Islam is the religion of bashfulness and modesty. It always seeks, through its teachings, the purification of hearts and the preservation of human dignity. Therefore, unlike the culture of nudity and pornography that has widely contaminated people’s minds and behaviors, Islam prohibits its followers from even speaking about their lawful marital intimate relations. Even in privacy a Muslim should observe shyness and fear from Allah.
Answering the question, Zienab Mostafa, a prominent Muslim scholar and preacher, said,
Privacy in intimate relations between a husband and wife is not merely in place but also, from the moral perspective, is in speech with strangers as well.
Intimate relations are supposed to be practiced within boundaries that would preserve the honor and dignity of the husband and wife, and keep them away from any intruders. That is why they should be practiced in a closed place where the couple would feel that their privacy will not be violated.