Do continuous yellow discharges during the period of purity necessitate istinja' (cleansing) and wudu' (ablution) for every prayer? Is istinja' performed before the prayer time sufficient if there is hardship and obsessive doubt? And what is the ruling on past prayers for which istinja' was not performed?

Everything that exits from the private parts (urinary or anal) invalidates ablution (wudu’). Vaginal discharges are pure but invalidate ablution. As for yellowish and brownish discharges (ṣufra and kudra), they invalidate ablution and are impure. It is obligatory to perform istinjā’ (washing after relieving oneself) from them and to purify any clothing and body parts they have touched.

Whoever is afflicted with continuous yellowish discharge should perform ablution for each prayer after its time has begun, pray the obligatory and supererogatory prayers, and protect herself by fastening a cloth. She is not required to re-tie the cloth every time she performs ablution. The more cautious opinion is that of the majority of scholars. As for past prayers, there is no need to make them up if the yellowish discharge was due to ignorance of its impurity. However, if she prayed without ablution from the yellowish discharge, thinking it does not invalidate ablution, then it is more cautious to make up these prayers. One must beware of obsessive doubts (wasāwis).