My wife has a problem of spotting blood a week before her actual menses starts. Can she perform Islamic duties like Salat, read Qur'an and fast during this time?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Since your wife has a normal menstruation period, then the drops of blood that she finds just before her menstruation period are not considered part of the menstruation itself and they have no influence on the validity of the prayer or the fasting. But if these drops do not stop for a period enough for her to make ablution and perform prayer, then her ruling becomes similar to that of a Mustahaadhah (i.e. a woman who has blood discharges outside her monthly periods). Therefore, she has to perform ablution for every prayer and pray no matter how much blood comes during that prayer. Her prayer then is valid.

For more benefit on the difference between monthly menses and bleeding outside the monthly menses, please refer to Fataawa 129256, 199375, 192925, 183343, 154565, and 145201.

For more benefit on Istihaadhah and irregular menses, please refer to Fataawa 345745, 380429, 362518, 145201, 326818, and 156775.

For more benefit on irregular menses and signs of end of menses, please refer to Fataawa 395488, 361450, 355546, 323464, and 231715.

Allah knows best.