Systems, devices and methods related to retractor systems that retract tissue to allow access to a surgical site are described. The retractor systems can include a first rotatable arm attachable to a first blade, a second rotatable arm attachable to a second blade and a third linearly translatable arm attachable to a third blade. An attachment mechanism that is attachable to a fourth blade can be removably coupled to a mount on the frame. The retractors systems can also include two blade systems whereby when the retractor is in a closed configuration, the two blades form an oval opening.