To draw blood, a needle is inserted beneath the skin. Regardless of the amount of pain, infants will usually cry.
Update Date 5/14/2014
Updated by: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.