This excerpt is taken from the book "500 Questions and Answers for Women" based on the Fatwas of the Scholars of the Haramain, translated by Hafiz Abdullah Saleem.
و بالله التوفيق
(And success is from Allah)
— Saudi Fatwa Committee
❀ Question:
What is the ruling in Islamic law regarding a man who, while enjoying intimacy with his wife, suckles milk from her breast? Is such an act considered haram (forbidden) or makruh (discouraged)? And if the wife's milk enters the husband's stomach during this act, does this result in her becoming unlawful (haram) for him and make separation obligatory? Kindly inform us of the Islamic ruling. May Allah reward you.❀ Answer:
It is permissible for a husband to suck his wife's breast, and the milk entering the stomach does not establish a relationship of prohibition (raḍā‘ah).و بالله التوفيق
(And success is from Allah)
— Saudi Fatwa Committee