We have been trying for six months but no luck till now. Should we go to see a fertility specialist?

If you have been trying randomly for the last 6 months, you can wait till a year before you go seek help. If you have been trying on the best days of the cycles, which can be identified by clearly slippery cervical mucus or a positive ovulation test kit, its time to visit the doctor. If you are very worried and its affecting you emotionally, pop into the doctor's to do some basis checks such as ultrasound scan or pap smear to eliminate any obvious issues. All the best!