Question

Differentiate between the following:

Proliferative phase and Secretory phase

Answer 1

Basis of Difference	Proliferative phase	Secretory phase
Timing	The proliferative phase usually extends from about day 5 to day 14 of the menstrual cycle.	The secretory phase usually extends from about day 14 to day 28 of the menstrual cycle.
Other name	The proliferative phase coincides with the follicular phase of the ovarian cycle.	The secretory phase coincides with the luteal phase of the ovarian cycle.
Main pituitary influence	FSH from the anterior pituitary supports follicle development during this phase.	LH from the anterior pituitary supports ovulation and corpus luteum formation during this phase.
Ovarian events	A developing follicle matures into a Graafian follicle, and ovulation occurs at the end of this phase.	The ruptured Graafian follicle develops into the corpus luteum.
Endometrial changes	Oestrogen repairs and thickens the endometrium and increases its blood supply.	Progesterone further thickens the endometrium and stimulates secretion by its glands.
Outcome	This phase ends with the release of the secondary oocyte at ovulation.	If fertilisation does not occur, this phase ends with the breakdown of the endometrium and menstruation.