(the mother of the believers) Um Sulaim, the wife of Abu Talha, came to Messenger of Allah ﷺ and said, "O Messenger of Allah ﷺ! Verily Allah is not shy of (telling you) the truth. Is it necessary for a woman to take a bath after she has a wet dream (nocturnal sexual discharge)?" Messenger of Allah ﷺ replied, "Yes, if she notices a discharge."
أَنَّهَا قَالَتْ جَاءَتْ أُمُّ سُلَيْمٍ امْرَأَةُ أَبِي طَلْحَةَ إِلَى رَسُولِ اللَّهِ ﷺ فَقَالَتْ يَا رَسُولَ اللَّهِ إِنَّ اللَّهَ لاَ يَسْتَحْيِي مِنَ الْحَقِّ هَلْ عَلَى الْمَرْأَةِ مِنْ غُسْلٍ إِذَا هِيَ احْتَلَمَتْ فَقَالَ رَسُولُ اللَّهِ ﷺ نَعَمْ إِذَا رَأَتِ الْمَاءَ