Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates from the Prophet (peace and blessings be upon him), and he mentioned the hadith; in it is: "I have not seen anything deficient in intellect and religion, yet despite that they overpower a man of sense." A woman said: O Messenger of Allah (peace and blessings be upon him)! What is the deficiency of our intellect and religion? He (peace and blessings be upon him) said: "The deficiency of intellect is that the testimony of two women remains equal to that of one man; and refraining from prayer for several nights and leaving the fasts of Ramadan, this is the deficiency of religion."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20540