The first half of the menstrual cycle is characterized by follicle maturation and FSH, while the second half involves progesterone accumulation and uterine lining thickening for potential implantation.

“I think if you can just generally understand that the first half of the menstrual/ovulatory cycle is marked by the maturation of the follicles and FSH and that the second half is marked by the accumulation of progesterone and the thickening of the uterine lining should fertilization and implantation occur, I think that you will certainly understand the female reproductive cycle better than most people out there.”