title: Initiation of labor.
mesh_terms: D000305:Adrenal Cortex Hormones / Q000502:physiology; D000818:Animals; D002395:Catecholamines / Q000378:metabolism; D004967:Estrogens / Q000502:physiology; D005260:Female; D005333:Fetus / Q000502:physiology; D006801:Humans; D007745:Labor Onset; D007743:Labor, Obstetric; D009215:Myometrium / Q000033:anatomy & histology / Q000502:physiology; D010121:Oxytocin / Q000378:metabolism; D011247:Pregnancy; D011374:Progesterone / Q000502:physiology; D011453:Prostaglandins / Q000378:metabolism; D011817:Rabbits; D012756:Sheep; D014667:Vasopressins / Q000502:physiology
chemical_list: D000305:Adrenal Cortex Hormones; D002395:Catecholamines; D004967:Estrogens; D011453:Prostaglandins; D014667:Vasopressins; D011374:Progesterone; D010121:Oxytocin