Female Reproductive Physiology Flashcards
What is included in the female reproductive organs?
Uterus, ovary, fallopian tube, cervix and vagina
Describe the surface of the ovaries
Connective tissue capsule covered with layer of simple cuboidal epithelium
Describe the cortex of the ovaries
Peripheral part
Connective tissue containing ovarian follicles
Describe the medulla of the ovaries
Central part
Connective tissue with blood vessels
What is a ovarian follicle?
One oocyte surrounded by single layer of cells
What are the functions of the ovaries?
Oocyte production
Steroid hormone production
Describe oocyte production
One mature egg per menstrual cycle, 400 ovulated over entire reproductive lifespan
Majority of eggs perish during cycle
Finite number which declines with age
Describe steroid production by the ovaries
Oestrogen develops female secondary sexual characters
Progesterone prepares endometrium for pregnancy
50% of testosterone produced by ovaries before menopause
Describe oogenesis at birth
Primordial germ cell mitosis in foetal life
The primordial follicles are arrested in stage of first meiotic division at birth so no further development until sexual maturity
Describe oogenesis at puberty
First meiotic division is complete and second division starts after puberty which leads to release of one secondary oocyte in menstrual cycle
When is second meiotic division completed?
After fertilisation of oocyte with sperm
What are primordial follicles?
Primary oocyte arrested in first meiotic division surrounded by one layer of squamous pre granulosa cells
What is a primary follicle?
Oocyte surrounded by zona and cuboidal granulosa cells
Activated by puberty
What is a secondary follicle?
Increased oocyte diameter and multiple layer of granulosa cells
Resumption of first meiotic division
Wat is a tertiary/ Graffian follicle?
Follicular fluid between cells which coalesce to form antrum, completion of first meiotic division to form secondary oocyte and start second meiotic division
What are the 2 phases of follicular development stages?
Preantral phase - oogonia to secondary follicle
Antral phase - tertiary to preovulatory follicle
Describe a summary of oogenesis
Before birth - oogonium undergoes mitosis to primary oocyte
After puberty meiosis continues to secondary oocyte
Then ovulation and sperm entry causes meiosis to be completed and fertilisation
What does the hypothalamus secrete in the hypothalamic-pituitary-ovarian axis?
GnRH
What does the pituitary secrete in the hypothalamic-pituitary-ovarian axis?
FSH and LH
What does the ovaries secrete in the hypothalamic-pituitary-ovarian axis?
Oestrogen and progesterone
Where does oestrogen and progesterone work on?
Uterus
When are negative feedbacks in the hypothalamic-pituitary-ovarian axis seen?
Can happen most of the cycle
When hormone levels are too high
When are positive feedbacks in the hypothalamic-pituitary-ovarian axis seen?
Day 12-14
Cause the surge responsible for ovulation
Describe GnRH and LH secretion and events in the ovary during the ovarian cycle
LH has a surge due to positive feedback loop from oestrogen - results in ovulation
Rise in the hormones leads from egg to developing follicle to ovulation then corpus luteum if not fertilised
What is the result of increased oestrogen?
Surge in LH leading to ovulation
What is the follicular stage of the ovarian cycle?
FSH causes follicle to mature and produce oestrogen which inhibits the development of other follicles
What is the ovulation phase of the ovarian cycle?
LH surges causes ovulation so follicle ruptures and releases secondary oocyte
What is the luteal phase of the ovarian cycle?
Ruptured follicle forms a corpus luteum and secretes progesterone
What is the menstruation phase of the ovarian cycle?
From day 28 when corpus luteum degenerates and a new ovarian cycle can begin
Describe the follicular stage of the menstrual cycle
LH and FSH increase - follicle matures - oestrogen and progesterone increase
Spike in the LH and FSH as oestrogen is increased - ovulation
What hormone is most important in the follicular stage of the menstrual cycle?
Oestrogen
What hormone is most important in the luteal phase of the menstrual cycle?
Progesterone
What is the role of progesterone in the menstrual cycle?
Changes in the blood vessels within the lining of the womb and adds thickness
What happens when there is no fertilisation of the egg in the menstrual cycle?
Hormone levels drop which starts the bleeding and new menstrual cycle
What are the types of amenorrhoea?
Primary - never had a period
Secondary - had a period after going through puberty but stopped bleeding for 6 or more months
What are causes of amenorrhoea?
Problem with regulating hormones
Problem with ovarian function
Problem with uterus or outflow tract
What are causes of hypothalamic or pituitary cause - hypogonadotropic hypogonadism (low FSH, LH and high prolactin)?
Functional - weight loss/ gain, over exercising and stress
Chronic - diabetes, sarcoidosis, TB and renal
Intracranial space occupying lesion
Infection or trauma
Drugs - glucocorticoids, anabolic steroids and opiates
Genetic - Kallmann’s syndrome
What are causes of hypergonadotropic hypogonadism - high or normal FSH or LH?
Genetic - Turner’s, fragile X
Ageing
POI or POF
Autoimmune diseases
RT or chemo
Infection - TB, mumps
What are congenital causes for problems in the uterus?
Absent uterus or vagina (MRKH syndrome)
Transverse vaginal septum or imperforate hymen-Mullerian duct fail
Androgen insensitivity syndrome
What are iatrogenic causes for problems in the uterus?
Uterine adhesions or synechiae
RT - pelvic or cervical
What are the managements for amenorrhoea?
Life style, optimise control of medical illness, stop drugs, prolactinoma - medical treatment, surgery, surgical division hysteroscopic and fertility treatment
