All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu 'alyhi wa sallam, is His slave and Messenger. Shaykh Ibn 'Uthaymeen said: "If she previously did not see the white discharge, as some women do not get this, she should fast. However, if she did see the white discharge previously, then she should not fast until she sees it."Allaah Knows best. (Source: islam_web) Classified in Siyaam (Fasting) > Conditions of the Validity of Saum