Sitting ergonomics and work modifications taking into consideration your bulging abdomen and thus the need to stretch more. Poor sitting posture and environment plus the increased reach creates pressure on your lower back.

Start with daily walk , correct posture .

This is common .as your baby grows and week pass on. Weight is on your low back. Pain arise due to weak back muscle . As strain on them increases. Solution:- - maintain good posture - avoid sitting on lower surfaces - avoid bending forward - avoid lifing anything - REST. AND PROPER SLEEP POSTURE. - HOT WATER BAG FOMENTATION FOR 10 -15 MIN - APPLY LOCAL MOVE OR GEL FOR PAIN - AVOID PAIN KILLER  MEDICINE - consult your doctor  regarding can u start with some yoga/ physio  for your back muscle .