Female Reproductive Physiology Flashcards
Are there glands in the mucosa of the vagina?
No
What types of cells detect foreign pathogens in the vagina?
dendritic cells
What part of the female reproductive tract provides secretions for lubrication during intercourse?
Cervical mucosa
The epithelial cells of the vaginal wall releases large amounts of ___?
Glycogen
Why do the epithelial cells of the vaginal wall secrete large amounts of glycogen?
It is metabolised by resident bacteria (lactobacillus), producing lactic acid & H2O2 - decreasing the pH (acidic), making it toxic to foreign pathogens
What does the adventitia of the vagina connect to?
Surrounding structures such as the urethra and urinary bladder
What layers exist in the muscularis of the vagina?
Outer ongitudinal and inner circular layer
What is the vaginas blood supply?
Internal vaginal artery branching off the uterine artery
What is the name of the portion of the cervix that projects into the vagina?
Ectocervix
What is the opening of the ectocervix called?
External os
What is the other name for the cervical canal?
Endocervix
When is the cervix relaxed and cervical mucous thin and at a ten-fold increase in secretion? What hormone causes this?
Ovulation, Oestrogen
What hormone causes thick secretions and a firm cervix?
Progesterone
The transformational zone separates the endocervix and ectocervix. What type of epithelium are these structures?
Endo: Simple columnar
Ecto: Stratified keratinised squamous
What is the pap smear and what does it entail?
A cytodiagnostic test for the early detection of cervical cancer. Scrape surface epithelial cells from transitional zone of cervix mucosa, spread on glass slide and stain.
What is the name of the stain used for a pap smear?
Papanicolaou
What is this?
An abnormal pap smear
What is this?
A normal pap smear
Where is a fertilised ovum implanted?
Uterus
What is the blood source for the uterus?
Internal illiac branches to uterine artery that also supplies the cervix and vagina
What are the 3 layers of the uterus? Describe them.
Perimetrium: Outer serous membrane
Myometrium: Smooth muscle (x3/4), thick, contracts during delivery. Cervix: more rigid and less contractile than rest of uterus
Endometrium: Mucous membrane, simple tubular glands, leukocytes (7%).
What layer of the endometrium is hormone responsive?
Stratum functionalis
What is the epithelium of the uterus?
Simple columnar
What are the two outermost layers of the overy?
Visceral peritoneum then tunica albuginea
Is the cortex or the medulla of the ovary the functional part for reproduction?
Cortex
What is the medulla of the ovary composed of?
CT, blood vessels, glands, nerves and lymphatics
What is the rate of pulsatile release of GnRH during follicular phase in a female?
Every 60-90 minutes
How many viable gametes does a female produce from 1 primary cell?
1
When do germ cells arise and colonise gonadal ridges becoming oogonia?
Week 5-6
Until what month of gestation are oogonia multiplying via mitosis? How many eggs present at this stage?
5th month, 7 million eggs1
When do primordial follicles develop?
When oogonia are transformed into primary oocytes.
What stage of meiosis are Primary oocytes arrested in?
Prophase 1
How many oocytes are in the cortical region of the ovary at birth?
2 Million
How many oocytes are in the ovary at puberty?
400,000
Oogenesis:
One dominant is selected to continue meiosis 1 producing two haploid cells. What are the two cells produced?
The first polar body and the secondary oocyte.
Oogenesis:
What happens to the first polar body?
Released with ovulation, may undergo meiosis 2
What stage of meisosis is the secondary oocyte arrested at and when does it continue meiosis?
Arrested at metaphase 2 until penetration by a sperm.
What happens to a secondary oocyte when penetrated by a sperm?
Following penetration by a sperm the secondary oocyte quickly completes meiosis 2 resulting in the formation of 1 large ovum, and a second polar body
How long is a oocyte viable after ovulation?
12-24hrs
What does the antrum of a follicle contain?
Growth/regulatory factors, proteoglycans, hyaluronan
Describe the features of a primordil follicle.
In the cortex just beneath tunica albuginea.
One layer of squamous follicular cells surround the primary oocyte in prophase 1.
The nucleus of the oocyte is positioned off centre - it appears very light.
Basement membrane separating the follicle from surrounding interstitial tissue. 20um in diameter.
Describe the features of an Early Primary follicle.
Marks the onset of follicular maturation. Primary oocyte increases in size and accumulates organelles.
The follicle cells now form a cuboidal epithelium surrounding the oocyte. Their cytoplasm may have a granular appearance, and they are for this reason also called granulosa cells.
Zona Pellucida begins to form (ZP3 sperm binding).
Primary oocyte at prophase I.
Describe the features of a late priary follicle.
The zona pellucida (glycoproteins, sperm binding) becomes visible.
Multiple layers of granulosa cells.
Parenchymal cells of the ovary surrounding the growing follicle become organised in concentric sheaths, the theca cells.
Primary oocyte at prophase I. Oocyte 100um in diameter.
Describe the features of a secondary follicle.
Small fluid-filled spaces (antrum) become visible between the granulosa cells. Full of sugar, calcium, GH, IGF.1, hyaluronan and proteoglycans.
Thick multiple layers of granulosa cells.
The theca cells differentiate into a theca interna and theca externa.
Oocyte is 125um diameter.
Describe the features of a Mature graafian follicle.
Follicle up to 2cm big.
The antrums enlarge and fuse to form 1 follicular antrum. Secondary oocyte at metaphase 2.
The oocyte is surrounded by several layers (from inside out): zona pellucida, cells of corona radiata / cumulus oophorus (stalk), antrum, follicular wall: granulosa cells, basement membrane & theca cells.
What is a characteristic of a preovulatory follicle?
– oocyte and cumulus oophorus cells break off from follicular wall and freely floats in antrum
What causes the rupture of the follicle during ovulation?
increased volume of and pressure inside follicular fluid, enzymatic action, LH, prostaglandins, plasminogen and oxytocin action
What is the intermediate between follicle and corpus luteum?
Corpus Haemorrhagicum
What happens to the follicle immediately post-ovulation?
Formation of corpus haemorrhagicum, an intermediate form between follicle and corpus luteum
Invasion of theca cells and vessels inside the cavity – blood replaces follicular fluid
Increase luteinization of granulosa and theca cells
Significant process of structural and functional remodeling
What is luteinization?
cells stop dividing, hypertrophy, rich in mitochondria and sER, steady state release of progesterone and androgen.
What is happening to form the corpus luteum?
The wall of the follicle collapses into a folded structure.
Formation of large (granulosa- derived) and small (theca-derived) luteal cells – produce steroids.
Lots of SER - produce oxytocin, progesterone and oestrogens – 12days.
Massive luteal proliferation – almost filling the cavity, and angiogenesis
What occurs to the Corpus luteum if pregnancy is established?
If pregnancy is established, C.L remains active for 3- 4 months (fetus makes hCG).
What happens to the corpus luteum if pregnancy is not established?
If the oocyte is not fertilised corpus luteum degenerates into a corpus albicans - whitish scar tissue within the ovaries.
Degenerated cells filled with lipids White scar left after degeneration process with intercellular hayline materials
Disappears after several months – reabsorbed.
What is significant about secretion of anti-mullerian hormone in women?
Anti-Mullerian Hormone (AMH) is secreted by granulosa cells in developing follicles. The level of AMH in a woman’s blood is general indicator of ovarian reserve (primordial follicles)
What are some symptoms of PCOS?
Multiple follicular cysts in ovaries
Thickened tunica albuginea
Hyperestrogen secretion
Amenorrhea
What is physiologically occuring in a Polycustic ovary?
Multiple early antral follicles.
No dominant one selected to go through to ovulation.
Low FSH and constant high LH
Thecal cell defect in steroid biosynthesis
How long may it take a primary follicle to develop from a primordial follicle?
12 months
What cells produce inhiibin in the ovary?
Granulosa cells
What hormone turns follicle into CL?
LH
What causes CL to degenerate?
Low LH levels
What occurs to the endometrium during the menstrual phase, what days of the cycle is this?
Uterus sheds (bleeds) all but the deepest part of the endometrium when ovarian hormones are at their lowest levels and gonadotropins are on the rise. Ends as growing follicle starts to produce oestrogen.
What happens to the endometrial layer of the uterus during the proliferative phase?
Under the influence of increasing oestrogen levels the endometrium rebuilds itself, a new functional layer is produced which thickens and its glands enlarge and spiral arteries increase in number (ovulation ~day 14).
Day 6-14
What happens to the endometrial layer of th uterus during the secretory phase?
The endometrium prepares for implantation due to increasing levels of progesterone, uterine glands secrete glycogen. If implantation does not occur the lining will shed due to lack of hormonal support.
Days 15-28
What causes the stratum functionalis to slough off during menses?
It sloughs off as the spiral arteries remain in a constricted state in response to low levels of progesterone, depriving the functional layer of an adequate blood supply.
What happens the the epithelial cells and loose connecive tissue in the endometrium during the proliferative phase?
Epithelial cells sitting on basal layer and loose connective tissue form the tubular, spiral glands. The spiral arteries found in the loose connective tissue between the spiral glands nourish the functional layer.
What happens to the epithelial cells of the endometrium in response to progesterone?
Epithelial cells of the basal and functional layers undergo hypertrophy. As a result, the spiral glands become more elongated and more spiral. Consequently, the endometrial layer reaches its greatest thickness.
What is the source of hCG?
Trophoblasts
What are the metabolic effects of progesterone on:
Uterus:
Breasts:
Uterus: endometrium secretion and myometrium relaxation
Breast (with prolactin): alveolar growth, inhibition of milk secretion
What are the metabolic effects of progesterone on:
Vagina:
Cervix:
Vagina: proliferation and leukocyte infiltration
Cervix: thick and sticky secretion
What are the metabolic effects of progesterone on:
CNS:
increase body temperature after ovulation, inhibition of GnRH release
