# Human Physiology/The female reproductive system

## Introduction

All living things reproduce. This is something that sets the living
apart from non-living. Even though the reproductive system is essential
to keeping a species alive, it is not essential to keeping an individual
alive. This chapter describes the different parts of the female
reproductive system: the organs involved in the process of reproduction,
hormones that regulate a woman\'s body, the menstrual cycle, ovulation
and pregnancy, the female\'s role in genetic division, birth control,
sexually transmitted diseases and other diseases and disorders.

### Reproduction

Reproduction can be defined as the process by which an organism
continues its species. In the human reproductive process, two kinds of
sex cells ( gametes), are involved: the male gamete (sperm), and the
female gamete (egg or ovum). These two gametes meet within the female\'s
uterine tubes located one on each side of the upper pelvic cavity, and
begin to create a new individual. The female needs a male to fertilize
her egg; she then carries offspring through pregnancy and childbirth.

#### Similarities between male and female reproductive systems

The reproductive systems of the male and female have some basic
similarities and some specialized differences. They are the same in that
most of the reproductive organs of both sexes develop from similar
embryonic tissue, meaning they are homologous. Both systems have gonads
that produce (sperm and egg or ovum) and sex organs. And both systems
experience maturation of their reproductive organs, which become
functional during puberty as a result of the gonads secreting sex
hormones. !The human male reproductive
system{width="440"}

!Cross-sectional diagram of the female reproductive
organs.{width="440"}
In short, this is a known list of sex organs that evolve from the same
tissues in a human life.

  Undifferentiated      Male                                Female
  --------------------- ----------------------------------- --------------------------
  Gonad                 Testis                              Ovary
  Müllerian duct        Appendix testis                     Fallopian tubes
  Müllerian duct        Prostatic utricle                   Uterus, proximal
  Wolffian duct         Rete testis                         Rete ovarii
  Mesonephric tubules   Efferent ducts                      Epoophoron
  Wolffian duct         Epididymis                          Gartner\'s duct
  Wolffian duct         Vas deferens
  Wolffian duct         Seminal vesicle
  Wolffian duct         Prostate                            Skene\'s glands
  Urogenital sinus      Urinary bladder\|Bladder, urethra   Bladder, urethra, distal
  Urogenital sinus      Bulbourethral gland                 Bartholin\'s gland
  Genital swelling      Scrotum                             Labia majora
  Urogenital folds      Distal urethra                      Labia minora
  Genital tubercle      Penis                               Clitoris
  Prepuce                                                   Clitoral hood
                        Bulb of penis                       Vestibular bulbs
                        Glans penis                         Clitoral glans
                        Crus of penis                       Clitoral crura

#### Differences between male and female reproductive systems

The differences between the female and male reproductive systems are
based on the functions of each individual\'s role in the reproduction
cycle. A male who is healthy, and sexually mature, continuously produces
sperm. The development of women\'s \"eggs\" are arrested during fetal
development. This means she is born with a predetermined number of
oocytes and cannot produce new ones.

At about 5 months gestation, the ovaries contain approximately six to
seven million oogonia, which initiate meiosis. The oogonia produce
primary oocytes that are arrested in prophase I of meiosis from the time
of birth until puberty. After puberty, during each menstrual cycle, one
or several oocytes resume meiosis and undergo their first meiotic
division during ovulation. This results in the production of a secondary
oocyte and one polar body. The meiotic division is arrested in metaphase
II. Fertilization triggers completion of the second meiotic division and
the result is one ovum and an additional polar body.

The ovaries of a newborn baby girl contain about one million oocytes.
This number declines to 400,000 to 500,000 by the time puberty is
reached. On average, 500-1000 oocytes are ovulated during a woman\'s
reproductive lifetime.

When a young woman reaches puberty around age 10 to 13, a promary oocyte
is discharged from one of the ovaries every 28 days. This continues
until the woman reaches menopause, usually around the age of 50 years.
Occytes are present at birth, and age as a woman ages.

Female Reproductive System:

-   Produces eggs (ova)
-   Secretes sex hormones
-   Receives the male spermatazoa during
-   Protects and nourishes the fertilized egg until it is fully
    developed
-   Delivers fetus through birth canal
-   Provides nourishment to the baby through milk secreted by mammary
    glands in the breast

## External Genitals

![](Gray1229.png "Gray1229.png"){width="250"} **Vulva**

The external female genitalia is referred to as vulva. It consists of
the labia majora and labia minora (while these names translate as
\"large\" and \"small\" lips, often the \"minora\" can protrude outside
the \"majora\"), mons pubis, clitoris, opening of the urethra (meatus),
vaginal vestibule, vestibular bulbs, vestibular glands.

The term \"vagina\" is often improperly used as a generic term to refer
to the vulva or female genitals, even though - strictly speaking - the
vagina is a specific internal structure and the vulva is the exterior
genitalia only. Calling the vulva the vagina is akin to calling the
mouth the throat.

**Mons Veneris**

The **mons veneris**, Latin for \"mound of Venus\" (Roman Goddess of
love) is the soft mound at the front of the vulva (fatty tissue covering
the pubic bone). It is also referred to as the mons pubis. The mons
veneris protects the pubic bone and vulva from the impact of sexual
intercourse. After puberty, it is covered with pubic hair, usually in a
triangular shape. Heredity can play a role in the amount of pubic hair
an individual grows.

**Labia Majora**

The **labia majora** are the outer \"lips\" of the vulva. They are pads
of loose connective and adipose tissue, as well as some smooth muscle.
The labia majora wrap around the vulva from the mons pubis to the
perineum. The labia majora generally hides, partially or entirely, the
other parts of the vulva. There is also a longitudinal separation called
the pudendal cleft. These labia are usually covered with pubic hair. The
color of the outside skin of the labia majora is usually close to the
overall color of the individual, although there may be some variation.
The inside skin is usually pink to light brown. They contain numerous
sweat and oil glands. It has been suggested that the scent from these
oils are sexually arousing.

**Labia Minora**

Medial to the labia majora are the labia minora. The **labia minora**
are the inner lips of the vulva. They are thin stretches of tissue
within the labia majora that fold and protect the vagina, urethra, and
clitoris. The appearance of labia minora can vary widely, from tiny lips
that hide between the labia majora to large lips that protrude. There is
no pubic hair on the labia minora, but there are sebaceous glands. The
two smaller lips of the labia minora come together longitudinally to
form the prepuce, a fold that covers part of the clitoris. The labia
minora protect the vaginal and urethral openings. Both the inner and
outer labia are quite sensitive to touch and pressure.

**Clitoris**
!lang=en\|right\|thumb\|133px

The **clitoris**, visible as the small white oval between the top of the
labia minora and the clitoral hood, is a small body of spongy tissue
that functions solely for sexual pleasure. Only the tip or glans of the
clitoris shows externally, but the organ itself is elongated and
branched into two forks, the crura, which extend downward along the rim
of the vaginal opening toward the perineum. Thus the clitoris is much
larger than most people think it is, about 4\" long on average.

The clitoral glans or external tip of the clitoris is protected by the
prepuce, or clitoral hood, a covering of tissue similar to the foreskin
of the male penis. However, unlike the penis, the clitoris does not
contain any part of the urethra.

During sexual excitement, the clitoris erects and extends, the hood
retracts, making the clitoral glans more accessible. The size of the
clitoris is variable between women. On some, the clitoral glans is very
small; on others, it is large and the hood does not completely cover it.

**Urethra**

The opening to the urethra is just below the clitoris. Although it is
not related to sex or reproduction, it is included in the vulva. The
**urethra** is actually used for the passage of urine. The urethra is
connected to the bladder. In females the urethra is 1.5 inches long,
compared to males whose urethra is 8 inches long. Because the urethra is
so close to the anus, women should always wipe themselves from front to
back to avoid infecting the vagina and urethra with bacteria. This
location issue is the reason for bladder infections being more common
among females.

**Hymen**

The hymen is a thin fold of mucous membrane that separates the lumen of
the vagina from the urethral sinus. Sometimes it may partially cover the
vaginal orifice. The hymen is usually perforated during later fetal
development.

Because of the belief that first vaginal penetration would usually tear
this membrane and cause bleeding, its \"intactness\" has been considered
a guarantor of virginity. However, the hymen is a poor indicator of
whether a woman has actually engaged in sexual intercourse because a
normal hymen does not completely block the vaginal opening. The normal
hymen is never actually \"intact\" since there is always an opening in
it. Furthermore, there is not always bleeding at first vaginal
penetration. The blood that is sometimes, but not always, observed after
first penetration can be due to tearing of the hymen, but it can also be
from injury to nearby tissues.

A tear to the hymen, medically referred to as a \"transection,\" can be
seen in a small percentage of women or girls after first penetration. A
transection is caused by penetrating trauma. Masturbation and tampon
insertion can, but generally are not forceful enough to cause
penetrating trauma to the hymen. Therefore, the appearance of the hymen
is not a reliable indicator of virginity or chastity.

**Perineum**

The perineum is the short stretch of skin starting at the bottom of the
vulva and extending to the anus. It is a diamond shaped area between the
symphysis pubis and the coccyx. This area forms the floor of the pelvis
and contains the external sex organs and the anal opening. It can be
further divided into the urogenital triangle in front and the anal
triangle in back.

The perineum in some women may tear during the birth of an infant and
this is apparently natural. Some physicians however, may cut the
perineum preemptively on the grounds that the \"tearing\" may be more
harmful than a precise cut by a scalpel. If a physician decides the cut
is necessary, they will perform it. The cut is called an episiotomy.

## Internal Genitals

### Vagina

The **vagina** is a muscular, hollow tube that extends from the vaginal
opening to the cervix of the uterus. It is situated between the urinary
bladder and the rectum. It is about three to five inches long in a grown
woman. The muscular wall allows the vagina to expand and contract. The
muscular walls are lined with mucous membranes, which keep it protected
and moist. A thin sheet of tissue with one or more holes in it, called
the hymen, partially covers the opening of the vagina. The vagina
receives sperm during sexual intercourse from the penis. The sperm that
survive the acidic condition of the vagina continue on through to the
fallopian tubes where fertilization may occur.

The vagina is made up of three layers, an inner mucosal layer, a middle
muscularis layer, and an outer fibrous layer. The inner layer is made of
vaginal rugae that stretch and allow penetration to occur. These also
help with stimulation of the penis. microscopically the vaginal rugae
has glands that secrete an acidic mucus (pH of around 4.0.) that keeps
bacterial growth down. The outer muscular layer is especially important
with delivery of a fetus and placenta.

Purposes of the Vagina:

-   Receives a male\'s erect penis and semen during sexual intercourse.
-   Pathway through a woman\'s body for the baby to take during
    childbirth.
-   Provides the route for the menstrual blood (menses) from the uterus,
    to leave the body.
-   May hold forms of birth control, such as a diaphragm, FemCap, Nuva
    Ring, or female condom.

### Cervix

The **cervix** (from Latin \"neck\") is the lower, narrow portion of the
uterus where it joins with the top end of the vagina. Where they join
together forms an almost 90 degree curve. It is cylindrical or conical
in shape and protrudes through the upper anterior vaginal wall.
Approximately half its length is visible with appropriate medical
equipment; the remainder lies above the vagina beyond view. It is
occasionally called \"cervix uteri\", or \"neck of the uterus\".

During menstruation, the cervix stretches open slightly to allow the
endometrium to be shed. This stretching is believed to be part of the
cramping pain that many women experience. Evidence for this is given by
the fact that some women\'s cramps subside or disappear after their
first vaginal birth because the cervical opening has widened.

The portion projecting into the vagina is referred to as the portio
vaginalis or **ectocervix**. On average, the ectocervix is three cm long
and two and a half cm wide. It has a convex, elliptical surface and is
divided into anterior and posterior lips. The ectocervix\'s opening is
called the external os. The size and shape of the external os and the
ectocervix varies widely with age, hormonal state, and whether the woman
has had a vaginal birth. In women who have not had a vaginal birth the
external os appears as a small, circular opening. In women who have had
a vaginal birth, the ectocervix appears bulkier and the external os
appears wider, more slit-like and gaping.

The passageway between the external os and the uterine cavity is
referred to as the **endocervical canal**. It varies widely in length
and width, along with the cervix overall. Flattened anterior to
posterior, the endocervical canal measures seven to eight mm at its
widest in reproductive-aged women. The endocervical canal terminates at
the internal os which is the opening of the cervix inside the uterine
cavity.

During childbirth, contractions of the uterus will dilate the cervix up
to 10 cm in diameter to allow the child to pass through. During orgasm,
the cervix convulses and the external os dilates.

### Uterus

The **uterus** is shaped like an upside-down pear, with a thick lining
and muscular walls. Located near the floor of the pelvic cavity, it is
hollow to allow a blastocyte, or fertilized egg, to implant and grow. It
also allows for the inner lining of the uterus to build up until a
fertilized egg is implanted, or it is sloughed off during menses.

The uterus contains some of the strongest muscles in the female body.
These muscles are able to expand and contract to accommodate a growing
fetus and then help push the baby out during labor. These muscles also
contract rhythmically during an orgasm in a wave like action. It is
thought that this is to help push or guide the sperm up the uterus to
the fallopian tubes where fertilization may be possible.

The uterus is only about three inches long and two inches wide, but
during pregnancy it changes rapidly and dramatically. The top rim of the
uterus is called the fundus and is a landmark for many doctors to track
the progress of a pregnancy. The uterine cavity refers to the fundus of
the uterus and the body of the uterus.

Helping support the uterus are ligaments that attach from the body of
the uterus to the pelvic wall and abdominal wall. During pregnancy the
ligaments prolapse due to the growing uterus, but retract after
childbirth. In some cases after menopause, they may lose elasticity and
uterine prolapse may occur. This can be fixed with surgery.

Some problems of the uterus include uterine fibroids, pelvic pain
(including endometriosis, adenomyosis), pelvic relaxation (or prolapse),
heavy or abnormal menstrual bleeding, and cancer. It is only after all
alternative options have been considered that surgery is recommended in
these cases. This surgery is called hysterectomy. Hysterectomy is the
removal of the uterus, and may include the removal of one or both of the
ovaries. Once performed it is irreversible. After a hysterectomy, many
women begin a form of alternate hormone therapy due to the lack of
ovaries and hormone production.

![](Gray1161.png "Gray1161.png")

### Fallopian Tubes

At the upper corners of the uterus are the **fallopian tubes**. There
are two fallopian tubes, also called the uterine tubes or the oviducts.
Each fallopian tube attaches to a side of the uterus and connects to an
ovary. They are positioned between the ligaments that support the
uterus. The fallopian tubes are about four inches long and about as wide
as a piece of spaghetti. Within each tube is a tiny passageway no wider
than a sewing needle. At the other end of each fallopian tube is a
fringed area that looks like a funnel. This fringed area, called the
infundibulum, lies close to the ovary, but is not attached. The ovaries
alternately release an egg. When an ovary does ovulate, or release an
egg, it is swept into the lumen of the fallopian tube by the fimbriae.

Once the egg is in the fallopian tube, tiny hairs in the tube\'s lining
help push it down the narrow passageway toward the uterus. The oocyte,
or developing egg cell, takes four to five days to travel down the
length of the fallopian tube. If enough sperm are ejaculated during
sexual intercourse and there is an oocyte in the fallopian tube,
fertilization will occur. After fertilization occurs, the zygote, or
fertilized egg, will continue down to the uterus and implant itself in
the uterine wall where it will grow and develop.

If a zygote doesn\'t move down to the uterus and implants itself in the
fallopian tube, it is called a ectopic or tubal pregnancy. If this
occurs, the pregnancy will need to be terminated to prevent permanent
damage to the fallopian tube, possible hemorrhage and possible death of
the mother.

### Mammary glands

!Cross section of the breast of a human
female.{width="200"}
**Mammary glands** are the organs that produce milk for the sustenance
of a baby. These exocrine glands are enlarged and modified sweat glands.

#### Structure

The basic components of the mammary gland are the **alveoli** (hollow
cavities, a few millimetres large) lined with milk-secreting epithelial
cells and surrounded by myoepithelial cells. These alveoli join up to
form groups known as **lobules**, and each lobule has a **lactiferous
duct** that drains into openings in the nipple. The **myoepithelial**
cells can contract, similar to muscle cells, and thereby push the milk
from the alveoli through the lactiferous ducts towards the nipple, where
it collects in widenings (sinuses) of the ducts. A suckling baby
essentially squeezes the milk out of these sinuses.

The development of mammary glands is controlled by hormones. The mammary
glands exist in both sexes, but they are rudimentary until puberty
when - in response to ovarian hormones - they begin to develop in the
female. Estrogen promotes formation, while testosterone inhibits it.

At the time of birth, the baby has lactiferous ducts but no alveoli.
Little branching occurs before puberty when ovarian estrogens stimulate
branching differentiation of the ducts into spherical masses of cells
that will become alveoli. True secretory alveoli only develop in
pregnancy, where rising levels of estrogen and progesterone cause
further branching and differentiation of the duct cells, together with
an increase in adipose tissue and a richer blood flow.

Colostrum is secreted in late pregnancy and for the first few days after
giving birth. True milk secretion (lactation) begins a few days later
due to a reduction in circulating progesterone and the presence of the
hormone prolactin. The suckling of the baby causes the release of the
hormone oxytocin which stimulates contraction of the myoepithelial
cells.

The cells of mammary glands can easily be induced to grow and multiply
by hormones. If this growth runs out of control, cancer results. Almost
all instances of breast cancer originate in the lobules or ducts of the
mammary glands.

  STRUCTURE                 LOCATION & DESCRIPTION                                                                                FUNCTION
  ------------------------- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Breasts                   Upper chest one on each side containing alveolar cells (milk production), myoepithelial cells (contract to expel milk), and duct walls (help with extraction of milk).   Lactation milk/nutrition for newborn.
  Cervix                    The lower narrower portion of the uterus.                                                                                During childbirth, contractions of the uterus will dilate the cervix up to 10 cm in diameter to allow the child to pass through. During orgasm, the cervix convulses and the external os dilates
  Clitoris                  Small erectile organ directly in front of the vestibule.                                                                                Sexual excitation, engorged with blood.
  Fallopian tubes           Extending upper part of the uterus on either side.                                                                                Egg transportation from ovary to uterus (fertilization usually takes place here).
  Hymen                     Thin membrane that partially covers the vagina in young females.
  Labia majora              Outer skin folds that surround the entrance to the vagina.                                                                                Lubrication during mating.
  Labia minora              Inner skin folds that surround the entrance to the vagina.                                                                                Lubrication during mating.
  Mons                      Mound of skin and underlying fatty tissue, central in lower pelvic region
  Ovaries (female gonads)   Pelvic region on either side of the uterus.                                                                                Provides an environment for maturation of oocyte. Synthesizes and secretes sex hormones (estrogen and progesterone).
  Perineum                  Short stretch of skin starting at the bottom of the vulva and extending to the anus.
  Urethra                   Pelvic cavity above bladder, tilted.                                                                                Passage of urine.
  Uterus                    Center of pelvic cavity.                                                                                To house and nourish developing human.
  Vagina                    Canal about 10-8 cm long going from the cervix to the outside of the body.                                                                                Receives penis during mating. Pathway through a womans body for the baby to take during childbirth. Provides the route for the menstrual blood (menses) from the uterus, to leave the body. May hold forms of birth control, such as an IUD, diaphragm, neva ring, or female condom
  Vulva                     Surround entrance to the reproductive tract.(encompasses all external genitalia)
  Endometrium               The innermost layer of uterine wall.                                                                                Contains glands that secrete fluids that bathe the utrine lining.
  Myometrium                Smooth muscle in uterine wall.                                                                                Contracts to help expel the baby.

## The Female Reproductive Cycle

Towards the end of puberty, girls begin to release eggs as part of a
monthly period called the female reproductive cycle, or **menstrual
cycle** (menstrual referring to \"monthly\"). Approximately every 28
days, during ovulation, an ovary sends a tiny egg into one of the
fallopian tubes. Unless the egg is fertilized by a sperm while in the
fallopian in the two to three days following ovulation, the egg dries up
and leaves the body about two weeks later through the vagina. This
process is called menstruation. Blood and tissues from the inner lining
of the uterus (the endometrium) combine to form the menstrual flow,
which generally lasts from four to seven days. The first period is
called **menarche**. During menstruation arteries that supply the lining
of the uterus constrict and capillaries weaken. Blood spilling from the
damaged vessels detaches layers of the lining, not all at once but in
random patches. Endometrium mucus and blood descending from the uterus,
through the liquid creates the menstruation flow. !Menstrual
cycle{width="300"}

The reproductive cycle can be divided into an ovarian cycle and a
uterine cycle (compare ovarian histology and uterine histology in the
diagram on the right). During the **uterine cycle**, the endometrial
lining of the uterus builds up under the influence of increasing levels
of estrogen (labeled as estradiol in the image). Follicles develop, and
within a few days one matures into an **ovum**, or egg. The ovary then
releases this egg, at the time of **ovulation**. After ovulation the
uterine lining enters a secretory phase, or the **ovarian cycle**, in
preparation for implantation, under the influence of progesterone.
Progesterone is produced by the corpus luteum (the follicle after
ovulation) and enriches the uterus with a thick lining of blood vessels
and capillaries so that it can sustain the growing fetus. If
fertilization and implantation occur, the embryo produces Human
Chorionic Gonadotropin (HCG), which maintains the corpus luteum and
causes it to continue producing progesterone until the placenta can take
over production of progesterone. Hence, progesterone is \"pro
gestational\" and maintains the uterine lining during all of pregnancy.
If fertilization and implantation do not occur the corpus luteum
degenerates into a corpus albicans, and progesterone levels fall. This
fall in progesterone levels cause the endometrium lining to break down
and sluff off through the vagina. This is called menstruation, which
marks the low point for estrogen activity and is the starting point of a
new cycle.

Common usage refers to menstruation and menses as a period. This
bleeding serves as a sign that a woman has not become pregnant. However,
this cannot be taken as certainty, as sometimes there is some bleeding
in early pregnancy. During the reproductive years, failure to menstruate
may provide the first indication to a woman that she may have become
pregnant.

Menstruation forms a normal part of a natural cyclic process occurring
in healthy women between puberty and the end of the reproductive years.
The onset of menstruation, known as **menarche**, occurs at an average
age of 12, but is normal anywhere between 8 and 16. Factors such as
heredity, diet, and overall health can accelerate or delay the onset of
menarche.

**Signs of ovulation**

The female body produces outward signs that can be easily recognized at
the time of ovulation. The two main signs are thinning of the cervical
mucus and a slight change in body temperature.

**Thinning of the Cervical Mucus**

After menstruation and right before ovulation, a woman will experience
an increase of cervical mucus. At first, it will be thick and yellowish
in color and will not be very plentiful. Leading up to ovulation, it
will become thinner and clearer. On or around the day of ovulation, the
cervical mucus will be very thin, clear and stretchy. It can be compared
to the consistency of egg whites. This appearance is known as
\'spinnbarkeit\'.

**Temperature Change**

A woman can also tell the time of ovulation by taking her basal body
temperature daily. This is a temperature taken with a very sensitive
thermometer first thing in the morning before the woman gets out of bed.
The temperature is then tracked to show changes. In the uterine cycle, a
normal temperature will be around 97.0 -- 98.0. The day of ovulation the
temperature spikes down, usually into the 96.0 -- 97.0 range and then
the next morning it will spike up to normal of around 98.6 and stay in
that range until menstruation begins.

Both of these methods are used for conception and contraception. They
are more efficient in conception due to the fact that sperm can live for
two to three days inside of the fallopian tubes. A woman could be off by
a couple of days in her calculations and still become pregnant.

**Menopause** is the physiological cessation of menstrual cycles
associated with advancing age. Menopause is sometimes referred to as
\"the change of life\" or climacteric. Menopause occurs as the ovaries
stop producing estrogen, causing the reproductive system to gradually
shut down. As the body adapts to the changing levels of natural
hormones, vasomotor symptoms such as hot flashes and palpitations,
psychological symptoms such as increased depression, anxiety,
irritability, mood swings and lack of concentration, and atrophic
symptoms such as vaginal dryness and urgency of urination appear.
Together with these symptoms, the woman may also have increasingly
scanty and erratic menstrual periods.

Technically, menopause refers to the cessation of menses; the gradual
process through which this occurs, which typically takes a year but may
last as little as six months or more than five years, is known as
climacteric. A natural or physiological menopause is that which occurs
as a part of a woman\'s normal aging process. However, menopause can be
surgically induced by such procedures as hysterectomy.

The average onset of menopause is 50.5 years, but some women enter
menopause at a younger age, especially if they have suffered from cancer
or another serious illness and undergone chemotherapy. Premature
menopause is defined as menopause occurring before the age of 40, and
occurs in 1% of women. Other causes of premature menopause include
autoimmune disorders, thyroid disease, and diabetes mellitus.

Premature menopause is diagnosed by measuring the levels of follicle
stimulating hormone (FSH) and luteinizing hormone (LH). The levels of
these hormones will be higher if menopause has occurred. Rates of
premature menopause have been found to be significantly higher in both
fraternal and identical twins; approximately 5% of twins reach menopause
before the age of 40. The reasons for this are not completely
understood. Post-menopausal women are at increased risk of osteoporosis.

**Perimenopause** refers to the time preceding menopause, during which
the production of hormones such as estrogen and progesterone diminish
and become more irregular. During this period fertility diminishes.
Menopause is arbitrarily defined as a minimum of twelve months without
menstruation. Perimenopause can begin as early as age 35, although it
usually begins much later. It can last for a few months or for several
years. The duration of perimenopause cannot be predicted in advance.

**Premenstrual Syndrome** (PMS) It is common for women to experience
some discomfort in the days leading up to their periods. PMS usually is
at its worst the seven days before a period starts and can continue
through the end of the period. PMS includes both physical and emotional
symptoms: acne, bloating, fatigue, backaches, sore breasts, headaches,
constipation, diarrhea, food cravings, depression, irritability,
difficulty concentrating or handling stress.

## Ovarian and Uterine Cycles in the Nonpregnant Woman

thumb\|An ovary about to release an
egg.

  Ovarian Cycle                  Events                                 Uterine Cycle                     Events
  ------------------------------ -------------------------------------- --------------------------------- -------------------------------------------------
  Follicular phase - Days 1-13   FSH secretion begins.                  Menstruation - Days 2-5           Endometrium breaks down.
                                 Follicle maturation occurs.            Proliferative phase - Days 6-13   Endometrium rebuilds.
                                 Estrogen secretion is prominent.
  Ovulation - Day 14\*           LH spike occurs.
  Luteal phase - Days 15-28      LH secretion continues.                Secretory phase - Days 15-28      Endometrial thickens, and glands are secretory.
                                 Corpus luteum forms.
                                 Progesterone secretion is prominent.

(\*)Assuming a 28 day cycle.

There are two phases of the ovarian cycle the follicular phase and the
luteal phase. In the follicular phase about 10-25 follicles are taken
from preantral or early antrial follicles to develop further. Seven days
later the dominant follicle is selected to develop to full maturity.
This is the pre-cursor for ovulation. Follicles themselves secrete FSH
and estrogen, and these two hormones stimulate follicular growth and
development. Ovulation marks the beginning of the luteal phase. This is
started by the wall of the Graffian follicle to rupture and cause a flow
of antral fluid that will carry the oocyte to the ovary\'s surface. The
ruptured follicle is then turned into a gland (corpus luteum). Which
secretes estrogens and progesterone. This is all triggered by and abrupt
change in plasma LH levels. After ovulation the released oocyte enters
the uterine tube, where it will be either fertilized or discarded.

The uterine cycle operates in sync with the ovarian cycle and is divided
into three phases. The first phase in the menstrual phase. It is named
the menstrual phase because in corresponds with the shedding the uterine
lining or more commonly called menstruation. The corpus luteum
degenerates causing plasma estrogen and progesterone levels to decrease
and in turn causes menstruation. Blood vessels in the outer most layer
of the endometrium constrict and decrease blood flow to the tissues
killing these tissues. After the tissues die they start to separate from
the underlying endometrial tissues. Eventually the dead tissue is shed.
This shedding of the tissues ruptures blood vessels and causes bleeding.
Now we have the proliferative phase. During this phase the uterus renews
itself and prepares for pregnancy. The endometrial tissue that is left
after menstruation begins to grow. The endometrial glands grow and
enlarge causing more blood vessels. The cervical canal has glands that
secrete a thin mucous that helps deposited sperm. Estrogen promotes
uterine changes in this phase. The last phase is the secretory phase.
This is where the endometrium is transformed to make it the best
environment for implantation and subsequent housing and nourishment of
the developing embryo. By doing this the endometrium will do things like
have an enriched blood supply, begin to secrete fluids rich in glycogen,
and even form a plug at the end of the cervical canal so that
microorganisms can not enter. These changes in the uterus are caused by
progesterone, due to the corpus luteum. At the end of the secretory
phase the corpus luteum degenerates, and progesterone levels fall. This
will trigger menstruation.

## Sexual Reproduction

**Sexual reproduction** is a type of reproduction that results in
increasing genetic diversity of the offspring. In sexual reproduction,
genes from two individuals are combined in random ways with each new
generation. Sex hormones released into the body by the endocrine system
signal the body when it is time to start puberty. The female and male
reproductive systems are the only systems so vastly different that each
sex has their own different organs. All other systems have \"unisex\"
organs.

Reproduction is characterized by two processes. The first, meiosis,
involves the halving of the 46 of chromosomes. The second process,
fertilization, leads the fusion of two gametes and the restoration of
the original number of chromosomes: 23 chromosomes from the paternal
side and 23 from the maternal side. During meiosis, the chromosomes of
each pair usually cross over to achieve genetic recombination.

Sexual reproduction cannot happen without the sexual organs called
gonads. Both sexes have gonads: in females, the gonads are the ovaries.
The female gonads produce female gametes (eggs); the male gonads produce
male gametes (sperm). After an egg is fertilized by the sperm, the
fertilized egg is called the zygote.

The fertilization usually occurs in the oviducts, but can happen in the
uterus itself. The zygote then implants itself in the wall of the
uterus, where it begins the processes of embryogenesis and
morphogenesis. The womens body carries out this process of reproduction
for 40 weeks, until delivery of the fetus from the uterus through the
vagina (birth canal). Even after birth, the female continues with the
reproduction process by supplying the milk to nourish the infant.

## Infertility

**Infertility** is the inability to naturally conceive a child or the
inability to carry a pregnancy to term. There are many reasons why a
couple may not be able to conceive without medical assistance.
Infertility affects approximately 15% of couples. Roughly 40% of cases
involve a male contribution or factor, 40% involve a female factor, and
the remaining 20% involve both sexes. Healthy couples in their mid-20s
having regular sex have a one-in-four chance of getting pregnant in any
given month. This is called \"Fecundity\".

### Primary vs. secondary

According to the American Society for Reproductive Medicine, infertility
affects about 6.1 million people in the United States, equivalent to 10%
of the reproductive age population. Female infertility accounts for one
third of infertility cases, male infertility for another third, combined
male and female infertility for another 15%, and the remainder of cases
are \"unexplained\'\'.

\"Secondary infertility\" is difficulty conceiving after already having
conceived and carried a normal pregnancy. Apart from various medical
conditions (e.g. hormonal), this may come as a result of age and stress
felt to provide a sibling for their first child. Technically, secondary
infertility is not present if there has been a change of partners.

### Factors of Infertility

Factors relating to female infertility are:

-   General factors
    -   Diabetes mellitus,thyroid disorders,adrenal disease
    -   Significant liver,kidney disease
    -   Psychological factors
-   Hypothalamic-pituitary factors:
    -   Kallmann syndrome
    -   Hypothalamic dysfunction
    -   Hyperprolactinemia
    -   Hypopituitarism
-   Ovarian factors
    -   Polycystic ovary syndrome
    -   Anovulation
    -   Diminished ovarian reserve
    -   Luteal dysfunction
    -   Premature menopause
    -   Gonadal dysgenesis (Turner syndrome)
    -   Ovarian neoplasm
-   Tubal/peritoneal factors
    -   Endometriosis
    -   Pelvic adhesions
    -   Pelvic inflammatory disease(PID, usually due to chlamydia)
    -   Tubal occlusion
-   Uterine factors
    -   Uterine malformations
    -   Uterine fibroids (leiomyoma)
    -   Asherman\'s Syndrome
-   Cervical factors
    -   Cervical stenosis
    -   Antisperm antibodies
    -   Insufficient cervical mucus (for the travel and survival of
        sperm)
-   Vaginal factors
    -   Vaginismus
    -   Vaginal obstruction
-   Genetic factors
    -   Various intersexuality\|intersexed conditions, such as androgen
        insensitivity syndrome

### Combined Infertility

In some cases, both the man and woman may be infertile or sub-fertile,
and the couple\'s infertility arises from the combination of these
factors. In other cases, the cause is suspected to be immunological or
genetic; it may be that each partner is independently fertile but the
couple cannot conceive together without assistance.

### Unexplained Infertility

In about 15% of cases of infertility, investigation will show no
abnormalities. In these cases abnormalities are likely to be present but
not detected by current methods. Possible problems could be that the egg
is not released at the optimum time for fertilization, that it may not
enter the fallopian tube, sperm may not be able to reach the egg,
fertilization may fail to occur, transport of the zygote may be
disturbed, or implantation fails. It is increasingly recognized that egg
quality is of critical importance.

### Diagnosis of Infertility

Diagnosis of infertility begins with a medical history and physical
exam. The healthcare provider may order tests, including the following:

-   an endometrial biopsy, which tests the lining of the uterus
-   hormone testing, to measure levels of female hormones
-   laparoscopy, which allows the provider to see the pelvic organs
-   ovulation testing, which detects the release of an egg from the
    ovary
-   Pap smear, to check for signs of infection
-   pelvic exam, to look for abnormalities or infection
-   a postcoital test, which is done after sex to check for problems
    with secretions
-   special X-ray tests

### Treatment

-   Fertility medication which stimulates the ovaries to \"ripen\" and
    release eggs (e.g. Clomifene\|clomifene citrate, which stimulates
    ovulation)
-   Surgery to restore potency of obstructed fallopian tubes
    (tuboplasty)
-   Donor insemination which involves the woman being artificially
    inseminated or artificially inseminated with donor sperm.
-   In vitro fertilization (IVF) in which eggs are removed from the
    woman, fertilized and then placed in the woman\'s uterus, bypassing
    the fallopian tubes. Variations on IVF include:
    -   Use of donor eggs and/or sperm in IVF. This happens when a
        couple\'s eggs and/or sperm are unusable, or to avoid passing on
        a genetic disease.
    -   Intracytoplasmic sperm injection (ICSI) in which a single sperm
        is injected directly into an egg; the fertilized egg is then
        placed in the woman\'s uterus as in IVF.
    -   Zygote intrafallopian transfer(ZIFT) in which eggs are removed
        from the woman, fertilized and then placed in the woman\'s
        fallopian tubes rather than the uterus.
    -   Gamete intrafallopian transfer(GIFT) in which eggs are removed
        from the woman, and placed in one of the fallopian tubes, along
        with the man\'s sperm. This allows fertilization to take place
        inside the woman\'s body.
-   Other assisted reproductive technology (ART):
    -   Assisted hatching
    -   Fertility preservation
    -   Freezing (cryopreservation) of sperm, eggs, & reproductive
        tissue
    -   Frozen embryo transfer (FET)
-   Alternative and complimentary treatments
    -   Acupuncture Recent controlled trials published in Fertility and
        Sterility have shown acupuncture to increase the success rate of
        IVF by as much as 60%. Acupuncture was also reported to be
        effective in the treatment of female anovular infertility, World
        Health Organization, Acupuncture: Review and Analysis of Reports
        on Controlled Trials (2002).
    -   Diet and supplements
    -   Healthy lifestyle

## Types of Birth Control

**Birth control** is a regimen of one or more actions, devices, or
medications followed in order to deliberately prevent or reduce the
likelihood of a woman becoming pregnant. Methods and intentions
typically termed birth control may be considered a pivotal ingredient to
family planning. Mechanisms which are intended to reduce the likelihood
of the fertilization of an ovum by a sperm may more specifically be
referred to as contraception. Contraception differs from abortion in
that the former prevents fertilization, while the latter terminates an
already established pregnancy. Methods of birth control (e.g. the pill,
IUDs, implants, patches, injections, vaginal ring and some others) which
may prevent the implantation of an embryo if fertilization occurs are
medically considered to be contraception. It is advised to talk with a
doctor before choosing a contraceptive. If you have genetics problems or
blood conditions, such as factor V leiden, certain contraceptives can be
deadly.

  Type                                 Procedure                                                                                Method                                                                                Effectiveness                Risks
  ------------------------------------ --------------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------- -------------------------------------------
  Abstinence                           Refrain from sexual intercourse                                                                                No sperm in vagina                                                                                100%                         None
  Rhythm Method                        Intercourse is avoided for about an 8-day span every month in middle of her cycle, from about five days before ovulation to three days after ovulation.   fertilization is only possible during 8-day span in middle of menstrual cycle                                                                                70-80%                       None
  Withdrawal                           The man withdraws his penis from the vagina at just the right moment before ejaculation.                                                                  sperm are unable to enter vagina if male penis is removed at the right time                                                                                70-80%                       None
  Tubal Ligation (Vasectomy)           Oviducts are cut and tied                                                                                No eggs in oviduct                                                                                Almost 99%                   About 75% Irreversible
  Hormonal IUD (intrauterine device)   Flexible, plastic coil inserted by physician                                                                                Releases small amounts of estrogen. In most cases, stops egg from developing and being released, but can also operate by killing a fertilized egg by preventing its implantation   About 99%                    May cause infections, uterine perforation
  Oral Contraceptive                   Hormone medication taken daily                                                                                Stops release of FSH and LH, but can also operate by killing a fertilized egg by preventing its implantation                                                                       More than 90%                Blood clots, especially in smokers
  Contraceptive Implants               Tubes of progesterone implanted under the skin                                                                                Stops release of FSH and LH, but can also operate by killing a fertilized egg by preventing its implantation                                                                       More than 90%                None known
  Contraceptive Injections             Injections of hormones                                                                                Stops release of FSH and LH, but can also operate by killing a fertilized egg by preventing its implantation                                                                       About 99%                    Possible osteoporosis
  Diaphragm                            Latex cup inserted into vagina to cover cervix before intercourse                                                                                Blocks entrance of sperm into uterus                                                                                With spermicide, about 90%   Latex or spermicide allergy
  Cervical Cap                         Latex cup held by suction over cervix                                                                                Delivers spermicide near cervix                                                                                Almost 85%                   UTI, latex or spermicide allergy
  Female Condom                        Polyurethane liner fitted inside vagina                                                                                Blocks entrance of sperm into uterus and prevents STD's                                                                                Almost 85%                   None
  Male Condom                          soft sheath, made of latex or animal membrane, encloses penis, trapping ejaculated sperm                                                                  Blocks entrance of sperm into vagina and prevents STD\'s                                                                                90%                          None
  Jellies, Cream, Foams                Spermicidal products inserted before intercourse                                                                                Kills large number of sperm                                                                                About 75%                    UTI, allergy to spermicides
  Natural Family Planning              Keep record of ovulation using various methods                                                                                Avoid sexual intercourse near ovulation                                                                                About 70%                    None known
  Douche                               Vagina cleansed after intercourse                                                                                Washes out sperm                                                                                Less than 70%                None known
  Plan B Pill                          Pill taken after intercourse                                                                                Prevents release of egg, fertilization of egg, but can also operate by killing a fertilized egg by preventing its implantation                                                     About 89%                    Same as oral contraceptive

## Sexually Transmitted Diseases

**Sexually transmitted diseases** (STDs) are diseases or infections
likely to be transmitted by sexual contact: vaginal intercourse, oral
sex, and/or anal sex. Many STDs are (more easily) transmitted through
the mucous membranes of the penis, vulva, and (less often) the mouth.
The visible membrane covering the head of the penis is a mucous
membrane, though, for those who are circumcised it is usually dry and
produces no mucus (similar to the lips of the mouth). Mucous membranes
differ from skin in that they allow certain pathogens (viruses or
bacteria) into the body (more easily).

The probability of transmitting infections through sex is far greater
than by more casual means of transmission, such as non-sexual
contact---touching, sharing cutlery, and shaking hands. Although mucous
membranes exist in the mouth as well as in the genitals, many STDs are
more likely to be transmitted through oral sex than through deep
kissing. Many infections that are easily transmitted from the mouth to
the genitals or from the genitals to the mouth, are much harder to
transmit from one mouth to another. With HIV, genital fluids happen to
contain a great deal more of the pathogen than saliva. Some infections
labeled as STDs can be transmitted by direct skin contact. Herpes
simplex and HPV are both examples. Depending on the STD, a person who
has the disease but has no symptoms may or may not be able to spread the
infection. For example, a person is much more likely to spread herpes
infection when blisters are present than when they are absent. However,
a person can spread HIV infection at any time, even if he/she has not
developed symptoms of AIDS.

All sexual behaviors that involve contact with the bodily fluids of
another person should be considered to hold some risk of transmission of
sexually transmitted diseases. Most attention has focused on controlling
HIV, which causes AIDS, but each STD presents a different situation.

As may be noted from the name, sexually transmitted diseases are
transmitted from one person to another by certain sexual activities
rather than being actually caused by those sexual activities. Bacteria,
fungi, protozoa or viruses are still the causative agents. It is not
possible to catch any sexually transmitted disease from a sexual
activity with a person who is not carrying a disease; conversely, a
person who has an STD received it from contact (sexual or otherwise)
with someone who is infected.

Although the likelihood of transmitting diseases by sexual activities
varies a great deal, in general, all sexual activities between two (or
more) people should be considered as being a two-way route for the
transmission of STDs (i.e. \"giving\" or \"receiving\" are both risky).

### Prevention of Sexually Transmitted Diseases

Although healthcare professionals suggest that safer sex, such as the
use of condoms, as the most reliable way of decreasing the risk of
contracting sexually transmitted diseases during sexual activity, safer
sex should by no means be considered an absolute safeguard. The transfer
of and exposure to bodily fluids, such as blood transfusions and other
blood products, sharing injection needles, needle-stick injuries (when
medical staff are inadvertently jabbed or pricked with needles during
medical procedures), sharing tattoo needles, and childbirth are all
avenues of transmission. These means put certain groups, such as
doctors, haemophiliacs and drug users, particularly at risk.

### **Human Papillomavirus (HPV)**

There are over 100 types of this virus which is often asymptomatic.
Nearly 3 out of 4 Americans between ages 15 and 49 have been infected.
It can be contracted through one partner and remain dormant allowing it
to be transmitted to another. Some types can cause cervical cancer.

Genital HPV infection is a sexually transmitted disease that is caused
by human papillomavirus. Human papillomavirus is the name of a group of
viruses that includes more than 100 different strains. More than 30 of
these are sexually transmitted and they can infect the genital area of
men and women. Approximately 20 million people are currently infected
with HPV and at least 50% of sexually active men and women will acquire
HPV at some point in their lives. By age 50 at least 80% of women will
have acquired HPV and about 6.2 million Americans get a new HPV
infection each year. Most people who have HPV don\'t know that they are
infected. The virus lives in the skin or mucous membranes and usually
causes no symptoms. Commonly some people get visible genital warts or
have pre-cancerous changes in the cervix, vulva, anus, or penis. Very
rarely, HPV results in anal or genital cancers. Genital warts usually
appear soft, moist, pink, or flesh colored swellings. They can be
raised, flat, single, or multiple, small or large and sometimes
cauliflower shaped. Warts may not appear for weeks or months or not at
all and the only way to diagnose them is by visible inspection. Most
women are diagnosed with HPV on the basis of abnormal pap tests and
there are no tests available for men. There is no cure for HPV. The
surest way to eliminate risk for HPV is to refrain from any genital
contact with another individual. For those who choose to be sexually
active, a long term monogamous relationship with an uninfected partner
is the strategy most likely to prevent future HPV infections.The next
best way to help reduce risk is using a condom but the effectiveness is
unknown.

**What is the connection between HPV and cervical cancer?** All types of
HPV cause mild pap test abnormalities which do not have serious
consequences. Approximately 10 of the 30 identified HPV types can lead
to development of cervical cancer. Research as shown that for most
women, 90% cervical HPV infection becomes undetectable within two years.
Although only a small proportion of women have persistent infection,
persistent infection with the high risk types of HPV is the main risk
factor for cervical cancer.

A pap test can detect pre-cancerous and cancerous cells on the cervix.
Regular pap testing and careful medical follow up, with treatment if
necessary, can help ensure that pre-cancerous changes in the cervix
caused by HPV infection do not develop into life-threatening cervical
cancer. The pap test used in the U.S. cervical cancer screening programs
is responsible for greatly reducing deaths from cervical cancer.

## **Diseases and Disorders of the Female Reproductive System**

Women are commonly dealing with many different diseases and disorders
that pertain to the reproductive system. Here are some of the most
common:

1.  **Vulvovaginitis** (pronounced:vul-vo-vah-juh-ni-tus) is an
    inflammation of the vulva and vagina. It may be caused by irritating
    substances such as laundry soap, bubble baths or poor hygiene such
    as wiping from back to front. Symptoms include redness and itching
    in these areas and sometimes vaginal discharge. It can also be
    caused by an overgrowth of candida, a fungus normally present in the
    vagina.
2.  **Nonmenstrual vaginal bleeding** is most commonly due to the
    presence of a foreign body in the vagina. It may also be due to
    urethral prolapse, a condition in which the mucous membranes of the
    urethra protrude into the vagina and forms a tiny, donut shaped mass
    of tissue that bleeds easily. It can also be due to a straddle
    injury or vaginal trauma from sexual abuse.
3.  **Ectopic Pregnancy** occurs when a fertilized egg or zygote
    doesn\'t travel into the uterus, but instead grows rapidly in the
    fallopian tube. Women with this condition can develop severe
    abdominal pain and should see a doctor because surgery may be
    necessary.
4.  **Ovarian tumors**,although rare, can occur. Women with ovarian
    tumors may have abdominal pain and masses that can be felt in the
    abdomen. Surgery may be needed to remove the tumor.
5.  **Ovarian cysts** are noncancerous sacs filled with fluid or
    semi-solid material. Although they are common and generally
    harmless, they can become a problem if they grow very large. Large
    cysts may push on surrounding organs, causing abdominal pain. In
    most cases, cysts will pass or disappear on their own and treatment
    is not necessary. If the cysts are painful and occur frequently, a
    doctor may prescribe birth control pills to alter their growth and
    occurrences. Surgery is also an option if they need to be removed.
6.  **Polycystic ovary syndrome** is a hormone disorder in which too
    many hormones are produced by the ovaries. This condition causes the
    ovaries to become enlarged and develop many fluid filled sacs or
    cysts. It often first appears during the teen years. Depending on
    the type and the severity of the condition, it may be treated with
    drugs to regulate hormone balance and menstruation.
7.  **Trichomonas vaginalis** inflammatory condition of the vagina
    usually a bacterial infection also called vaginosis.
8.  **Dysmenorrhea** is painful periods.
9.  **Menorrhagia** is when a woman has very heavy periods with excess
    bleeding.
10. **Oligomenorrhea** is when a woman misses or has infrequent periods,
    even though she has been menstruating for a while and is not
    pregnant.
11. **Amenorrhea** is when a girl has not started her period by the time
    she is 16 years old or 3 years after puberty has started, has not
    developed signs of puberty by 14, or has had normal periods but has
    stopped menstruating for some reasons other than pregnancy.
12. **Toxic shock syndrome** is caused by toxins released into the body
    during a type of bacterial infection that is more likely to develop
    if a tampon is left in too long. It can produce high fever,
    diarrhea, vomiting, and shock.
13. **Candidasis** symptoms of yeast infections include itching, burning
    and discharge. Yeast organisms are always present in all people, but
    are usually prevented from \"overgrowth\" (uncontrolled
    multiplication resulting in symptoms) by naturally occurring
    microorganisms.

At least three quarters of all women will experience candidiasis at some
point in their lives. The Candida albicans organism is found in the
vaginas of almost all women and normally causes no problems. However,
when it gets out of balance with the other \"normal flora,\" such as
lactobacilli (which can also be harmed by using douches), an overgrowth
of yeast can result in noticeable symptoms. Pregnancy, the use of oral
contraceptives, engaging in vaginal sex after anal sex in an unhygienic
manner, and using lubricants containing glycerin have been found to be
causally related to yeast infections. Diabetes mellitus and the use of
antibiotics are also linked to an increased incidence of yeast
infections. Candidiasis can be sexually transmitted between partners.
Diet has been found to be the cause in some animals. Hormone Replacement
Therapy and Infertility Treatment may be factors.

There are also cancer\'s of the female reproductive system, such as:

1.  Cervical cancer
2.  Ovarian cancer
3.  Uterine cancer
4.  Breast cancer

**Endometriosis**

Endometriosis is the most common gynecological diseases, affecting more
than 5.5 million women in North America alone! The two most common
symptoms are pain and infertility. In this disease a specialized type of
tissue that normally lines the inside of the uterus,(the endometrium)
becomes implanted outside the uterus, most commonly on the fallopian
tubes, ovaries, or the tissue lining the pelvis. During the menstrual
cycle, hormones signal the lining of the uterus to thicken to prepare
for possible pregnancy. If a pregnancy doesn\'t occur, the hormone
levels decrease, causing the thickened lining to shed.

When endometrial tissue is located in other parts it continues to act in
it\'s normal way: It thickens, breaks down and bleeds each month as the
hormone levels rise and fall. However, because there\'s nowhere for the
blood from this mislocated tissue to exit the body, it becomes trapped
and surrounding tissue becomes irritated. Trapped blood may lead to
growth of cysts. Cysts in turn may form scar tissue and adhesions. This
causes pain in the area of the misplaced tissue, usually the pelvis.
Endometriosis can cause fertility problems. In fact, scars and adhesions
on the ovaries or fallopian tubes can prevent pregnancy. Endometriosis
can be mild, moderate or severe and tends to get worse over time without
treatment. The most common symptoms are:

1.  **Painful periods** Pelvic pain and severe cramping, intense back
    pain and abdominal pain.
2.  **Pain at other times** Women may experience pelvic pain during
    ovulation, sharp deep pain in pelvis during intercourse, or pain
    during bowel movements or urination.
3.  **Excessive bleeding** Heavy periods or bleeding between periods.
4.  **Infertility** Approximately 30-40% of women

The cause of endometriosis remains mysterious. Scientists are studying
the roles that hormones and the immune system play in this condition.
One theory holds that menstrual blood containing endometrial cells flows
back through the fallopian tubes, takes root and grows. Another
hypothesis proposes that the bloodstream carries endometrial cells to
other sites in the body. Still another theory speculates that a
predisposition toward endometriosis may be carried in the genes of
certain families.

Other researchers believe that certain cells present within the abdomen
in some women retain their ability to specialize into endometrial cells.
These same cells were responsible for the growth of the woman\'s
reproductive organs when she was an embryo. It is believed that genetic
or environmental influences in later life allow these cells to give rise
to endometrial tissue outside the uterus.

Experts estimate that up to one in ten American women of childbearing
age have endometriosis. There is some thinking that previous damage to
cells that line the pelvis can lead to endometriosis. There are several
ways to diagnose endometriosis:

1.  **Pelvic exam**
2.  **Ultrasound**
3.  **Laparoscopy** Usually used, most correct diagnosis
4.  **Blood test**

Endometriosis can be treated with:

1.  **Pain medication**
2.  **Hormone therapy**
    1.  **Oral contraceptives**
    2.  **Gonadotropin-releasing hormone(Gn-Rh)agonists and
        antagonists**
    3.  **Danazol(Danocrine)**
    4.  **Medroxyprogesterone(Depo-Provera)**
3.  **Conservative surgery** which removes endometrial growths.
4.  **Hysterectomy**

## Check Your Understanding

Answers for these questions can be found here

1\. In homology, the \_\_\_\_\_\_\_\_\_\_\_ in the female is equal to
the penis in the male

:   A\) labia majora
:   B\) clitoral hood
:   C\) clitoris
:   D\) labia minora
:   E\) none of the above

2\. This contains some of the strongest muscles in the human body

:   A\) uterus
:   B\) clitoris
:   C\) cervix
:   D\) labia majora

3\. This protects the vaginal and urethral openings

:   A\) labia majora
:   B\) labia minora
:   C\) clitoris
:   D\) urethra

4\. Sally has noticed that her cervical mucus has changed and now
resembles egg whites- from this Sally could assume

:   A\) her period will begin soon
:   B\) nothing, this is a normal occurrence
:   C\) she has a yeast infection
:   D\) she is ovulating

5\. Debbie recently went to the OBGYN and was diagnosed with PCOD
(polycystic ovary syndrome) because of this she has

:   A\) nothing, its normal in women
:   B\) antisperm antibodies
:   C\) an overproduction of LH
:   D\) leaking of milk from her mammary glands
:   E\) problems becoming pregnant

6\. Angie went to the doctor because she has had pain in her leg
recently- this could be caused by

:   A\) ovulation pain
:   B\) her period that will be starting tomorrow
:   C\) premenstrual syndrome
:   D\) a blood clot resulting from her birth control pill

7\. Sue recently started her period and has noticed that they are very
heavy and painful, and that they are inconsistent in their timing. One
explanation could be

:   A\) endometriosis
:   B\) ovarian cancer
:   C\) candidiasis
:   D\) toxic shock syndrome
:   E\) amenorrhea

8\. Mary is getting married and is not ready to become a mother- she
chooses this birth control because of its high effectiveness

:   A\) natural family planning
:   B\) a diaphragm
:   C\) contraceptive injections
:   D\) a spermicide foam

9\. The release of LH in woman causes

:   A\) menstration
:   B\) ovulation
:   C\) increase of endometrial lining
:   D\) decrease of endometrial lining
:   E\) nothing LH only does something in the male reproductive system

10\. When the ovaries stop producing estrogen, this occurs

:   A\) ovulation
:   B\) implantation
:   C\) premenstrual syndrome
:   D\) menopause

11\. Infertility affects what percentage of couples?

:   A\) 5%
:   B\) 10%
:   C\) 15%
:   D\) 20%

12\. What is the only 100% effective form of birth control?

:   A\) Tubal ligation
:   B\) IUD
:   C\) Natural family planning
:   D\) Abstinence

## Glossary

**Adhesions**: Abnormal tissue that binds organs together

**Alveoli**: Basic components of the mammary glands; lined with
milk-secreting epithelial cells

**Birth Control**: regimen of one or more actions, devices, or
medications followed in order to deliberately prevent or reduce the
likelihood of a woman becoming pregnant

**Cervical Mucus**: Mucus secreted by the cervix, near ovulation it
helps to lower the acidity of the vagina

**Cervix**: Lower, narrow portion of the uterus where it joins with the
top of the vagina

**Clitoris**: Small body of spongy tissue that functions solely for
sexual pleasure

**Chromosomes**: Structures in the nucleus that contain the genes for
genetic expression

**Ectocervix**: Portion of the cervix projecting into vagina

**Endocervical Canal**: Passageway between the external os and the
uterine cavity

**Endometrium**: The inner lining of the uterus

**Fallopian Tubes**: Located at the upper end of the vagina, passage way
for the egg from the ovary

**Factor V Leiden**: This is the name given to a variant of human factor
V that causes a hypercoagulability disorder. In this disorder the Leiden
variant of factor V, cannot be inactivated by activated protein C.
Factor V Leiden is the most common hereditary hypercoagulability
disorder amongst Eurasians. It is named after the city Leiden (The
Netherlands), where it was first identified in 1994 by Prof R. Bertina
et al.

**Gamete**: A haploid sex cell; either an egg cell or a sperm cell

**Gene**: That portion of the DNA of a chromosome containing the
information needed to synthesize a particular protein molecule

**Gonad**: A reproductive organ, testis or ovary that produces gametes
and sex hormones

**Hormone**: A chemical substance produced in an endocrine gland and
secreted into the bloodstream that acts on target cells to produce a
specific effect

**Hymen**: Thin fold of mucous membrane that separates the lumen of the
vagina from the urethral sinus

**Infertility**: Inability to naturally conceive a child or the
inability to carry a pregnancy to term

**Labia Majora**: Outer \"lips\" of the vulva, made of loose connective
tissue and adipose tissue with some smooth muscle

**Labia Minora**: Inner lips of the vulva, folds and protects the
vagina, urethra and clitoris

**Mammary Glands**: Organs that produce milk for the sustenance of a
baby

**Meiosis**: A specialized type of cell division by which gametes, or
haploid sex cells, are formed

**Menarche**: The first menstrual discharge; occurs normally between the
ages of 9 and 17

**Menopause**: The period marked by the cessation of menstrual periods
in the human female

**Menstrual Cycle**: The rhythmic female reproductive cycle
characterized by physical changes in the uterine lining

**Menstruation**: The discharge of blood and tissue from the uterus at
the end of menstrual cycle

**Mittelschmerz**: Pain near the lower abdomen site at the time of
ovulation; German for ovulation pain

**Mons Veneris**: soft mound at the front of the vulva (fatty tissue
covering the pubic bone)

**Ovarian Cycle**: Last phase of the reproductive cycle; if no
implantation occurs, causes the breakdown of the endometrial lining and
causes menstruation

**Ovulation**: The rupture of an ovarian follicle with the release of an
ovum

**Perineum**: External region between the scrotum and the anus in a male
or between the vulva and anus in a female

**Premenstrual Syndrome (PMS)**: Time leading up to menstruation;
includes both physical and emotional symptoms: acne, bloating, fatigue,
backaches, sore breasts, headaches, constipation, diarrhea, food
cravings, depression, irritability, difficulty concentrating or handling
stress

**Puberty**: The period of development in which the reproductive organs
become functional and the secondary sex characteristics are expressed

**Reproduction**: Process by which an organism continues its species

**Sexually transmitted diseases (STDs)**: diseases or infections that
have a significant probability of transmission between humans by means
of sexual contact

**Urethra**: Located below the clitoris, used for the passage of urine

**Uterine Cycle**: First part of the reproductive cycle; the time when
the endrometrial lining builds up and follicles develop

**Uterus**: Major reproductive organ, receives fertilized eggs which
become implanted in the lining, the lining (endometrium) provides
nourishment to developing fetus; contains some of the strongest muscles
in the female body and is able to stretch during fetus development

**Vagina**: Muscular, hollow tube that extends from the vaginal opening
to the cervix

**Vulva**: External female genitals, includes labia majora, labia
minora, mons pubis, clitoris, meatus, vaginal vestibule, vestibule bulbs
and vestibular glands

## References

-   Essentials of Anatomy and Physiology. Fourth Edition. Valerie C.
    Scanlon and Tina Sanders.
-   Human Anatomy. Sixth Edition. Van De Graaff.
-   Wikibook: Sexual Health
-   <http://www.fda.gov/cder/drug/infopage/planBQandAhtm>
-   <http://www.goplanb.com/Forconsumers>
-   American Social Health Association;ashastd.org
-   <http://www.cdc.gov>
-   <http://www.mayoclinic.com>