Progesterone has been proposed to be protective to the central nervous system following injury. This study assessed progesterone supplementation in the setting of contusional spinal cord injury in male and female rats. Short-term (5 days of either 4 or 8 mg/kg progesterone) and long-term (14 days of either 8 or 16 mg/kg progesterone) therapy failed to show any significant alteration in locomotor functioning and injury morphometrics after 21 days. This study does not support progesterone as a potential therapeutic agent in spinal cord injury.