Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter CFTT / CFIT
Flight Crew Returned To Clearance; Flight Crew Took Evasive Action; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Became Reoriented
Human Factors
On our approach into MFR we had the field in sight and were cleared a visual approach. The Captain was pilot flying and used the VOR DME-C as a reference for the visual approach. We crossed BRKET at 10;000 ft and then began a descent down to the field. We had discussed this approach in the approach brief and how it can keep you high so as we descended; [the Captain] asked for flaps 8 and 20 and then gear down to slow the plane down for a better descent. We were a few miles short of SERTE when we heard the EGPWS 'terrain pull up; pull up' alert and we immediately [executed] the escape procedure of disconnecting the autopilot; max thrust and leveling off the descent. The alert went away and we then continued the approach and landed on runway 32. I noticed we were around 8;200 ft as we leveled off which was a few hundred feet below the published altitude of 8;500 ft on the approach at SERTE.  As mentioned above; we had the field in sight and were cleared a visual approach however [the Captain] descended too aggressively which caused the warning. The cause was too steep of a descent on our approach which led to the 'terrain pull up' alert.Follow the published altitudes on an approach when using it as a reference in mountainous terrain to avoid alerts like we encountered. Even though we had the field in sight; the descent was still too aggressive and we should have followed the published altitudes on the approach since it was night time with all the surrounding terrain.
Air carrier First Officer reported responding to a GPWS terrain alert on a night visual approach to MFR.