Abdullah asked the Messenger of Allah ﷺ: What is lawful for me to do with my wife when she is menstruating? He replied: What is above the waist-wrapper is lawful for you. The narrator also mentioned (the lawfulness of) eating with a woman in menstruation, and he transmitted the tradition in full.  

أَنَّهُ سَأَلَ رَسُولَ اللَّهِ ﷺ مَا يَحِلُّ لِي مِنَ امْرَأَتِي وَهِيَ حَائِضٌ قَالَ لَكَ مَا فَوْقَ الإِزَارِ وَذَكَرَ مُؤَاكَلَةَ الْحَائِضِ أَيْضًا وَسَاقَ الْحَدِيثَ  

I asked the Messenger of Allah ﷺ: What is lawful for a man to do with his wife when she is menstruating? He replied: What is above the waist-wrapper, but it is better to abstain from it, too. Abu Dawud said: This (tradition) is not strong.  

سَأَلْتُ رَسُولَ اللَّهِ ﷺ عَمَّا يَحِلُّ لِلرَّجُلِ مِنَ امْرَأَتِهِ وَهِيَ حَائِضٌ قَالَ فَقَالَ مَا فَوْقَ الإِزَارِ وَالتَّعَفُّفُ عَنْ ذَلِكَ أَفْضَلُ