It was narrated from Al-Miqdad bin Al-Aswad that 'Ali told him to ask the Messenger of Allah ﷺ about a man who comes close to his wife and prostatic fluid comes out of him - what should he do? ('Ali said:

) For his daughter is married to me and I feel too shy to ask him. So I asked the Messenger of Allah ﷺ about that and he said: "If any one of you experiences that, let him sprinkle water on his private part and perform Wudu' as for Salah."

أَخْبَرَنَا عُتْبَةُ بْنُ عَبْدِ اللَّهِ الْمَرْوَزِيُّ، عَنْ مَالِكٍ، - وَهُوَ ابْنُ أَنَسٍ - عَنْ أَبِي النَّضْرِ، عَنْ سُلَيْمَانَ بْنِ يَسَارٍ، عَنِ الْمِقْدَادِ بْنِ الأَسْوَدِ، أَنَّ عَلِيًّا، أَمَرَهُ أَنْ يَسْأَلَ، رَسُولَ اللَّهِ ﷺ عَنِ الرَّجُلِ إِذَا دَنَا مِنْ أَهْلِهِ فَخَرَجَ مِنْهُ الْمَذْىُ مَاذَا عَلَيْهِ فَإِنَّ عِنْدِي ابْنَتَهُ وَأَنَا أَسْتَحِي أَنْ أَسَأَلَهُ فَسَأَلْتُ رَسُولَ اللَّهِ ﷺ عَنْ ذَلِكَ فَقَالَ " إِذَا وَجَدَ أَحَدُكُمْ ذَلِكَ فَلْيَنْضَحْ فَرْجَهُ وَيَتَوَضَّأْ وُضُوءَهُ لِلصَّلاَةِ " .