Shaykh Ibn al Uthaymeen , may Allah have mercy upon him, was asked the following question:

Question:

What is your opinion on the ruling regarding wearing a ring on the index finger of the right and left hand for the women and the men?

Answer:

The ring is to be worn on the pinky/baby finger and the ring finger and the middle finger this is more perfective and better for the women and the men however if it were to be a custom (to the people) that the woman wear the rings upon all five fingers then it is okay (for them to do so).

Translated by

AbdulFattaah Bin Uthman
Abu Fajr