Final answer:
Infection, maternal stress, and uterine abnormalities can stimulate preterm labor in a pregnant surgical patient by triggering uterine contractions. Hormonal changes and physical cervical stretching typically lead to labor through a positive feedback loop of oxytocin secretion.
Step-by-step explanation:
Factors that can stimulate preterm labor in the pregnant surgical patient include infection, maternal stress, and uterine abnormalities. These factors can provoke physiological responses that lead to uterine contractions. Infections can provoke an inflammatory response that may trigger contractions, stress may lead to the release of certain hormones that stimulate contractions, and uterine abnormalities may directly affect the physical environment of the uterus prompting labor. During normal labor, hormonal changes and physical stretching of the myometrium and cervix by the fetus lead to increasing uterine irritability and contractions serving to dilate the cervix and expel the newborn. Labor is regulated by a positive feedback loop involving the secretion of oxytocin, which enhances uterine contractile strength and prompts further hormone production.