What happens when the egg is not fertilized

Explanation-

Secondary oocytes remain viable after ovulation for 12 to 24 hours, if sperm is not present for fertilization, it gets disintegrated.
Corpus luteum formed has two weeks lifespan, it stops its activity of secretion, and finally starts disintegrating into corpus albicans.
As the level of hormones-progesterone, estrogen, and inhibin decreases, by a negative feedback mechanism, the level of GnRH, LH, and FSH start rising.
The rising level of FSH, LH, and GnRH, resumes follicle growth and the new ovarian cycle starts.



Final Answer-

If the egg is not fertilized, the new ovarian cycle starts due to the rising level of hormones by a negative feedback system.