Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: Egg production in the ovary is part of the menstrual cycle. The menstrual cycle is a series of changes in the reproductive system of mature females that repeats every month on average. These changes include the development of an egg and follicle in the ovary. Answer: menstrual cycle
A:
What is the name for a series of changes in the reproductive system of mature females that repeats every month on average?