Puerperal fever is defined as a rise in temperature of 100.4°F (38°C) or higher that occurs within the first ten days after delivery, excluding the first 24 hours. Common causes include infections, retained products of conception, and maternal conditions, with endometritis being the most prevalent infection. Treatment typically involves broad-spectrum antibiotics, supportive care, and possibly surgery, while prevention focuses on maintaining cleanliness and managing risk factors during childbirth.