Histology of the Ovary and Ovarian Follicles [Female Reproductive Histology Part 1 of 2]

Summary

This video from the Da Vinci Academy's histology course on YouTube explores the female reproductive system's anatomy and histology. It delves into the ovaries' structure, detailing the development stages of ovarian follicles, from primordial to mature, and the role of the corpus luteum in hormone secretion. The script also explains the process of atresia and the importance of the endocrine system in the reproductive cycle, offering a comprehensive guide for students and professionals in the field.

Takeaways

• 📚 The Da Vinci Academy's histology video course is available on YouTube, covering fundamental principles of histology and cell biology.
• 🔍 The course includes a lecture on the female reproductive system, detailing its anatomy and histological organization.
• 👩‍⚕️ The female reproductive system comprises the ovaries, uterus, fallopian tubes, cervix, and vagina, playing a role in endocrine regulation and reproduction.
• 🌱 The ovaries are covered by a fibrous capsule called the tunica albuginea, which is less defined than in testes.
• 🌼 The ovarian cortex contains follicles at various stages of growth, including primordial, primary, secondary, and mature follicles.
• 🌿 The primordial follicles are immature and formed during the embryonic period, while primary follicles begin to grow under the influence of FSH.
• 🌀 The multilaminar primary follicles feature multiple layers of granulosa cells and the development of the zona pellucida.
• 💧 Secondary or antral follicles are characterized by fluid-filled spaces within the granulosa cells.
• 🍊 The mature follicles, or Graafian follicles, have a large fluid-filled space called the antrum and are ready for ovulation.
• 🔄 Atresia refers to the degeneration of follicles at any stage, marked by apoptosis of oocytes and granulosa cells.
• 🟡 The corpus luteum is a temporary endocrine structure formed after ovulation, secreting progesterone and estrogen, and can transform into the corpus albicans if fertilization does not occur.

Q & A

Where can I find the complete histology video course mentioned in the script?

The complete histology video course is available on YouTube, and you can access it through the histology playlist link provided in the description below the video.

What are the main components of the female reproductive system discussed in the script?

The main components of the female reproductive system discussed are the ovaries, uterus, uterine tubes (fallopian tubes), the dome-shaped fundus, the main body of the uterus, the cervix, and the vagina.

What is the tunica albuginea, and how does it differ in the ovaries compared to the testes?

The tunica albuginea is a fibrous connective tissue capsule covering certain organs. In the ovaries, it is not as well-defined, thick, or dense as it is in the testes.

What is the germinal epithelium, and why is it a misnomer in the case of the ovaries?

The germinal epithelium is a single layer of simple cuboidal cells surrounding the ovarian surface. It is a misnomer because, when first discovered, it was thought to be the germ cells themselves that gave rise to the oocytes, but this is not the case.

What is the role of the primordial follicles in the ovaries?

Primordial follicles are immature follicles present in the ovarian cortex and are the majority type of follicles seen before puberty. They contain primary oocytes that are arrested at prophase one of meiotic cell division.

How does the ovary respond to the release of gonadotropin-releasing hormones during puberty?

During puberty, the release of gonadotropin-releasing hormones (GnRH) leads to the secretion of follicle-stimulating hormone (FSH) from the anterior pituitary, which stimulates the growth of several follicles in the ovary.

What are the different types of ovarian follicles mentioned in the script, and how do they differ?

The different types of ovarian follicles mentioned are the uni-laminar primary follicle, multi-laminar primary follicle, antral or secondary follicle, mature or graafian follicle, and atretic follicle. They differ in their stages of growth, the number of layers of granulosa cells, and the presence of fluid-filled spaces.

What is the significance of the zona pellucida in the development of follicles?

The zona pellucida is an acellular barrier that forms on the external surface of the oocyte. It plays an important role in blocking spermatocytes from directly entering the oocyte.

What happens to the mature follicle just before ovulation?

Just before ovulation, the primary oocyte in the mature follicle is triggered to finish meiosis I and enter meiosis II, becoming a secondary oocyte, which is arrested at metaphase.

What is atresia, and how does it relate to the follicles in the ovaries?

Atresia refers to the absence, incomplete formation, or degeneration of structures. In the ovaries, numerous follicles at any stage of growth can undergo atresia, which is characterized by signs of apoptosis in both the primary oocytes and granulosa cells.

What is the function of the corpus luteum, and what happens to it in the absence of fertilization?

The corpus luteum is formed from the remaining granulosa and theca cells after ovulation and secretes progesterone and estrogen, which are crucial for preparing the uterine endometrium for a potential fertilized egg. In the absence of fertilization, the corpus luteum degenerates after about 10 to 14 days, leading to menstruation.

Outlines

00:00

🌟 Introduction to Female Reproductive System Histology

This introductory paragraph sets the stage for the histology video course, highlighting its availability on YouTube and the comprehensive coverage of histology and cell biology principles. The focus is on the female reproductive system, starting with the general anatomy and moving into the histological organization of the ovaries and follicles. Key structures such as the ovaries, uterus, fallopian tubes, and vagina are introduced, along with their roles in the reproductive cycle and endocrine regulation. The paragraph also delves into the macroscopic view of the ovaries, discussing the tunica albuginea and the cortical layer containing various follicles and corpus luteum, emphasizing their importance in reproduction and hormonal functions.

05:02

📚 Detailed Examination of Ovarian Follicles and Their Development

This paragraph provides an in-depth look at the types of ovarian follicles, their development stages, and the hormonal processes involved. It begins with the primordial follicles and the onset of puberty, leading to the stimulation of follicle growth by gonadotropin-releasing hormones. The description progresses through the various stages of follicular development, including uni-laminar primary, multi-laminar primary, antral (secondary), mature (graafian), and atretic follicles. Each stage is characterized by specific morphological features and the role of the granulosa cells in supporting oocyte development. The paragraph also explains the process of follicle maturation, including the formation of the zona pellucida and the theca layers, which are crucial for hormone production and follicle function.

10:05

🔍 The Maturation and Ovulation of the Oocyte

This section delves into the final stages of follicle development, leading up to ovulation. It describes the mature follicle, characterized by the presence of a fluid-filled antrum, and the changes that occur just before ovulation, including the completion of meiosis I. The paragraph explains the arrest of the secondary oocyte at metaphase of meiosis II, which will only be completed upon fertilization. It also discusses the movement of the mature follicle towards the ovarian surface in preparation for ovulation and the protective role of the corona radiata and cumulus oophorus. The importance of these structures in the process of oocyte release and potential fertilization is emphasized.

15:06

💡 Atresia and the Role of the Corpus Luteum

This paragraph addresses the phenomenon of atresia, where follicles undergo degeneration at various stages of development. It highlights the constant presence of atresia from the fetal stage to menopause and describes the histological signs of apoptosis in degenerating follicles. The discussion then shifts to the corpus luteum, a temporary endocrine structure that forms from the remnants of the ovulated follicle. The role of the corpus luteum in producing progesterone and estrogen is detailed, along with its importance in preparing the uterus for potential fertilization. The paragraph also explains the life cycle of the corpus luteum, from its formation after ovulation to its degeneration in the absence of fertilization, leading to menstruation.

20:08

🌱 The Impact of Pregnancy on the Corpus Luteum and Ovarian Aging

The final paragraph discusses the impact of successful fertilization and pregnancy on the corpus luteum. It explains how the placenta's secretion of human chorionic gonadotropin (hCG) sustains and stimulates the growth of the corpus luteum, prolonging its production of progesterone and estrogen. The paragraph also describes the eventual regression of the corpus luteum after the first trimester of pregnancy as the placenta takes over hormone production. It concludes with an overview of the aging process in the ovaries, where the accumulation of corpora albicans, resulting from the degeneration of corpora lutea, contributes to the visible aging changes in the ovaries over time.

Keywords

💡Histology

Histology is the study of the microscopic anatomy of tissues and cells. In the context of this video, it is the core discipline that provides insights into the structure and function of the female reproductive system. The script discusses various histological features of the ovaries, such as the tunica albuginea and the follicles, which are crucial for understanding their role in reproduction.

💡Female Reproductive System

The female reproductive system is the biological system in females involved in human reproduction. The script provides an overview of its components, including the ovaries, uterus, fallopian tubes, and vagina, highlighting their roles in the reproductive cycle and endocrine regulation.

💡Ovaries

Ovaries are a pair of female reproductive organs that produce eggs and female sex hormones. The script delves into the macroscopic and histological organization of the ovaries, including the tunica albuginea and the various types of follicles, which are essential for oogenesis and hormone production.

💡Follicles

Follicles are structures in the ovaries that contain immature oocytes. The script describes different types of follicles, such as primordial, primary, secondary, and mature follicles, each with unique histological characteristics that are vital for the process of ovulation and the reproductive cycle.

💡Corpus Luteum

The corpus luteum is a temporary endocrine structure in the ovary that forms after ovulation. The script explains its formation from the remnants of the mature follicle and its role in producing progesterone and estrogen, which are critical for preparing the uterus for potential fertilization.

💡Atresia

Atresia refers to the degeneration of ovarian follicles at any stage of development. The script mentions atretic follicles, which are characterized by apoptosis of the oocyte and granulosa cells, illustrating the natural process of follicular attrition in the ovaries.

💡Zona Pellucida

The zona pellucida is a glycoprotein layer surrounding the oocyte that plays a role in fertilization by preventing sperm from entering directly. The script describes its presence in various types of follicles and its importance in the process of oocyte maturation and fertilization.

💡Granulosa Cells

Granulosa cells are a type of cell found in the ovaries that support the growth and development of follicles. The script details their transformation from follicular cells to granulosa cells and their role in hormone production within different types of follicles.

💡Theca Cells

Theca cells are stromal cells surrounding the granulosa cells in ovarian follicles. The script explains their differentiation into theca interna and theca externa, which play different roles in hormone production, such as the conversion of androgens to estrogens.

💡Germinal Epithelium

The germinal epithelium, also known as the sorosal layer, is a single layer of simple cuboidal cells on the ovarian surface. The script clarifies that it was historically thought to be involved in oocyte production, but this is now known to be a misnomer, although the term remains in use.

💡Primordial Follicles

Primordial follicles are immature follicles present in the ovaries from the embryonic period. The script describes their histological appearance and their significance as the starting point for follicular development during puberty and the reproductive years.

Highlights

The entire histology video course is available on YouTube, covering fundamental principles of histology and relevant cell biology.

Access to the histology playlist and practice questions is provided through links in the video description.

The female reproductive system lecture discusses the general anatomy and histological organization of the ovaries and various follicles.

The ovaries are suspended within the pelvic cavity by the suspensory and ovarian ligaments.

The uterus is a large pear-shaped structure with two fallopian tubes, a fundus, body, cervix, and vagina.

The ovaries are covered by a fibrous connective tissue capsule called the tunica albuginea.

The ovarian parenchyma is divided into the outer cortical layer containing follicles and the inner medulla.

The cortex contains follicles in various stages of growth, including diverse histology of follicles and corpus luteum.

The germinal epithelium, a misnomer, is a single layer of simple cuboidal cells surrounding the ovarian surface.

The tunica albuginea is an ill-defined layer of dense irregular connective tissue.

Primordial follicles are immature follicles present before puberty, contained within the ovarian cortex.

Follicle stimulating hormone (FSH) stimulates the growth of several follicles each month during the reproductive years.

Different types of ovarian follicles are identifiable based on characteristic morphologies, such as primary, secondary, and mature follicles.

The mature follicle, or Graafian follicle, is characterized by a single enlarged fluid-filled space called the antrum.

Atresia refers to the degeneration of follicles at any stage of growth, observable through signs of apoptosis.

The corpus luteum is a yellow body formed from the remnants of the mature follicle post-ovulation, secreting progesterone and estrogen.

The lifespan of the corpus luteum is approximately 10 to 14 days, degrading in the absence of fertilization and placenta formation.

In the case of successful fertilization, the corpus luteum persists and proliferates due to human chorionic gonadotropin (hCG).

After about five months of pregnancy, the placenta takes over progesterone and estrogen production, allowing the corpus luteum to regress.

Corpus albicans is the dense irregular connective tissue scar that remains after the corpus luteum degenerates.

Transcripts

welcome to the da vinci academy

histology video course

the entire video course is available on

youtube and covers all of the

fundamental principles of histology and

relevant cell biology you can find all

the videos from the course by clicking

the histology playlist link in the

description below

and then you can access the

corresponding practice questions and

histology lab videos by going to our

website which is also linked in the

description below this first female

reproductive system lecture will discuss

the general anatomy of the female

reproductive system and dive into the

histological organization of the ovaries

and variety of follicles

female reproductive system consists of

the two ovaries which are suspended

within the pelvic cavity by the

suspensory ligament which goes up

laterally and superiorly in this fashion

and the ovarian ligament which attaches

the medial aspect of the ovaries to the

lateral aspect of the uterine body

another component of the female

reproductive system would be the uterus

which is this large pear-shaped

structure which has these two uterine

tubes also known as the fallopian tubes

the dome-shaped fundus the main body and

the narrowed inferior portion called the

cervix and it also includes the vagina

which is this fibromuscular tube leading

out into the external opening and while

these organs lay quote-unquote dormant

during childhood from monarchy to

menopause these structures play a

critical role in endocrine regulation of

reproductive cycle as well as the

reproduction itself looking at the

ovaries at macroscopic scale each ovary

is covered on the outside by a fibrous

connective tissue capsule called the

tunica elbogenia it's not quite as well

defined or clear in the ovaries because

it is not as thick or dense as it is in

the testes so dr cooper will discuss

tunica albuginea covering the testes

this structure is comprised of the dense

irregular connective tissue and it forms

a bit of a capsule-like structure for

the ovaries as well as in the testes

the parenchyma of the ovaries are

subdivided into the outer cortical layer

and the inner medulla the cortical layer

contains numerous follicles which are

the oocytes that are surrounded by the

protective ovarian stromal cells and

during the reproductively active age

this cortex will contain the follicles

that are in various stages of growth as

you can see here there's diverse

histology of these follicles of various

sizes in addition to various sizes and

shapes of follicles we may also see some

corpus luteum which is the leftover

follicular cells after the follicle has

ovulated that release progesterone and

estrogen looking at these structures

histologically at a higher magnification

the outermost layer of the ovaries so

we're talking about even external to the

tunica alpha genia we see that there's

actually a single layer of simple

cuboidal cells that surround the ovarian

surface this structure is called the

germinal epithelium this is actually a

sorosal layer that drapes over the

ovaries and here the sorceal cells are

not squamous but instead are cuboidal to

columnar in shape so here's higher

magnification of the external surface of

the ovary we can see that here is that

loosely defined tunica albugenia and

outside of that we're seeing this simple

cuboidal epithelial tissue this is the

germinal epithelium aka the sorosaur

layer when this layer was first

discovered they were actually thought to

be the germ cells themselves that gave

rise to the oocytes hence the term

germinal epithelium which we now know is

actually not the case but unfortunately

this name kind of stuck around so it's

important to know that this germinal

epithelium is actually a misnomer in the

testes however there are also

histological structures called the

germinal epithelium but in the case of

testes the germinal epithelium is

actually an appropriate name since it is

actually referring to the structures

that produce the spermatocytes and that

will be highlighted in the male

reproductive system lecture the tunica

albuginea as mentioned before is an

ill-defined layer of dense irregular

connective tissue surrounding the outer

layer of the ovaries but now deep to the

germinal epithelium now during fetal and

childhood periods the ovarian cortex

about this region contains hundreds of

thousands of immature follicles called

the primordial follicles in the

background of ovarian stroma so the

primordial follicles would be the

majority type of follicles we would see

before puberty however starting at

puberty when the hypothalamus starts to

release the gonadotropin releasing

hormones or the gnrh the basophils in

the anterior pituitary will start to

secrete the follicle stimulating hormone

or the fsh which then starts to simulate

several follicles every month to start

to grow so as a result during the

reproductively active years a variety of

follicles in different stages of growth

are observed in the ovarian cortex and

based on some characteristic

morphologies and based on some

characteristic morphologies there are

different types of identifiable ovarian

follicles that are called different

names such as the uni laminar primary

follicle multilaminar primary the antral

or the secondary follicles and the

mature or graphene follicles and the

atretic follicles so let's look at each

one's histology a little closer the

primordial follicle is something like

this

these and as the name suggests these are

the most immature forms of follicles

that actually formed during the

embryonic period and stuck around the

primordial follicle is comprised of the

primary oocyte which is the spherical

cell with large cell cytoplasm and

nucleus and the primary oocyte is

actually arrested at prophase one of

meiotic cell division so it may still

contain the nucleus with intact nuclear

envelope but we may see some thready

chromosomes that have condensed and are

waiting to separate such primary oocyte

in the primordial follicle is surrounded

by a single layer of flattened ovarian

stromal cells called the follicular

cells which provides supportive roles

for the primary oocytes the uni laminar

primary follicles are essentially the

primordial follicles that have started

to grow under the influence of follicle

stimulating hormone so the uni laminar

primary follicles are characterized by

the larger size of the primary oocytes

so here is the oocyte that has grown a

bit in size here's the primordial

follicle with the primary oocyte for

comparison and at this stage in

follicular growth the flattened

follicular cells have actually

transformed into a cuboidal histology so

the primary oocytes in the unilaminar

primary follicles are surrounded by a

single layer of larger follicular cells

at which point the follicular cells are

now called the granulosa cells and here

is another uni-laminar primary follicle

that is surrounded by a single layer of

cuboidally shaped granulosa cells note

also the ovarian stroma the connective

tissue component of the ovary is

actually quite cellular and as the

follicles start to grow the stromal

cells themselves especially the ones

that are immediately surrounding the

follicles will kind of arrange

themselves into

spherical conformation and later on

these stromal cells too will start to

provide some supportive roles as well

now the continued growth of the

follicles under the fsh influence will

result in a more mature form of

follicles called a multi-laminar primary

follicle here the primary oocyte is

getting larger still and we didn't quite

catch the nucleus here and this probably

has more to do with the plane of suction

than the fact that this cell is lacking

the nucleus since the oocytes are quite

large cells at any rate the oocytes

themselves start to accumulate this

acellular barrier on its external

surface called the zona pellucida which

directly translates to the pale zone

this structure plays an important role

in blocking out the spermatocytes from

directly entering the oocyte now outside

the zona pellucida the granulosa cells

themselves have undergone quite a bit of

proliferation so as opposed to having a

single layer of cuboidal granulosa cells

we now have multiple layers hence the

name the multilaminar primary follicle

another thing that is noticeable here is

the clear boundary between the outermost

layer of the granulosa cells and the

surrounding stromal cells and the

stromal cells that are immediately

outside this boundary start to actually

enlarge and form a layer of capsule-like

structure called the thicker layer so

this would be the thicker layer that is

comprised of the stromal cells and

around at this point the stromal cells

that are immediately outside this

basement membrane start to secrete the

precursors of estrogen called the

angiosynodone for the granulosa cells to

convert to the proper estradiol which

would then be released into the

bloodstream to stimulate the uterine

endometrial growth so as the follicle

itself is growing it is starting to

release these hormonal products that the

uterine glands can respond to the

continued growth of multi-laminar

primary follicles leads to this

structure called the anterol or the

secondary follicle which is

characterized by these fluid-filled

spaces that start to accumulate within

the granulosa cells so again

enterofollicles have the primary oocytes

that are arrested at the prophase one of

meiosis they have still the zona

pellucida that is surrounding the

outside of the oocyte and then we have

the multiple layers of granulosa cells

but this time we have these fluid-filled

spaces that'll start to eventually kind

of coalesce into bigger and bigger

fluid-filled spaces as the follicle

itself grows what's interesting also is

that as the follicles are growing they

start to move towards the medulla of the

ovary where the source of vasculature

and fluids are located in the form of

helicine arteries and veins another

unique feature about the enteral

follicles is that the this thicker layer

the stromal cells outside the granulosa

layer will start to differentiate into

the inner and the outer deca layer with

the dica internal layer being comprised

of a bit larger stromal cells and the

external layer deca externa being

comprised of more of a flattened stromal

cells that form an indistinct

capsule-like structure and these two

thicker layers will become more and more

distinct as the follicle itself grows

larger and larger nigentica interna has

the endocrine function of producing the

androcynodione which then the granulosa

cells can convert to the estradiol the

estrogen product that is released into

the bloodstream and now we have the

mature follicles this is the most well

developed and the largest of the

follicles that are characterized by a

single enlarged fluid filled space

called the antrum the oocyte is still a

primary oocyte that's arrested at

prophase one of meiosis

and at this point outside the granulosa

cell layer of this mature follicle we

can really see the distinctive deca

interna cells comprised of larger

spindle-shaped cells versus the tica

extrana which is comprised of the

flattened stromal cells that are

essentially forming an indistinct

capsule-like structure and the internal

aspect of the mature follicle we can see

that the outside of the zona pellucida

we have this layer of granulosa cells

that are forming kind of a protective

outer covering of the primary oocyte

this outer layer of granulosa cells are

collectively called the corona radiata

for resembling a radiating crown if you

will and then we can also see another

collection of granulosa cells that are

attaching this oocyte complex to the

rest of the granulosa cell layer on the

outer aspect of the follicle and this

region or structure is collectively

called the cumulus ovaries and as this

mature follicle also known as the

graafian follicle starts to enlarge this

growing follicles will actually start to

come back up towards the tunica virginia

towards the surface of the ovary in

preparation for the ovulation of this

oocyte complex and up until this point

the primary oocyte is still arrested in

prophase one but just before the

ovulation the oocyte is triggered to

finish meiosis 1 and enter meiosis ii

thus becoming a secondary oocyte but

even the secondary oocyte as the

ovulation occurs is arrested again at

meiosis ii at metaphase so once the

oocyte is ovulated this oocyte can now

be called the secondary oocyte it is

surrounded on the outside by the zona

pellucida as well as several layers of

granulosa cells aka the corona radiata

the secondary oocytes are arrested at

meiosis ii at metaphase and this meiotic

division will not finish until

fertilization is successfully achieved

now lastly the atritic follicles atresia

itself refers to the absence or

incomplete formation or even

degeneration so in the ovaries numerous

follicles at any stage of growth can

undergo atresia and this is actually

happening at all times from fetal stage

up until menopause so it is not uncommon

to observe atritic follicles or the ones

that are degenerating in the ovaries

especially the larger follicles that are

undergoing atresia are histologically

quite noticeable by the abundant signs

of apoptosis not only of the primary

oocytes but also of the numerous

granulosa cells so again the atritic

follicles are referring to the

degenerating follicles at various stages

of growth and they're recognized by the

science of apoptosis where the cell

membranes of the apoptotic cells are not

distinctive at all including even that

of the oocyte and some other signs of

apoptosis would be a lot of these

hypnotic or really condensed nuclei and

cellular debris and furthermore the

general tissue integrities of the

follicles are lost as the apoptotic

cells are essentially sloughing off and

floating into the antrum if you will so

again such atritic follicles are not at

all uncommon to see and observe in the

ovarian histology

now during reproductive years in

addition to a variety of follicles the

corpus luteum may be observed as well in

the ovarian cortex the corpus refers to

the body ludium or ludia refers to the

color yellow so corpus luteum literally

translates to the yellow body so this is

a yellow body of about one to two

centimeter diameter structure that can

actually be observed with naked eyes on

the ovarian cortex without the aid of

microscopes the corpus luteum is

actually formed by what's remaining of

the mature follicle after it has

ovulated or released the oocyte complex

into the peritoneum so this ill-defined

cellular structure in the corpus luteum

is comprised of the remaining granulosa

cells and the deca cells that have kind

of collapsed onto themselves at this

point the granulosa cells are called the

granulosa ludian cells and the tica

internal cells become the thicker ludian

cells the reason why the corpus luteum

appears as this yellow body under naked

eye observation is due to the rich

steroid hormones especially the

progesterone in addition to the estrogen

that are being secreted by the granulosa

lutein and dicaludian cells

the progesterone in particular that's

released by the corpus luteum plays such

an important role in signaling the

endometrial glands to not only stick

around but start to secrete glandular

fluids in anticipation of the fertilized

product to arrive into the uterus an

interesting fact about the corpus luteum

is that they naturally have about the

lifespan of 10 to 14 days to release the

progesterone and estrogen but in the

absence of fertilization and

particularly the placenta formation in

the uterus the corpus luteum will start

to degenerate after about 14 days and

with their involution or degeneration

the uterine endometrial glands will

start to shed resulting in menstruation

and as the corpus luteum itself

degenerates numerous macrophages and

fibroblasts will come in and replace

this structure with dense irregular

connective tissue scar thereby becoming

the corpus albicans or the white bodies

in case of successful fertilization and

the implantation of the conceptus in the

uterus however there's this developing

placenta that'll start to secrete the

human chorionic gonadotropin or the hcg

and hcg will actually signal the corpus

luteum to persist in fact not only

persists but also to proliferate and

really crank up the production of

progesterone in addition to the estrogen

in order to sustain the uterine

endometrial glands so the corpus luteum

ends up sticking around and growing for

up to about five months into pregnancy

in fact the corpus luteum during

pregnancy can get quite large it can

hypertrophy

quite significantly to about half the

size of the ovary itself it's quite

remarkable but after about five months

the placenta itself can start to produce

its own progesterone and estrogen level

and at that point the corpus luteum can

start to ingress and eventually

degenerate so the corpus albicans or

corpora albicansia in plural are what

remains after corpus luteum degenerates

and becomes replaced with the scar

tissue so histologically the corpus

albicans looks like dense irregular

connective tissue with lots and lots of

collagen type 1 fibers and flattened

fibrocytes that are wedged in between

and albicans once again refers to the

color white which is attributable to the

grayish whitish collagen fibers that can

be observed with naked eyes so with

increasing age we can imagine how more

and more corpora ludia are forming than

degenerating therefore the number of

corpora albicans will start to

accumulate an increase in number with

age thank you for watching this video

from the da vinci academy histology

video course which is completely

available on youtube to access the

corresponding practice questions and

histology lab videos go to our website

using the link in the description below

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so

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you