Female Reproductive Physiology

Question 1

The ovaries contain the ovarian ________, which in a cyclical fashion undergo _______ and release a mature egg every menstrual cycle

Answer 1

follicles

oogenesis

Question 2

what is oogenesis?

Answer 2

production of an egg

Question 3

Egg implants into the ______

Answer 3

uterus

Question 4

what are the 2 parts of the uterus?

Answer 4

Uterus has 2 parts which are the body and the cervix

Question 5

what are the different areas of a ovary?

Answer 5

surface

cortex

medulla

Question 6

what is the structure of the surface of an ovary?

Answer 6

connective tissue capsule covered with a layer of simple cuboidal epithelium

Question 7

what is the structure of the cortex of a ovary?

Answer 7

peripheral part, connective tissue containing ovarian follicles (one oocyte surrounded by single layer of cells)

Question 8

what is the structure of a medulla of a ovary?

Answer 8

central part, connective tissue with blood cells

Question 9

1

Answer 9

medulla (contains neurovascular structures)

Question 10

2

Answer 10

cortex (contains ovarian follicles)

Question 11

3

Answer 11

cuboidal epithelium

Question 12

what is the function of the ovaries?

Answer 12

• Oocyte production:
• One mature egg per menstrual cycle, around 400 ovulated during entire reproductive lifespan
• Majority of eggs perish during the cycle
• Finite number, declines with increasing age
• Steroid hormone production:
• Oestrogen develops female secondary sexual characters
• Progesterone prepares endometrium for implantation
• 50% of testosterone produced by ovaries before menopause

Question 13

what is oogenesis?

Answer 13

differentiation of the ovum (egg cell) into a cell competent to further develop when fertilized

Question 14

what is the process of oogenesis?

Answer 14

• Primordial germ cell mitosis in foetal life only and primordial follicles arrested in the stage of first melotic division until puberty
• First melotic division complete and second division starts after puberty and leads to the release of one secondary oocyte in a menstrual cycle which is capable of fertilisation
• Second melotic division completes after fertilisation of oocyte with sperm

Question 15

what are the follicular development stages?

Answer 15

• Primordial follicles – primary oocyte arrested in first meiotic division surrounded by one layer of squamous pre-granulosa cells
• Primary follicle – oocyte surrounded by zona and cuboidal granulosa cells
• Secondary follicles – increased oocyte diameter and multiple layer of granulosa cells, resumption of first meiotic division
• Tertiary/graffian follicle – follicular fluid between the cells which coalesce to form antrum, completion of first meiotic division to form secondary oocyte and start of second meiotic division

Question 16

Pictures hsowing Chromosomal division during oogenesis

Answer 16

Question 17

Endocrine control of female reproductive axis – Hypo_______-_______-_______ axis

Answer 17

Hypothalamic-pituitary-ovarian axis

Question 18

• The function of the ovaries are controlled and coordinated by ________

Answer 18

hormones

Question 19

The function of the ovaries are controlled and coordinated by hormones

what hormones and where are they from?

Answer 19

Starts at the hypothalamus in the brain and this released GnRH (gonadotropin releasing hormone) which then acts on the anterior pituitary gland causing it to release FSH (follicle stimulating hormone) and LH (Luteinizing hormone)

Question 20

LH and FSH cause the ovaries to release what hormones?

Answer 20

LH and FSH cause the ovaries to release oestrogen and progesterone which are steroid hormones that act on the uterus to coordinate the menstrual cycle

Question 21

what feedback is present in the Hypothalamic-pituitary-ovarian axis?

Answer 21

• Negative feedback is important to keep the hormone levels stable to make sure the menstrual and ovarian cycles are coordinated within one month
• Oestrogen on days 12-14 causes positive feedback to help ovulation

Question 22

describe the ovarian cycle?

Answer 22

Due to the positive feedback of oestrogen there is a peak of LH which results in ovulation (release of egg)

Question 23

what are the different stages in the ovarian cycle?

Answer 23

the follicular phase and the luteal phase

Question 24

what happens in the follicular phase?

Answer 24

Only one dominant follicle will develop in the follicular phase

Question 25

what happens in the luteal phase?

Answer 25

Question 26

what are the effects of oestrogen and progesterone on the endometrium?

Answer 26

Oestrogen causes thickening of the endometrium and progesterone causes changes in the vasculature of the endometrium and also adds thickness Reaches max thickness at day 28 in time for pregnancy and if this doesn’t happen then it breaks down and hormones decrease

Question 27

Ovarian and menstrual cycle interplay: Oestrogen is dominant in the ________ phase and progesterone is dominant in the _____ phase

Answer 27

follicular luteal

Question 28

Summary picture: showing the ovarian and mestraul cycle all together

Answer 28

Question 29

Case Study – Female Reproductive Physiology what is Amenorrhoea?

Answer 29

no periods

Question 30

what is primary and seconday Amenorrhoea?

Answer 30

Primary – never had a period Secondary – stop to bleed for 6 months or more sometime in their lives

Question 31

what causes Amenorrhoea

Answer 31

- Problem with regulating hormones - Problem with ovarian function - Problem with uterus or outflow tract

Question 32

Amenorrhoea can be cause by problems with regulating hormones, what things would cause this? * Hypothalamic or pituitary cause – hypogonadotropic hypogonadism (low FSH, LH, high prolactin)

Answer 32

* Function – excessive weight loss or gain, over exercising, stress (once any of these are fixed periods will return) * Chronic medical conditions – diabetes, sarcoidosis, renal disease, TB * Intracranial space occupying lesion – prolactinoma, tumours, cysts * Infection or trauma – meningitis, intracranial bleed, Sheehans * Drugs – glucocorticoids, anabolic steroids, opiates * Genetic – Kallmanns syndrome

Question 33

Amenorrhoea can be cause by problem with ovarian functions, what things would cause this? Hypergonadotropic hypogonadism – high or normal FSH, LHJ

Answer 33

* Genetic – turners syndrome (46X), fragile X * Ageing – steep decline in ovarian function past 35 years * POI (primary ovarian insufficiency) or POF (primary ovarian failure) * Chronic illness – autoimmune diseases * Radiotherapy or chemotherapy * Infection – tuberculosis, mumps oophoritis (inflammation of ovary)

Question 34

Amenorrhoea can be cause by problems with uterus or outflow tract, this can be congenital or iatrogenic what are some congenital causes?

Answer 34

* Absent uterus, vagina – lack of Mullerian duct development (MRKH syndrome) * Transverse vaginal septum or imperforate hymen – Mullarian duct fail to canalise * Androgen insensitivity syndrome

Question 35

Amenorrhoea can be cause by problems with uterus or outflow tract, this can be congenital or iatrogenic what are some iatrogenic causes?

Answer 35

* Uterine adhesions or synechiae (asherman syndrome) * Radiotherapy – pelvic or cervical

Question 36

what is the management of amenorrhoea?

Answer 36

* Life style changes * Optimise control of medical illness * Stop drugs or switch to alternatives * Prolactinoma- medical treatment * Intracranial SOL- surgical treatment * Vaginal anomalies (septum or hymen)- surgical treatment * Uterine adhesions- surgical division hysteroscopic * Fertility preservation before radiotherapy and chemotherapy * Fertility treatment- IVF with own or donor eggs