nor plant

i have norplant (5years)i mean the one that is use for 5 years, but three years later i went to my doctor that i wanted to remove it cause it causeing pain in my arms, so he remove the 4 rods and it remain 1. can that 1 prevent me from getting pregnant? or i need to have all the 5 rods to make it work? now i want to get pregnat but my doctor still push my appointment date to remve the last 1. can i still get pregnant with the one rod in my arm?