Final answer:
During the transition phase of labor, contractions become irregular and unpredictable. They become more frequent and powerful with time, reaching maximum intensity.
Step-by-step explanation:
During the transition phase of labor, contractions become irregular and unpredictable. True labor progresses in a positive feedback loop where uterine contractions stretch the cervix, causing it to dilate and efface. Cervical stretching induces reflexive uterine contractions that dilate and efface the cervix further. These contractions become more frequent and powerful with time, reaching maximum intensity during the transition phase of labor.