I had this so bad starting at 17 weeks! I would look up nerve glides and found some helpful movements that really helped ease the pain for me in between being able to see the Chiro!
I second what Emma said - nerve flossing exercises has helped so much
Im a massage therapist, def try getting a prenatal massage, it’ll release the QL & piriformis muscle from constricting the sciatic nerve & Other nerves surrounding pelvic area, physical therapy to strengthen & chiro could help but massage might benefit more.