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The Female Reproductive SystemThe Female Reproductive System

P A R T B

Female Reproductive AnatomyFemale Reproductive Anatomy

Ovaries are the primary female reproductive Ovaries are the primary female reproductive organsorgans Make female gametes (ova)Make female gametes (ova) Secrete female sex hormones (estrogen and Secrete female sex hormones (estrogen and

progesterone)progesterone) Accessory ducts include uterine tubes, Accessory ducts include uterine tubes,

uterus, and vaginauterus, and vagina Internal genitalia – ovaries and the internal Internal genitalia – ovaries and the internal

ductsducts External genitalia – external sex organsExternal genitalia – external sex organs

Female Reproductive AnatomyFemale Reproductive Anatomy

Figure 27.11

The OvariesThe Ovaries

Paired organs on each side of the uterus Paired organs on each side of the uterus held in place by several ligamentsheld in place by several ligaments Ovarian – anchors the ovary medially to the Ovarian – anchors the ovary medially to the

uterusuterus Suspensory – anchors the ovary laterally to Suspensory – anchors the ovary laterally to

the pelvic wallthe pelvic wall Mesovarium – suspends the ovary in between Mesovarium – suspends the ovary in between

Broad ligament – contains the suspensory Broad ligament – contains the suspensory ligament and the mesovariumligament and the mesovarium

The OvariesThe Ovaries

Figure 27.14a

OvariesOvaries

Blood supply – ovarian arteries and the Blood supply – ovarian arteries and the ovarian branch of the uterine arteryovarian branch of the uterine artery

They are surrounded by a fibrous tunica They are surrounded by a fibrous tunica albuginea, which is covered by a layer of albuginea, which is covered by a layer of epithelial cells called the germinal epithelial cells called the germinal epitheliumepithelium

Embedded in the ovary cortex are ovarian Embedded in the ovary cortex are ovarian folliclesfollicles

OvariesOvaries

Each follicle consists of an immature egg Each follicle consists of an immature egg called an oocytecalled an oocyte

Cells around the oocyte are called:Cells around the oocyte are called: Follicle cells (one cell layer thick) Follicle cells (one cell layer thick) Granulosa cells (when more than one layer is Granulosa cells (when more than one layer is

present)present)

OvariesOvaries

Primordial follicle – one layer of Primordial follicle – one layer of squamouslike follicle cells surrounds the squamouslike follicle cells surrounds the oocyteoocyte

Primary follicle – two or more layers of Primary follicle – two or more layers of cuboidal granulosa cells enclose the cuboidal granulosa cells enclose the oocyteoocyte

Secondary follicle – has a fluid-filled space Secondary follicle – has a fluid-filled space between granulosa cells that coalesces to between granulosa cells that coalesces to form a central antrumform a central antrum

OvariesOvaries

Graafian follicle – secondary follicle at its Graafian follicle – secondary follicle at its most mature stage that bulges from the most mature stage that bulges from the surface of the ovarysurface of the ovary

Ovulation – ejection of the oocyte from the Ovulation – ejection of the oocyte from the ripening follicleripening follicle

Corpus luteum – ruptured follicle after Corpus luteum – ruptured follicle after ovulationovulation

OvariesOvaries

Figure 27.12

Uterine Tubes (Fallopian Tubes) Uterine Tubes (Fallopian Tubes) and Oviductsand Oviducts

Receive the ovulated oocyte and provide a Receive the ovulated oocyte and provide a site for fertilizationsite for fertilization

Empty into the superolateral region of the Empty into the superolateral region of the uterus via the isthmusuterus via the isthmus

Expand distally around the ovary forming Expand distally around the ovary forming the ampullathe ampulla

The ampulla ends in the funnel-shaped, The ampulla ends in the funnel-shaped, ciliated infundibulum containing fingerlike ciliated infundibulum containing fingerlike projections called fimbriaeprojections called fimbriae

Uterine TubesUterine Tubes

The uterine tubes have no contact with the The uterine tubes have no contact with the ovaries and the ovulated oocyte is cast ovaries and the ovulated oocyte is cast into the peritoneal cavityinto the peritoneal cavity

Beating cilia on the fimbriae create Beating cilia on the fimbriae create currents to carry the oocyte into the currents to carry the oocyte into the uterine tubeuterine tube

The oocyte is carried toward the uterus by The oocyte is carried toward the uterus by peristalsis and ciliary actionperistalsis and ciliary action

Uterine TubesUterine Tubes

Nonciliated cells keep the oocyte and the Nonciliated cells keep the oocyte and the sperm nourished and moistsperm nourished and moist

Mesosalpinx – visceral peritoneum that Mesosalpinx – visceral peritoneum that supports the uterine tubessupports the uterine tubes

UterusUterus

Hollow, thick-walled organ located in the Hollow, thick-walled organ located in the pelvis anterior to the rectum and pelvis anterior to the rectum and posterosuperior to the bladderposterosuperior to the bladder

Body – major portion of the uterusBody – major portion of the uterus Fundus – rounded region superior to the Fundus – rounded region superior to the

entrance of the uterine tubesentrance of the uterine tubes Isthmus – narrowed region between the Isthmus – narrowed region between the

body and cervixbody and cervix

UterusUterus

Cervix – narrow neck which projects into Cervix – narrow neck which projects into the vagina inferiorlythe vagina inferiorly

Cervical canal – cavity of the cervix that Cervical canal – cavity of the cervix that communicates with:communicates with: The vagina via the external osThe vagina via the external os The uterine body via the internal osThe uterine body via the internal os

Cervical glands secrete mucus that covers Cervical glands secrete mucus that covers the external os and blocks sperm entry the external os and blocks sperm entry except during midcycleexcept during midcycle

Supports of the UterusSupports of the Uterus

Mesometrium – portion of the broad Mesometrium – portion of the broad ligament that supports the uterus laterallyligament that supports the uterus laterally

Lateral cervical ligaments – extend from Lateral cervical ligaments – extend from the cervix and superior part of the vagina the cervix and superior part of the vagina to the lateral walls of the pelvisto the lateral walls of the pelvis

Uterosacral ligaments – paired ligaments Uterosacral ligaments – paired ligaments that secure the uterus to the sacrumthat secure the uterus to the sacrum

Round ligaments – bind the anterior wall to Round ligaments – bind the anterior wall to the labia majorathe labia majora

Peritoneal PouchesPeritoneal Pouches

Several cul-de-sacs of peritoneum exist Several cul-de-sacs of peritoneum exist around the uterusaround the uterus Vesicouterine pouch – lies between the Vesicouterine pouch – lies between the

bladder and the uterusbladder and the uterus Rectouterine pouch – lies between the rectum Rectouterine pouch – lies between the rectum

and the uterusand the uterus

Uterine WallUterine Wall

Composed of three layersComposed of three layers Perimetrium – outermost serous layer; the Perimetrium – outermost serous layer; the

visceral peritoneumvisceral peritoneum Myometrium – middle layer; interlacing layers Myometrium – middle layer; interlacing layers

of smooth muscle of smooth muscle Endometrium – mucosal lining of the uterine Endometrium – mucosal lining of the uterine

cavitycavity

Uterine WallUterine Wall

Figure 27.15b

EndometriumEndometrium Has numerous uterine glands that change Has numerous uterine glands that change

in length as the endometrial thickness in length as the endometrial thickness changeschanges

Stratum functionalis:Stratum functionalis: Undergoes cyclic changes in response to Undergoes cyclic changes in response to

ovarian hormonesovarian hormones Is shed during menstruationIs shed during menstruation

Stratum basalis:Stratum basalis: Forms a new functionalis after menstruation Forms a new functionalis after menstruation

endsends Does not respond to ovarian hormonesDoes not respond to ovarian hormones

Uterine Vascular SupplyUterine Vascular Supply

Uterine arteries – arise from the internal Uterine arteries – arise from the internal iliacs, ascend the sides of the uterus and iliacs, ascend the sides of the uterus and send branches into the uterine wallsend branches into the uterine wall

Arcuate arteries – branches of the uterine Arcuate arteries – branches of the uterine arteries in the myometrium that give rise to arteries in the myometrium that give rise to radial branchesradial branches

Radial branches – descend into the Radial branches – descend into the endometrium and give off:endometrium and give off: Spiral arteries to the stratum functionalisSpiral arteries to the stratum functionalis Straight arteries to the stratum basalisStraight arteries to the stratum basalis

Uterine Vascular SupplyUterine Vascular Supply

Degeneration and regeneration of spiral Degeneration and regeneration of spiral arteries causes the functionalis to shed arteries causes the functionalis to shed during menstruationduring menstruation

Veins of the endometrium are thin-walled Veins of the endometrium are thin-walled with occasional sinusoidal enlargementswith occasional sinusoidal enlargements

VaginaVagina

Thin-walled tube lying between the Thin-walled tube lying between the bladder and the rectum, extending from bladder and the rectum, extending from the cervix to the exterior of the bodythe cervix to the exterior of the body

The urethra is embedded in the anterior The urethra is embedded in the anterior wallwall

Provides a passageway for birth, Provides a passageway for birth, menstrual flow, and is the organ of menstrual flow, and is the organ of copulationcopulation

VaginaVagina

Wall consists of three coats: fibroelastic Wall consists of three coats: fibroelastic adventitia, smooth muscle muscularis, and adventitia, smooth muscle muscularis, and a stratified squamous mucosa a stratified squamous mucosa

Mucosa near the vaginal orifice forms an Mucosa near the vaginal orifice forms an incomplete partition called the hymenincomplete partition called the hymen

Vaginal fornix – upper end of the vagina Vaginal fornix – upper end of the vagina surrounding the cervixsurrounding the cervix

VaginaVagina

Figure 27.16a

Female External Genitalia: Female External Genitalia: DeepDeep

Figure 27.16b

External Genitalia: Vulva External Genitalia: Vulva (Pudendum)(Pudendum)

Lies external to the vagina and includes the Lies external to the vagina and includes the mons pubis, labia, clitoris, and vestibular mons pubis, labia, clitoris, and vestibular structuresstructures

Mons pubis – round, fatty area overlying the Mons pubis – round, fatty area overlying the pubic symphysis pubic symphysis

Labia majora – elongated, hair-covered, fatty Labia majora – elongated, hair-covered, fatty skin folds homologous to the male scrotumskin folds homologous to the male scrotum

Labia minora – hair-free skin folds lying within Labia minora – hair-free skin folds lying within the labia majora; homologous to the ventral the labia majora; homologous to the ventral penispenis

External Genitalia: Vulva External Genitalia: Vulva (Pudendum)(Pudendum)

Greater vestibular glandsGreater vestibular glands Pea-size glands flanking the vagina Pea-size glands flanking the vagina Homologous to the bulbourethral glandsHomologous to the bulbourethral glands Keep the vestibule moist and lubricatedKeep the vestibule moist and lubricated

External Genitalia: Vulva External Genitalia: Vulva (Pudendum)(Pudendum)

Clitoris (homologous to the penis)Clitoris (homologous to the penis) Erectile tissue hooded by the prepuceErectile tissue hooded by the prepuce The exposed portion is called the glansThe exposed portion is called the glans

PerineumPerineum Diamond-shaped region between the pubic Diamond-shaped region between the pubic

arch and coccyx arch and coccyx Bordered by the ischial tuberosities laterallyBordered by the ischial tuberosities laterally

Mammary GlandsMammary Glands

Modified sweat glands consisting of 15-25 lobes Modified sweat glands consisting of 15-25 lobes that radiate around and open at the nipple that radiate around and open at the nipple

Areola – pigmented skin surrounding the nippleAreola – pigmented skin surrounding the nipple Suspensory ligaments attach the breast to Suspensory ligaments attach the breast to

underlying muscle fasciaunderlying muscle fascia Lobes contain glandular alveoli that produce milk Lobes contain glandular alveoli that produce milk

in lactating womenin lactating women Compound alveolar glands pass milk to Compound alveolar glands pass milk to

lactiferous ducts, which open to the outsidelactiferous ducts, which open to the outside

Structure of Lactating Mammary Structure of Lactating Mammary GlandsGlands

Figure 27.17

Breast CancerBreast Cancer Usually arises from the epithelial cells of the Usually arises from the epithelial cells of the

ductsducts Risk factors include:Risk factors include:

Early onset of menses or late menopauseEarly onset of menses or late menopause No pregnancies or the first pregnancy late in lifeNo pregnancies or the first pregnancy late in life Previous history of breast cancer or family history of Previous history of breast cancer or family history of

breast cancerbreast cancer Hereditary factors including mutations to the genes Hereditary factors including mutations to the genes

BRCA1 and BRCA2BRCA1 and BRCA2

70% of women with breast cancer have no 70% of women with breast cancer have no known risk factorsknown risk factors

Breast Cancer: Detection and Breast Cancer: Detection and TreatmentTreatment

Early detection is by self-examination and Early detection is by self-examination and mammographymammography

Treatment depends upon the Treatment depends upon the characteristics of the lesioncharacteristics of the lesion

Radiation, chemotherapy, and surgery Radiation, chemotherapy, and surgery followed by irradiation and chemotherapyfollowed by irradiation and chemotherapy

Today, lumpectomy is the surgery used Today, lumpectomy is the surgery used rather than radical mastectomy rather than radical mastectomy

OogenesisOogenesis

Production of female sex cells by meiosisProduction of female sex cells by meiosis In the fetal period, oogonia (2In the fetal period, oogonia (2nn ovarian ovarian

stem cells) multiply by mitosis and store stem cells) multiply by mitosis and store nutrientsnutrients

Primordial follicles appear as oogonia are Primordial follicles appear as oogonia are transformed into primary oocytestransformed into primary oocytes

Primary oocytes begin meiosis but stall in Primary oocytes begin meiosis but stall in prophase Iprophase I

Oogenesis: PubertyOogenesis: Puberty At puberty, one activated primary oocyte At puberty, one activated primary oocyte

produces two haploid cells produces two haploid cells The first polar bodyThe first polar body The secondary oocyteThe secondary oocyte

The secondary oocyte arrests in The secondary oocyte arrests in metaphase II and is ovulatedmetaphase II and is ovulated

If penetrated by sperm the second oocyte If penetrated by sperm the second oocyte completes meiosis II, yielding:completes meiosis II, yielding: One large ovum (the functional gamete)One large ovum (the functional gamete) A tiny second polar bodyA tiny second polar body

Figure 27.19

Ovarian CycleOvarian Cycle

Monthly series of events associated with Monthly series of events associated with the maturation of an eggthe maturation of an egg

Follicular phase – period of follicle growth Follicular phase – period of follicle growth (days 1–14)(days 1–14)

Luteal phase – period of corpus luteum Luteal phase – period of corpus luteum activity (days 14–28)activity (days 14–28)

Ovulation occurs midcycleOvulation occurs midcycle

Follicular PhaseFollicular Phase

The primordial follicle, directed by the The primordial follicle, directed by the oocyte, becomes a primary follicleoocyte, becomes a primary follicle

Primary follicle becomes a secondary Primary follicle becomes a secondary follicle follicle The theca folliculi and granulosa cells The theca folliculi and granulosa cells

cooperate to produce estrogenscooperate to produce estrogens The zona pellucida forms around the oocyteThe zona pellucida forms around the oocyte The antrum is formedThe antrum is formed

Follicular PhaseFollicular Phase

The secondary follicle becomes a The secondary follicle becomes a vesicular folliclevesicular follicle The antrum expands and isolates the oocyte The antrum expands and isolates the oocyte

and the corona radiataand the corona radiata The full size follicle (vesicular follicle) bulges The full size follicle (vesicular follicle) bulges

from the external surface of the ovaryfrom the external surface of the ovary The primary oocyte completes meiosis I, and The primary oocyte completes meiosis I, and

the stage is set for ovulationthe stage is set for ovulation

Ovarian CycleOvarian Cycle

Figure 27.20

OvulationOvulation

Ovulation occurs when the ovary wall Ovulation occurs when the ovary wall ruptures and expels the secondary oocyteruptures and expels the secondary oocyte

Mittelschmerz – a twinge of pain Mittelschmerz – a twinge of pain sometimes felt at ovulationsometimes felt at ovulation

1-2% of ovulations release more than one 1-2% of ovulations release more than one secondary oocyte, which if fertilized, secondary oocyte, which if fertilized, results in fraternal twins results in fraternal twins

Luteal PhaseLuteal Phase After ovulation, the ruptured follicle collapses, After ovulation, the ruptured follicle collapses,

granulosa cells enlarge, and along with internal granulosa cells enlarge, and along with internal thecal cells, form the corpus luteumthecal cells, form the corpus luteum

The corpus luteum secretes progesterone and The corpus luteum secretes progesterone and estrogenestrogen

If pregnancy does not occur, the corpus luteum If pregnancy does not occur, the corpus luteum degenerates in 10 days, leaving a scar (corpus degenerates in 10 days, leaving a scar (corpus albicans)albicans)

If pregnancy does occur, the corpus luteum If pregnancy does occur, the corpus luteum produces hormones until the placenta takes over produces hormones until the placenta takes over that role (at about 3 months)that role (at about 3 months)

Establishing the Ovarian CycleEstablishing the Ovarian Cycle

During childhood, ovaries grow and During childhood, ovaries grow and secrete small amounts of estrogens that secrete small amounts of estrogens that inhibit the hypothalamic release of GnRHinhibit the hypothalamic release of GnRH

As puberty nears, GnRH is released; FSH As puberty nears, GnRH is released; FSH and LH are released by the pituitary, which and LH are released by the pituitary, which act on the ovariesact on the ovaries

These events continue until an adult cyclic These events continue until an adult cyclic pattern is achieved and menarche occurspattern is achieved and menarche occurs