Praying during Menstruation because of Shyness
Question

She prayed whilst menstruating because of shyness. What is the ruling on that and what expiation should she offer?
Praise be to Allah.An-Nawawi (may Allah have mercy on him) said: “The Ummah unanimously agreed that it is prohibited for a menstruating woman to pray , whether that is obligatory prayers or supererogatory.” (Al-Majmu`, 2/351) 
Shaykh Ibn `Uthaymin (may Allah have mercy on him) was asked about that and replied: 
“It is not permissible for a woman who is menstruating or bleeding following childbirth to pray , because the Prophet (peace and blessings of Allah be upon him) said concerning women: “Is it not the case that if a woman menstruates she does not pray or fast ?” 
The Muslims unanimously agreed that it is not permissible for a menstruating woman to fast , or for her to pray. Based on this, if a woman does that she has to repent to Allah and to seek His forgiveness for what she did.” (Fatawa Al-Mar’ah Al-Muslimah, 1/285)
And Allah knows best.