Female Reproductive System (2) Flashcards
What is an overview of the ovarian hormones and cycles? (4)
- FSH–> follicle development
- Maturation of follicle–> increase in circulating estrogen
- High estrogen–> LH surge thus ovulation occurs
- Corpus luteum: increase circulating progesterone and estrogen
What are the three “metriums” in the cervix/uterus?
Mesometrium: part of parietal peritoneum/ broad ligament that covers the uterus
Myometrium: muscular layer, thick, most mass
Endometrium: mucosal/ inner layer, thin, highly vascularized
What are the two structures in the cervix? What is the purpose of the cervix depending on cycles?
Cervix with internal and external os : fibrous, no smooth muscle, elastic fibres (hard/tough)
Mucus prevents passage of bacteria into the vagins
During ovulation, mucus secretions become watery so the sperm can get through, but this leads to a moment of weakness for pathogens to enter as well
What is the anatomy of the uterus based on the three metrium layers and shape? What other structures are near the uterus? (5)
Highly variable dimensions (pear shaped) between ppl and throughout the month
Outer muscular myometrium: 3 layers of smooth muscles, 90% of the uterine mass, force needed for parturition and used for release of menses
Mesometrium: parietal peritoneum (mesentery) covering uterus
Endometrium: mucosa layer, 10% of mass, contains two layers, the basal (always there) and the functional layer (built every month)
Lots of uterine glands: opening into endometrial surface (lumen) extend to lamina propria (connective tissue)
What are the phases of the menstrual cycle, how long does it last? What happens to the endometrium during it?
3 phases: menstrual, proliferative, secretory
Lasts around 28 days, very variable
From menarche to menopause
Structure of endometrium (functional layer) changes throughout the cycle
Uterine glands and blood vessels (thickening and production of secretion)
What are the hormones that cause the menstrual cycle? (2)
Ovarian hormones secreted during ovarian cycle
Estrogen: induced proliferation of endometrium following menstruation
Progesterone: causes endometrium to become secretory and prepares it for implantation
What is the structure of the endometrium?
Simple columnar epithelium
Lamina propria
Mucosa
Stratum functionalis or basalis
Where does the blood supply to the uterus come from, and how does it leave?
Ovarian vessels (suspensory ligament from abdominal aorta, and drains into IVC)
Transverse ligament on either side comes from internal iliac vessels and drains into the IVC: uterine vessels and vaginal vessels
True or False: All vessels of the uterus can anastomose
TRUE
What is the blood supply to the endometrium like? (5) What are the two main ones and what do they supply? Where do they different arteries lie?
Uterine artery - arcuate artery- radial artery - straight artery - spiral artery
Uterine, arcuate, radial all lie in the myometrium
Straight and spiral are in the endometrium and are the most important.
Straight: supply stratum basalis
Spiral: supply stratum functionalis
Spiral arteries are shed and regrow each menstrual cycle (angiogenesis)
What happens to the straight and spiral arteries throughout the uterine cycle? What happens to them when the corpus luteum is degenerating?
Straight arteries: remain unchanged through uterine cycle
Spiral arteries: grow during proliferative phase, enlarge and mature due to progesterone during secretory phase
Degeneration of CL: loss of progesterone, spasm of smooth muscle in walls of spiral arteries, endometrium becomes ischemic, dies and is shed
What happens to the endometrium when the spiral arteries are intact? What about when they degenerate?
Increase size of gland and more functional layer, high vasculature due to estrogen/ progesterone, filling of it with mucus and nutrients
Spiral arteries degenerate causing death of everything it supplies and has made
What happens during the follicular phase of the uterine cycle? What ovarian cycle phase is this equivalent to? (5)
Equivalent to follicular phase
Estrogen increase in body (due to maturing follicles)
Primary and secondary follicles maturing and enlarging in ovaries
Endometrium: epithelial cells of glands multiply and spread across surface, which restores uterine epithelium after menses
By ovulation (day 14): functional layer is several mm thick and highly vascularized
What happens during the secretory uterine phase? What ovarian phase is this similar too? (6)
Equivalent to luteal phase
Endometrium: glands enlarge and accelerate their rate of secretions (mucus rich in lipids/ glycogen)
Spiral arteries elongate through functional layer
Combined estrogen and progesterone causes this phase
Begins at time of ovulation and persists as long as CL is intact (if oocyte fertilized, hCG is produced maintaining CL), prepares endometrium for potential zygote
Peak at 12 days after ovulation
What is involved in the menstrual phase of the uterine cycle, what causes it, how long does it last? (5)
Degeneration of the functional layer (14 days after ovulation) due to decrease in hormone levels
Arteries constrict, weakens arterial walls, reduces blood flow, glands and surrounding tissue begin to die
Arterial wall ruptures, blood cells and degenerative tissue break away from endometrium and enter uterine cavity
Menses: 1-7 days, variable
Estrogen increases again (from developing follicles)
Where does uterine pain come from? (3)
Uterine inflammation and contraction (both from myometrium and ischemic blood vessels in endometrium)
Sometimes can feel granulosa cells digesting the parietal peritoneum
What is the anatomy/ mucosal functions of the cervix? (6)
Cervical canal passes between uterus and vagina (internal and external os)
Columnar cells produce mucus: prevents vaginal bacteria from entering, impacts sperm motility, changes throughout the month, becomes watery during ovulation to allow sperm entry
Forms plug during pregnancy and dilates during childbirth (relaxin hormone from placenta)
What is the functions and anatomy of the vagina? (anatomy is 7, functions is 3)
Elastic and muscular tube, extremely variable in size
Smooth muscles form rugae
Moistened by cervical mucus
Extensive blood vessels and lymphatics
Resident bacteria causes acidic environment
Extends from cervix to vestibule of external genitalia
Both somatic and autonomic innervation
Functions: eliminate menses, organ of copulation, forms birth canal during parturition
What is the structure of the vaginal epithelium? (7)
Stratified squamous epithelium
Cells contain glycogen (feeds resident bacteria)
Desquamated cells serve as substrate for lactic acid producing bacteria
Lactic acid maintains low vaginal pH (no cervical bacteria)
Low pH prevents growth of pathogens
Impact on sperm
Thick lamina propria with large number of lymphocytes
What are the vaginal fornices around the cervix and their function?
Anterior fornix (vesicouterine pouch)
Posterior fornix (rectouterine pouch)
Lateral fornices on either side
Want ejaculation IN the fornices therefore sperm is close to uterus and does not have to remain in acidic environment for long
What is the overall name for the external genitalia? What are the main parts? (10)
Vulva
Labia majora: protective skin with hair, travels up and forms the mons pubis
Mons pubis: mount at pubis area, made by labia majora, has hair
Labia minora: hairless skin, more medial, inner lips, forms prepuce
Prepuce of clitoris: hood at top to protect clit, formed by L. minora
External urethral opening, vaginal opening, clitoris
Vestibule, ischial tuberosity, coccyx
What are the 6 anatomical structures both on the male and female external genitalia that are called the same thing?
External urethral opening
External anal sphincter
Prepuce
Glans of penis/clitoris
Perineal raphe
Body of penis/clitoris
What are the 2 male structures and 3 female anatomical structures that are different between external genitalia? List them in their corresponding order.
Female: labia minora, labia majora, vaginal orifice
Male: Raphe of penis, scrotum
Both the male and female external genitalia have the perineal raphe. What is different between the two?
Male: zips all the way up to prepuce
Female: stops because vestibule present (stops at labia minora)
What are the perineal muscle homologues between males and females? Are there any differences between them? (3)
External urethral sphincter: regulates urethral opening, urine continence, more “developed” in males because it only controls one opening and in females it controls two
Levator ani forms external anal sphincter
External anal sphincter: regulates anal opening, fecal continence
What are the external urethral muscle differences between males and females? (1)
Males: clear separation of muscles around urethra
Females: mixing of urethral and vaginal muscles
What are some erectile tissue homologues in males and females? (4)
Body of clitoris: 2 corpora cavernosa (no bulb)
Body of penis: 2 corpora cavernosa and corpus spongiosum
Females: greater vestibular gland (secretion lubricates vaginal canal, 2)
Males: bulbourethral gland, cleans urethra before ejaculation, 1
What are the perineal muscles? (2)
Bulbospongiosus: covering bulbs of vestibule and greater vestibular glands, females have 2 around vestibule and males have 1 around bulb
Ischiocavernosus: covering erectile tissue of corpora cavernosa, both male and female have 2
What is the para-urethral glands homologous to in males?
Prostate gland (Skene’s gland)
What is involved in the upper innervation of the female reproductive system? (2)
Sympathetic, T12-L2: vasoconstriction of blood vessels, contraction of smooth muscles, ejaculation
- sensory and pain felt in lower back and abdomen
Parasympathetic, S2-S4: vasodilation blood vessels, erection
- sensory and pain felt lower back and perineum
What is involved in lower innervation of this system? (2)
Somatic motor, pudendal nerve (S2-S4): sensory felt within vaginal walls and perineum
What are some changes that happen in pregnancy? (4)
Vertebral column and nerve compressions
Skeletal muscles and all ligaments stretch
Increase in anterior mass (shifts pelvis, tilt anterior, stretch everything)
3rd trimester: relaxin causes fibrous ligaments to relax
What happens to the uterus in pregnancy? (6)
Expansion: growing fetus, increased size and number of blood vessels (placenta)
From pear to watermelon sized
Stretched 5x normal size
Shape changes throughout gestation
Stretches ligaments attached to it
Late in pregnancy, see a drop which means that baby is in correct position for birth
What happens to the cervix (2) and vagina (1) during pregnancy?
Cervix: closes (mucus plug providing protective barrier), tissue softens during labour and delivery (will shorten and widen, dilate due to relaxin)
Vagina: elasticity increases
What happens to all body systems during pregnancy? (4)
Movement of organs (UP)
Posture changes (due to ligament stretch and increase in anterior weight)
Cardiac and respiratory input and output changes
Increase waste production (both by GI and urinary systems)
What happens to breast tissue during pregnancy? (4)
Increase in size (milk ducts and glandular tissue increase in size)
Areolas darken and widen (visual for infant)
Superficial vessels more visible due to stretch
Colostrum (milk filled with antibodies to protect fetus, in 2nd trimester for 3 days after delivery)
What is the purpose of mammary glands? (4)
Apocrine glands: shedding of apical cytoplasm without cell death
Secrete milk for nourishment of newborn
Proliferate extensively during pregnancy
Regulated by sexual and pituitary hormones
What is occurring in mammary glands when lactating in terms of stimulation and ejection of milk? (4)
Milk production stimulated by: primarily prolactin (pituitary gland) and estrogen/ progesterone
Milk ejection: stimulated by oxytocin (also helps reduce size of uterus via contractions), causes contraction of smooth muscle in walls of lactiferous ducts and sinuses
