Normal Reproductive physiology and anatomy
Anatomy and microanatomy of the female reproductive system:
Ovaries- most important component of this system and are the site of oogenesis (maturation and
development of follicle before release of oocyte occurs here). The oocytes are present form birth in a fixed
number (arrested in meiotic prophase I) and decrease during life.
Prepubertal surface of the ovary is smooth = becomes scarred following puberty caused by the eruption of
oocytes
The ovaries have two main functions: to produce the mature ova and to act as an endocrine organ
synthesising and secreting the steroid hormones, oestrogen and progesterone, necessary for conception & the
maintenance of pregnancy. These are released in response to FSH and LH (secreted via anterior
pituitary).
Cross section of ovary:
You can see the follicles in different stages of development, from early to late stages.
There are 3 regions of the ovary:
Hilum: stuff goes in and out (entrance way of blood vessels, nerves
and lymphatics into the ovary).
Medulla: located in the middle of the ovary, it mostly vascularised
loose connective tissue.
Cortex: around the outside of ovary. This is where the ovarian follicles are
located. So, the developing oocytes are found here and are surrounded by
dense irregular connective tissue- stroma.
Looking deeply at the cortex, we can see the developing oocytes and the
dark pink bits around it is the stroma, which supports the oocyte. On the
very outer surface of the ovary there is the germinal epithelium layer (it
doesn’t relate to germ cells). This can be considered as modified
peritoneum (equivalent to the visceral peritoneum). Underneath this
epithelial layer, there is the tunica albuginea (CT)- white fibrous coating on
the outside of the ovary. It is through these structures – tunica albuginea
and germinal epithelium that the oocyte ruptures to be release into the
peritoneal cavity – to be collected by the fimbriae. This stuff is important
due to ovarian cancer- as origin of 85-90% of ovarian cancers is due to the
germinal epithelium.
Uterine Tube:
This is a smooth muscular tube which allows the movement of our oocyte or our zygote through it down
towards the uterus via peristalsis. It is also the site of fertilisation. The tube is about 10cm long and lies
between the folds of broad ligaments of the uterus. Like the uterus and vagina, the fallopian tube is an
epithelial mucosa, a muscle layer and a supporting connective tissue.
Uterine tube has 4 different parts to it:
1. Infundibulum: on the outside of this there is the fimbriae which capture oocyte once it is released.
2. Ampulla: widest part of the uterine tube, convoluted thin wall. This is where fertilisation is most likely
to occur.
, 3. Isthmus: “bridge” between the ampulla and the uterus. It has a very thick wall and is narrow and
straight – important for peristalsis.
4. Intramural: “within wall” of the uterine cavity.
Epithelium of the uterine tubes:
The isthmus has a much thicker wall compared to the ampulla. Within the ampulla there are highly convoluted
mucosal folds which helps to increase the surface area which allows oocyte to pass down and stay in contact
with the wall as well as controlling the movement of the zygote/oocyte towards the uterus.
There are 2 types of epithelium which line these mucosal folds: both simple columnar epithelium but 2
different types of cells:
Secretory/Peg cells: these produce watery secretions which helps to nourish oocyte/zygote in its path
so before and after fertilisation.
Ciliated cells: epithelia have cilia on top of it and the length of the cilia changes in response to
hormones- more oestrogen causes them to get longer which also increases the beat rate,
progesterone causes them to shrink – waft oocyte down the tube, though the peristaltic movement of
the muscle layers may be more effective at moving the ova and sperm than the cilia.
These are the cells which are most affected by micro-organisms e.g. chlamydia (affect cilia) and cysts
forming within epithelia. This makes it harder for movement towards the uterine tube. This explains
STI’s can increase risk of ectopic pregnancy as it can’t get its way along tube to implanted elsewhere
or can lead to sterility.
Anatomy and microanatomy of the female reproductive system:
Ovaries- most important component of this system and are the site of oogenesis (maturation and
development of follicle before release of oocyte occurs here). The oocytes are present form birth in a fixed
number (arrested in meiotic prophase I) and decrease during life.
Prepubertal surface of the ovary is smooth = becomes scarred following puberty caused by the eruption of
oocytes
The ovaries have two main functions: to produce the mature ova and to act as an endocrine organ
synthesising and secreting the steroid hormones, oestrogen and progesterone, necessary for conception & the
maintenance of pregnancy. These are released in response to FSH and LH (secreted via anterior
pituitary).
Cross section of ovary:
You can see the follicles in different stages of development, from early to late stages.
There are 3 regions of the ovary:
Hilum: stuff goes in and out (entrance way of blood vessels, nerves
and lymphatics into the ovary).
Medulla: located in the middle of the ovary, it mostly vascularised
loose connective tissue.
Cortex: around the outside of ovary. This is where the ovarian follicles are
located. So, the developing oocytes are found here and are surrounded by
dense irregular connective tissue- stroma.
Looking deeply at the cortex, we can see the developing oocytes and the
dark pink bits around it is the stroma, which supports the oocyte. On the
very outer surface of the ovary there is the germinal epithelium layer (it
doesn’t relate to germ cells). This can be considered as modified
peritoneum (equivalent to the visceral peritoneum). Underneath this
epithelial layer, there is the tunica albuginea (CT)- white fibrous coating on
the outside of the ovary. It is through these structures – tunica albuginea
and germinal epithelium that the oocyte ruptures to be release into the
peritoneal cavity – to be collected by the fimbriae. This stuff is important
due to ovarian cancer- as origin of 85-90% of ovarian cancers is due to the
germinal epithelium.
Uterine Tube:
This is a smooth muscular tube which allows the movement of our oocyte or our zygote through it down
towards the uterus via peristalsis. It is also the site of fertilisation. The tube is about 10cm long and lies
between the folds of broad ligaments of the uterus. Like the uterus and vagina, the fallopian tube is an
epithelial mucosa, a muscle layer and a supporting connective tissue.
Uterine tube has 4 different parts to it:
1. Infundibulum: on the outside of this there is the fimbriae which capture oocyte once it is released.
2. Ampulla: widest part of the uterine tube, convoluted thin wall. This is where fertilisation is most likely
to occur.
, 3. Isthmus: “bridge” between the ampulla and the uterus. It has a very thick wall and is narrow and
straight – important for peristalsis.
4. Intramural: “within wall” of the uterine cavity.
Epithelium of the uterine tubes:
The isthmus has a much thicker wall compared to the ampulla. Within the ampulla there are highly convoluted
mucosal folds which helps to increase the surface area which allows oocyte to pass down and stay in contact
with the wall as well as controlling the movement of the zygote/oocyte towards the uterus.
There are 2 types of epithelium which line these mucosal folds: both simple columnar epithelium but 2
different types of cells:
Secretory/Peg cells: these produce watery secretions which helps to nourish oocyte/zygote in its path
so before and after fertilisation.
Ciliated cells: epithelia have cilia on top of it and the length of the cilia changes in response to
hormones- more oestrogen causes them to get longer which also increases the beat rate,
progesterone causes them to shrink – waft oocyte down the tube, though the peristaltic movement of
the muscle layers may be more effective at moving the ova and sperm than the cilia.
These are the cells which are most affected by micro-organisms e.g. chlamydia (affect cilia) and cysts
forming within epithelia. This makes it harder for movement towards the uterine tube. This explains
STI’s can increase risk of ectopic pregnancy as it can’t get its way along tube to implanted elsewhere
or can lead to sterility.
