Uterus, Uterine Tubes And Cervix Flashcards
What is the inner lining of the uterus called?
→ Endometrium
What is the body of the uterus called?
→ Myometrium
What do the uterine tubes end in?
→ Fimbriae
What increases the size of a newborns uterus?
→ Maternal steroids
eg estrogen
What does the myometrium growth depend on?
→ Estradiol
When does the myometrium grow rapidly?
→ During puberty
Where do uterine fibroids originate?
→ Myometrium
→Corpus of uterus undergoes greater increase in size than cervix
In what shape are myometrial fibres?
→ Spiral fibre
When does the endometrium thicken?
→ At puberty
What is a good bioassay of estradiol levels?
→ 7-16mm
What is the stromal matrix?
→ The smallest the endometrium can get
What does the stromal matrix look like after menstruation?
→ Small columnar cells with glandular extensions 2-3mm thick
What is the proliferative phase stimulated by?
→ Estradiol from the dominant follicle
What are the changes that occur in the proliferative phase?
→ Stromal cell division, ciliated surface
→ Glands expand and become tortuous and secrete hormones
small muscular contractions of the myometrium.
→small muscular contractions of the myometrium.
→ Increased vascularity and neoangiogenesis
When are progesterone receptors expressed?
→ when the endometrium gets to 4mm
When does the secretory phase start and why?
→ 2-3 days after ovulation
→ The gradual rise in progesterone causes a reduction in cell division
What are the changes that occur in the secretory phase?
→ Glands increase tortuosity and distend
→ Secretion of glycoproteins and lipids
→ oedema
→ increased vascular permeability
→ arterioles contract and grow tightly wound
What happens to the myometrium during the secretory phase?
→ Myometrial cells enlarge
→ movement is suppressed to prevent contractions
→ blood supply increases
What causes menstruation?
→ Falling levels of steroid from the corpus luteum
→uterine lining does not receive the progesterone, causing the spiral arteries constrict and the endometrial tissue to become ischemic.
Describe what happens during menstruation
1) Prostaglandin release causes constriction of the spiral arterioles
2) Hypoxia causes necrosis
3) Vessels then dilate and bleeding ensues
4) Proteolytic enzymes are released from the dying tissue
5) Outer layer of the endometrium is shed and 50% is lost in 24 ho
How long does bleeding last?
→ 4 days
What happens to the basal layer after menstruation?
→ It is covered by an extension of glandular epithelium
What are the three components of the mucosa?
→ secretory
→ columnar ciliated epithelial cell
→ non ciliated peg cell
What does the muscularis layer consist of?
→ inner circular and outer longitudinal layers
→ blood vessels and lymphatics
What is the serosa?
→ Outer layer of the uterine tubes
What do epithelial cells in the uterine tube express?
→ High numbers of estrogen receptors in proliferative phase.
What happens to epithelial cells in the uterine tube mid cycle?
→ They undergo differentiation and increase in height
When can the oocyte pass?
→ Mid cycle
What happens to the epithelial cells of the uterine tube when progesterone starts being produced?
→ The estrogen receptors are suppressed
→ They decrease in height
→ luteal/ secretory phase
What is the function of the cilia?
→ They beat which moves the egg forward along with muscle layer contractions in response to estrogen
How long does the egg remain in the tube for?
→ 5 days
Where does fertilisation occur?
→ in the ampulla
What does damage to the epithelial cells cause?
→ Pain
→ Infertility
→ Ectopic pregnancy
What are the two ways to investigate tube patency?
→ Laparoscopy
→ Hystero-Salpingo-contrast sonography
How is laparoscopy done?
→ A small incision is done on the anterior abdominal wall and a laparoscope is put through
→ Uterine cannula passes through and some blue dye is injected into the uterus
→ If you don’t see the dye the tube is block
How is a hystero-salpingo-contrast sonography done?
→ Cannula is put through the cervix and instead of dye an ultrasound opaque dye is injected
→ you ultrasound the abdomen and monitor the progress of the dye
What is endometriosis?
→ The cells of the endometrium escape from the uterus and get into the body
→ They implant in other places and still respond to progesterone and estrogen
What is the cervix?
→ Muscular structure which is capable of great expansion
How thick is the endocervical mucosa?
→ 3mm thick
What is the cervix lined with?
→ A single layer of columnar mucous cells containing numerous tubular mucous glands
→Spiral groves- some sperm can get lost in the grooves- allows slow release of sperm
What do the mucous glands in the cervix do?
→ empty viscous alkaline mucus into the lumen
→protects the sperm so that they remain mobile for longer
What is the mucus in the cervix for?
→ Protective barrier to infection
What is the ectocervix covered with?
→ Monokeratinized stratified squamous epithelium
After ovulation what happens to the cervical mucus?
→ Reduced secretion and viscous mucous (reduced water content).
→Glycoproteins now form mesh like structure: acts as barrier to sperm and microorganisms.
What does estrogen cause in the cervix?
→ Changes in vascularity and oedema
→ follicular phase
How does the mucus change to allow sperm through?
→ During early stages the glycoproteins form a mesh that the sperm can’t get through
→ mid-cycle
Glycoproteins then become aligned and form microscopic channels that sperm can swim through
What does progesterone do to the cervical secretions in luteal phase?
→ Reduced secretion and viscous mucus
→ Glycoproteins form a mesh structure
How long is the vaginal canal?
→ approximately 10cm long
How is infection prevented in the vagina?
→ Layers of epithelial cells shed constantly and flow downward with secretions
→ secretions are acidic and provide anti-microbial protection
Where are Bartholins glands located?
→ Slightly posterior and left and right of the opening to the vagina
What do Bartholins glands do?
→ Secrete mucus to lubricate the vagina
What are Bartholins glands homologous to?
→ Bulbourethral glands in males
What is the outer serous layer of the uterus called?
perimetrium
Describe the fibral layers of the myometrium
→Inner layer circular fibres.
→Middle layer figure of 8 or spiral fibres.
→Outer layer longitudinal fibres.
→Muscle can contract in all directions
Describe the stromal matrix after menstruation
→columnar cells with glandular extensions 2-3mm thick
glands are simple and straight.
Which layer remains in menstruation?
→basal layer
What the three layers if the uterine tube?
→mucosa
→muscularis
→serosa
From the fimbriae, what are the three parts of the uterine tube?
→ampullary(mucosal folds are more prominent)
→isthmus
→intramural
