When teaching a group of adolescents about variations in the length of the menstrual cycle, the nurse understands that the underlying mechanism is due to variations in which of the following phases?

Menstrual phase Proliferative phaseSecretory phaseIschemic phase

Explanation.

Variations in the length of the menstrual cycle are due to variations in the proliferative phase. The menstrual, secretory and ischemic phases do not contribute to this variation.