Reproductive Lecture 2 🦋🍬 Flashcards
Mature oocyte is released every
28 days
The female reproductive organs
Vagina
Uterus
Uterine (fallopian) tubes
Ovaries
Anteflexion or retroflexion?
About 20%
retroflexed uterus, which could cause some pain during menstruation or intercourse
The vagina
An elastic muscular 7.5-9.0 cm tube extending from the cervix to the exterior of the body
three main functions of The vagina
. passageway for the elimination of menstrual fluid.
. receives the penis during sexual intercourse, and holds spermatozoa before they pass into the uterus.
. forms the lower portion of the birth canal through which the fetus passes during delivery.
Predicting fetal growth
Fundal height
Top of the uterus to the pubic bone
Number of centrimetres is approximately the number of weeks gestation
Predicting fetal growth increased
with twins, breech birth, gestational diabetes
Predicting fetal growth decreased
for small for gestational age and intrauterine growth restriction
The uterus
Pathway for sperm transport
Provides mechanical protection, nutritional support, and waste removal for the developing embryo and fetus.
Contractions in the muscular wall (myometrium) of the uterus are important in ejecting the fetus at the time of birth.
Source of menstrual fluid
The uterus
The endometrium can be subdivided into:
. Inner functional zone (stratum functionalis), that contains most of the uterine glands.
.Outer basilar zone (stratum basalis; adjacent to the myometrium). The basilar zone attaches the endometrium to the myometrium.
The uterine (fallopian) tube
The uterine tube provides a rich, nutritive environment containing lipids and glycogen, for spermatozoa, oocyte and the developing embryo.
Fertilisation typically occurs
in the ampulla
The epithelium lining of the uterine tube has both
ciliated and nonciliated secretory columnar cells
The mucosa is surrounded by
concentric layers of smooth muscle
Transport along the tube involves a combination of both
ciliary movement and peristaltic contractions
Ectopic pregnancy
When the fertilised embryo is implanted in any tissue other than the uterine wall
Where do most ectopic pregnancies occur ?
Most ectopic pregnancies occur in the uterine tube (tubal pregnancy)
What are the risk factors for ectopic pregnancy’s
Smoking, advanced maternal age and prior tubal damage are risk factors
The Ovary is comprised of three distinct regions
1 Outer ovarian cortex containing the ovarian follicles
2 Central ovarian medulla consisting of ovarian stroma and steroid producing cells
3 Inner hilum (hilus) which acts as a point of entry for nerves and blood vessels
How is the Primordial follicle formed?
The oocyte once surrounded by follicular (granulosa) cells form the primordial follicle.
How is the Primary follicles formed ?
As the follicles grow, they are called primary or pre-antral follicles. Immature primary follicles consist of only one layer of granulosa cells.
How is the zona pellucida formed
The oocyte secretes glycoproteins, which form a translucent acellular layer (zona pellucida).
Condensation of ovarian stromal cells, known as
thecal cells
follicle development why do follicles get larger
In response to FSH, some follicles get larger producing many layers of granulosa cells surrounding the oocyte.
How are Secondary follicle made?
As granulosa cells proliferate they produce a viscous follicular fluid that coalesces to form a single follicular antrum. These are called secondary or antral follicles.
How is the corona radiata made?
The innermost layer of granulosa cells becomes firmly attached to the zona pellucida and is called the corona radiata
What is the cumulus oophorus
Mass of loosely associated granulosa cells is known as the cumulus oophorus
How did the theca interna, formed
The theca develops to become the inner glandular, highly vascular theca interna,
How did the theca externa, formed
theca interna. and the surrounding fibrous capsule, the theca externa.
Mature (Graafian or pre-ovulatory) follicle
As the follicular antrum grows,
t is connected to the rim of peripheral granulosa cells by
the oocyte becomes suspended in fluid
a thin stalk of cells.
Ovulation
When dose the follicle bulge out from the ovarian surface.?
The increasing size of the follicle and its position in the cortex of the ovarian stroma causes it to bulge out from the ovarian surface.
The follicle ruptures, carrying with it the oocyte and its…
surrounding mass of cumulus cells.
The oocyte is collected by….
cilia on the fimbria, which sweep the cumulus mass into the uterine tube.
Corpus Luteum
The antrum breaks down….
the basement membrane between the granulosa and thecal layers breaks down and blood vessels invade.
The granulosa cells form large lutein (yellow pigment) cells (Corpus luteum =
yellow body
Corpus Albicans
The whitish scar tissue remaining,
white body), is absorbed back into the stromal tissue of the ovary over weeks to months.
This hormone is produced by the chorion of the embryo beginning about 8 days after fertilisation.
human chorionic gonadotropin (hCG)
hormone detected by home pregnancy tests.
The presence of hCG in maternal blood or urine is an indicator of pregnancy
The average menstrual cycle is about
28 days
Two phases in the ovarian cycle
follicular phase (day 1 to ovulation) and luteal phase (ovulation to menstruation)
Three phases in the uterine/menstrual cycle
menstruation, proliferative and secretory
Variation in length of menstrual cycle
The length of the luteal phase is usually 14 days. Which length is variable
The length of the follicular phase is variable, and changes as a women ages.
The female reproductive tract has two main functions
Produce oocyte
Incubate embryo
High levels of oestrogen exert a positive feedback effect on the
hypothalamus and anterior pituitary, thereby increasing secretion of GnRH and LH.
