Ch. 39 Pt. 2 Anatomy and Physiology
What are the three phases are identified in the endometrial cycle?
1. Menstrual 2. Proliferative 3. Secretory
What are the names of the potential spaces in the peritoneal cavity?
1. Vesicouterine pouch/Anterior culdesac 2. Rectouterine puch/Posterior culdesac/Pouch of Douglas
Menstruation almost always occurs how many days after ovulation?
14
What days does the proliferative phase occur?
15-28
How many potential spaces are located in the peritoneal cavity that are formed by the caudal portion of parietal peritoneum?
2
The typical endometrial cycle is identified and described in how many phases?
3
How many months after conception and implantation occurs does the human chorionic gonadotropin (hCG) produced by the zygote cause the corpus luteum to persist and continue to secrete progesterone?
3 months
What do ovaries usually measure in menarchal women?
3cm x 2cm x 1cm
What two sources of blood supply the anterior vagina, cervix and posterior surface of the vagina?
A branch of the uterine artery supplies the anterior vagina and the cervix, the posterior surface of the vagina is supplied by a direct branch, vaginal artery, of the internal iliac artery.
What does the constriction of the spiral arterioles cause?
A decreased blood flow to the endometrium resulting in ischemia and shedding of the zona functionalis.
What is Tamoxifen?
A drug given to help prevent breast cancer. (anti-estrogen)
Around what age does the female's reproductive years begin and cease?
A female's reproductive years begin around 11-13 years of age at the onset of menses, and end around age 50 when the menses ceases.
A mature follicle is known as what?
A graafian follicle and is typically 2 cm in size right before ovulation.
What stage begins on the first day of menstrual bleeding and continues until ovulation on day 14?
A stage of the ovulatory cycle known as the follicular stage.
How thick is the endometrium of a post menopausal patient that is not on hormone replacement therapy?
A thickness less than 5mm
The endometrium in anovulatory patients usually appear as what?
A thin, echogenic line.
Definition of Menorrhagia
Abnormally heavy or long periods and is often associated with uterine fibroids, iud or hormone imbalances.
Definition of Oligomenorrhea
Abnormally short or light periods or periods that do not occur regularly. Often associated with polycystic ovarian syndrome (PCOS)
From the internal iliac artery, the uterine artery crosses _.
Above and anterior to the ureter, extending medially in the base of the broad ligament to the uterus at the level of the cervix.
What shape do ovaries resemble?
Almonds
What could be a cause of Amenorrhea?
Amenorrhea may result from a congenital vaginal or cervical infection, trauma, ovarian dysfunction or other endocrine disturbances that affect ovarian function such as pituitary disease.
What can the arcuate vessels often be identified as sonographically?
Anechoic tubular structures in the outer third of the myometrium.
Persistent menorrhagia can lead to _.
Anemia
Where is the vesicouterine (anterior culdesac) located?
Anterior to the fundus of the uterus between the urinary bladder and the uterus.
About how many oocytes does the average female ovary contain at the time of birth?
Approximately 200,000
How long is the average menstrual cycle?
Approximately 28 days in length, beginning with the first day of menstrual bleeding.
The branches that perforate the serosa anastomose extensively anteriorly and posteriorly within the myometrium forming what?
Arcuate vessels that encircle the uterus.
What is Mittelschmerz?
Being able to tell when you are ovulating because at mid cycle pain occurs on whatever side ovulation is ocurring.
What artery supplies blood to the uterus?
Blood is supplied to the uterus by the uterine artery, arising from the anterior branch of the internal iliac artery.
The central medulla is composed of connective tissue containing _,_,_, and _?
Blood, nerves, lymphatic vessels, and some smooth muscle at the region of hilum.
What are some causes of oligomenorrhea?
Can be caused by emotional and physical stress, chronic ilnesses, tumors that secrete estrogen, poor nutrition, eating disorders and heavy exercise.
How is the space of retzius identified?
Can be identified between anterior bladder wall and the pubic symphysis.
Ovaries consist of an outer layer or cortex, which surrounds the _.
Central Medulla
Definition of secondary amenorrhea
Cessation of uterine bleeding in those who have previously menstruated.
What is anastomosis?
Communication between vessels by collateral channels.
What is a potential problem that occurs in the space of retzius?
Contains subcutaneous fat, but a hematoma or abscess in this location may displace the urinary bladder posteriorly.
About what day does ovulation occur within the 28 day cycle?
Day 14
What days does the menstrual phase occur?
Days 1-5
What days does the proliferative phase occur?
Days 6-14
As the ovarian follicles grow they fill with fliud and secrete increasing amounts of what hormone?
Estrogen
What two hormones are produced by the ovary?
Estrogen, Progesterone
The secretion of what hormone by the anterior pituitary gland causes the ovarian follicles to develop during the first half of the menstrual cycle?
FSH (follicle stimulating hormone)
The LH surge is accompanied by a smaller _ surge.
FSH surge that triggers ovulation on day 14
Why are the potential spaces in the peritoneal cavity significant?
Fluid may accumulate or pathology may be present in these locations.
What levels typically increase rapidly 24-36 hours before ovulation resulting in a surge?
LH levels rise, resulting in a process known as the LH surge.
The creation of the corpus luteum is known as?
Luteinization and is stimulated by the LH surge.
Definition of primary amenorrhea
Menarchy is delayed beyond 18 years of age
What terms are used to describe abnormal menstruation?
Menorrhagia Polymenorrhea Dysmenorrhea Amenorrhea Primary Amenorrhea Secondary Amenorrhea
The uterine artery gives off many branches that perforate the serosa and carry blood to the _?
Myometrium
What do post meno patients on HRT or taking tamoxifen usually demonstrate?
Normal endometrial thickness up to 8mm
Although typically 5-8 pre-antral follicles will begin to develop, how many usually reach maturity each month?
One
How many eggs on average are released each month?
One
What is the releasing of an egg called?
Ovulation
Definition of dysmenorrhea
Painful periods, often associated with endometriosis or adenomyosis.
Many women who are in _ will experience menorrhagia due to hormone imbalances.
Perimenopause
Where do the ovaries usually lie?
Posterior to the uterus at the level of the cornua. Suspended from the posterior aspect of the broad ligaments in a fold of peritoneum called the mesovarium.
Where is the rectouterine pouch located?
Posterior to the uterus between the uterus and rectum.
What hormone does the corpus luteum immediately begin secreting?
Progesterone
Blood is supplied to the emdometrium by the_?
Radial arteries that radiate from the arcuate arteries within the myometrium.
Definition of amenorrhea
Refers to absence of menstruation.
What is the rupture of a follicle associated with in the posterior culdesac mid cycle?
Small amounts of fluid.
What supports the ovary medially?
Supported medially by the ovarian ligaments, originating bilaterally at the cornua of the uterus, and laterally by the suspensory (infundibulopelvic) ligament, extending from the infundibulum of the fallopian tube and ovary to the pelvic sidewall.
Where does the vasculority to the pelvic cavity come from?
The aorta to the common iliac arteries which then bifurcate into the external and internal iliac arteries. The internal iliac arteries extend into the pelvic cavity, along the posterior wall and provide multiple branches that perfuse the pelvic structures to include the urinary bladder, uterus, vagina, and rectum.
Definition of Menopause
The cessation of menses
During the luteal phase, the cells in the lining of the ruptured ovarian follicle begin to multiply and create what?
The corpus luteum or yellow body.
Definition of Ovulation
The explosive release of an ovum from the ruptured graafian follicle.
What do the external iliac arteries supply?
The external iliac arteries become the common femoral arteries that bring blood to supply the lower extremities.
What single, thin layer of cells surrounds the tunica albuginea?
The germinal epithelium
What part of the brain regulates the menstrual cycle?
The hypothalamus, and is dependent on the cyclic release of estrogen and progesterone from the ovaries.
What phase does the secretory phase at the endometrial cycle correspond to?
The luteal phase of the ovarian cycle.
What do the changes in the endometrium correlate with?
The ovulatroy cycles or the ovary.
The regeneration of the endometrium is called what?
The proliferative phase and it lasts until luteinization of the graafian follicle around ovulation.
What is the name of an additional area that is sonographically significant?
The retropubic space, also called the space of retzius.
The endometrial phase after ovulation is referred to as what?
The secretory phase and extends from approximately day 15 to the onset of menses.
As the follicles produce estrogen, the estrogen stimulates what?
The superficial layer of the endometrium to regenerate and grow.
Where do the ovarian artery and uterine artery anastomose?
The uterine artery is tortuous and spirals up the sides of the uterus within the broad ligament to the cornua, where it courses laterally to anastomose with the ovarian artery.
What artery does the ovarian artery anastomose with providing additional blood to the ovary?
The uterine artery.
What do the spiral arteries do during the regeneration of the endometrium after menses to traverse the endometrium and supply the zona functionalis?
They lengthen.
Where do all ova begin development during embryonic life and remain until the onset of menarche?
They remain suspended animation within a pre-antral follicle as an immature oocyte.
The endometrium characteristically appears hyperechoic with the appearance of the "___"
Three line sign
What can the LH surge be used for?
Timing ovulation.
Where are the ovaries located compared to the iliac vessels?
Usually located medial to external iliac vessels and anterior to the internal iliac vessels and ureters.
During menses it is not uncommon to see _ within the uterine cavity?
Varying levels of fluid and debris.
Straight arteries supply the _, while the stratum highly coiled spiral arteries supply the _
Zona Basalis, Zona functionalis.
The thickness of the endometrium _ with menstruation becoming a _ echogenic line during the early proliferative phase.
decreases, thin
Many women who are in _ will experience menorrhagia due to hormone imbalances
perimenopause
What two cycles do women have that work together and wouldn't work without the other?
1. Menstrual Cycle 2. Ovarian Cycle
What are steroidal hormones responsible for?
1. Producing and maintaining secondary gender characteristics. 2. Preparing the uterus for implantation of a fertilized ovum. 3. Development of the mammary glands in the female.
Right before ovulation what does the endometrium average?
6-10 mm and becomes isoechoic within the myometrium.
After ovulation, during the secretory phase the endometrium reaches its thickest dimension. What does it average?
7-14 mm, becomes echogenic, blurring the "three line" appearance.
How many days after ovulation does the corpus luteum degenerate, causing the progesterone levels to drop?
9-11
Hemorrhage or infection within the fluid may be related to _.
A ruptured cyst, ascites, a ruptured corpus luteum cyst, ectopic pregnancy or pelvic inflammatory disease (PID)
The release of GnRH by the hypothalamus triggers the pituitary gland to secrete which hormones?
Secretes varying levels of gonadotropins (primarily follicle stimulating hormone) FSH and LH (luteinizing hormone)
Blood from the _ is shed during menses.
Spiral arteries
The radial arteries extend through the myometrium to the base of the endometrium, where straight and spiral arteries branch off the radial arteries to supply what?
The Zona Basalis of the endometrium.
What phase is altered when a menstrual cycle is less than or greater than 28 days?
The follicular phase.
What hormone does the hypothalamus begin to release when a young girl reaches puberty?
The hypothalamus begins the pulsatile release of the gonadotropin releasing hormone (GnRH).
What is the process of ovulation regulated by?
The hypothalamus within the brain.
How do the ovarian veins differ in the course that they take?
The left ovarian vein drains into the left renal vein while the right ovarian vein drains directly into the inferior vena cava.
After ovulation, the ovary enters what phase?
The luteal phase. This phase begins with ovulation and is 14 days in length, doesn't usually vary in length.
Where does the primary blood supply to the ovaries come from?
The ovarian arteries, which arise from the lateral aspect of the abdominal aorta, below the renal arteries.
The menstrual phase of the endometrium coincides with the follicular phase of what cycle?
The ovarian cycle
What should the appearance of the endometrium correlate with?
The patient's menstrual status.
Definition of Premenarche
The physiologic status of prepuberty, the time before the onset of menses.
As the estrogen level in the blood rises with follicle development, the pituitary gland does what?
The pituitary gland is inhibited from further production of FSH and begins secreting luteinizing hormone (LH).
Where is it normal to observe a small accumulation of free fluid throughout the menstrual cycle, especially following ovulation?
The posterior culdesac, there are no sonographic means of confirming that the fluid is related to ovulation.
What happens with ovulation and luteinization of the graafian follicle?
The progesterone secreted by the ovary causes the spiral arteries and endometrial glands to enlarge. This prepares the endometrium for implantation should conception occur.
The mesnstrual phase begins with the declining progesterone levels causing what?
The spiral arterioles constrict.
Definition of Menarche
The state after reaching puberty in which menses occurs normally every 28 days.
What induces characteristic changes in the endometrium?
The varying levels of estrogen and progesterone throughout the course of the menstrual cycle.
What do the three echogenic lines seen in the proliferative endometrium represent?
The zona basalis anteriorly and posteriorly with the central line representing the uterine cavity.
As regeneration of the endometrium occurs during the proliferative phase, the endometrium _.
Thickens. It thickens to an average of 4-8 mm in the proliferative phase, when measured as a double-layer from anterior to posterior.
The cortex consists primarily of follicles in varying stages of development and is covered by a layer of dense connective tissue called the _?
Tunica Albuginea
How is the ovary attached to the posterior aspect of the broad ligament?
Via the mesovarium
Definition of Polymenorrhea
When the menstrual cycle occurs at intervals of less than 21 days.
