Seyed Ali Shobayri, Seyed Ali Shobayri is of mixed Iranian and Scottish descent who found the path of the Ahlul Bayt (a) by his own research. He holds a BA in Islamic Studies from Middlesex University through the... Answered 1 year ago

Bismaillah, 

Asalamu Alaykom, 

It is permitted but if a woman was doing any particular act on her husband, then it is haram for her to consume any najasa.

Please read the following link which includes some ahadith and information on this matter: 

https://www.al-islam.org/islamic-marriage-handbook-syed-athar-husayn-sh-rizvi/sexual-techniques

May Allah grant you success