A medical connector includes a body having a distal end, a proximal end, and a sidewall extending between the distal end and the proximal end, a helical thread extending radially outward from a surface of the sidewall and comprising a crest portion, flank portions, and a root portion with the flank portions connecting the root portion to the crest portion, and at least one micro-thread extending radially outward from the surface of the sidewall. At least a portion of the micro-thread is spaced apart from the helical thread.