubaydullāh added to his Hadīth, which he reported from Al-Muqri: "This refers to {And when the girl [who was] buried alive is asked.} [Sūrat At-Takwīr: 8]"
[Authentic hadith] - [Narrated by Muslim]

Explanation

This Hadīth shows that the Prophet (may Allah's peace and blessings be upon him) wanted to forbid having intimate relations with one's wife during the suckling period, for it was common among the Arabs that doing so would cause harm to the baby. However, he did not forbid it once he came to know for sure that some peoples, like the Persians and the Romans, reported that no harm was caused to their children on account of doing this. The Prophet (may Allah's peace and blessings be upon him) was asked about ejaculating outside the vagina. He likened this to a pre-Islamic practice, when the Arabs used to bury their girls alive. The difference between both practices is that the infanticide was done openly, yet coitus interruptus is done privately.