14. Menstrual phase
• The functional layer of the uterine wall is
sloughed off and discarded with the menstrual
flow which lasts 4-5 days
• Blood + endometrial tissue
• Eroded endometrium is thin
15. Proliferative phase
• Follicular phase, estrogenic: lasts about 9
days
• Coincides with the growth of ovarian follicles
and is controlled by estrogen secreted by
these follicles
• 2 to 3 fold increase in the thickness of the
endometrium
16. Cont:
• Phases of repair and proliferation
• Surface epithelium reforms and covers the
endometrium
• The gland increase in number and length
• The spiral arteries elongate
17. Luteal phase
• Secretory: lasts 13 days
• Coincides with the formation, functioning and
growth of corpus luteum
• Glands become wide, tortuous and saccular
• Endometrium thickens because of the
influence of progesterone and estrogen
18.
19. If fertilization does not occur
• Corpus luteum degenerates
• Decreased estrogen and progesterone
• Secretory endometrium enters an ischemic
phase
• Menstruation occurs
20. Ischemic phase
• Occurs when oocyte is not fertilized
• Spiral arteries constrict, giving the
endometrium a pale appearance
• Loss of 20-80 ml of blood
• Menstruation lasts 3-5 days