Normal Physiology of the Menstrual Cycle

Question 1

What are the three main physiological phases of the menstrual cycle?

Answer 1

Follicular phase
Ovulation
Luteal phase

Question 2

What happens during the follicular phase of the menstrual cycle?

Answer 2

Follicle stimulating hormone (FSH) released from pituitary gland under control of hypothalamus
Cluster of ovarian follicles recruited
1 follicle fully matures = dominant follicle
Other non-dominant follicles die away
Oestrogen produced by ovary > thickening of endometrium

Question 3

What happens during the luteal phase of the menstrual cycle?

Answer 3

Residual follicle becomes corpus luteum
Corpus luteum produces progesterone > primes endometrium in readiness for implantation of fertilised ovum
If ovum not fertilised > corpus luteum dies > fall in oestrogen and progesterone > lining of uterus sloughed off > menstruation