Question about smoking weed before conceiving

I don't smoke weed very often, but I did smoke last weekend and my question is, if I conceive with THC in my system, will the baby be born with THC in it's system? I live in Arkansas and someone told me that the THC will stay in the baby's system and they supposedly drug test when the baby is born. I am freaking out because I don't want to go through a battle with DHS. Any advice? And be nice. Please.