Is it permissible for a husband to inform his mother or anyone else about the details of the marital relationship, especially concerning delayed pregnancy and menstruation? Does this constitute an infringement upon the wife's privacy and secrets, or is it considered a form of filial piety? What is the Islamic legal ruling on this matter?

It is forbidden for a husband and wife to disclose what transpires between them regarding matters of intimacy, based on the Prophet's (peace be upon him) saying: "Indeed, among the worst people in rank before Allah on the Day of Resurrection is a man who goes to his wife, and she goes to him, then he discloses her secret." As for mentioning sexual intercourse without details, it is disliked if there is no need, and permissible if there is a need or a benefit derived from it, such as a wife claiming her husband's inability.

Secrets are divided into three types: what the Sharia commanded to be kept secret (such as secrets of the marital relationship), what its owner requested to be kept secret (which is not permissible to disclose unless the recipient is not obligated to keep it secret), and what is inherently secret and one came to know it through association. Disclosing some light personal matters may be permissible, as happened with Aisha (may Allah be pleased with her) when she informed the Prophet (peace be upon him) that Safiyyah had menstruated. It is advisable for the wife to explain her desire for generality and not detail to her husband if he generally tends to preserve privacy.