Ovary: produce female eggs/ovum and female hormones (estrogen, progesterone)

Ovum: female reproductive cells that contribute X chromosomes.

Fallopian tubes: tubes that transport ovum to the uterus; passageway where fertilization occurs; site of ectopic pregnancy; site where tubal ligation (sterilization) occurs.

Uterus: also known as the “womb” when an egg is fertilized and implants in the lining of the uterus; when no fertilized egg is present the lining of the uterus sheds for the menstrual cycle.

Cervix: lower end of the uterus; an opening between the uterus and vagina that passes sperm, menstrual fluid, and a fetus.

Vagina: pathway for menstrual flow, birth canal, sperm, and STIs. Opening for sexual intercourse and contains vaginal secretions/lubrication.

Urethra: opening for urine.

Clitoris: sensitive tissue with sole purpose for sexual stimulation.

Passageway of Ovum:
Ovary - Fallopian tube - Uterus - Cervical Opening - Vagina

At the time the ovaries are formed in the fetus, there are approximately 6000000 primordial follicles, which decrease to about 600000 at birth, to 300000 at the first menstrual cycle, to about 10000 at the time of menopause.

The Cycle
- The average cycle is 28 days and has two distinct phases

The Follicular Phase
- The follicular phase starts on day one of the menstrual cycle (the first full day of bleeding)
- The hypothalamus in the brain releases gonadotropin-releasing hormone (GnRH)
- GnRH signals the pituitary gland to release follicle stimulating hormone (FSH)
- FSH stimulates the eggs inside the ovaries to grow
- About 20 immature eggs response and begin to develop within sacs known as follicles
- Follicles provide nourishment to the eggs
- As the eggs develop, the ovaries release estrogen.
- Estrogen signals the pituitary gland to reduce FSH production
- Only enough RSH is now released to stimulate one egg to continue developing, the rest of the eggs shrivel away.
- Estrogen stimulates the lining of the uterus to thicken
- The primary follicle contains the contains the egg that has grown the most rapidly.
- Estrogen continues to rise until it triggers a surge of luteinizing hormone (LH) from the pituitary gland
- LH stimulates ovualtion
- The follicle ruptures and the egg is released along with the follicular fluid onto the surface of the ovary.

The Luteal Phase
- The ruptured follicle continues to receive LH
- The LH enables the follicle to turn into a small cyst known as the corpus luteum
- The corpus luteum produces progesterone
- Progesterone

1) builds and thickens the endometrium, developing glandular structures and blood vessels that supply nutrients to the developing embryo
2) it switches off FSH an LH
3) it raises the basal body temperature (BBT) by half a degree, warming the uterus and fertilized egg.

The Journey of the Egg
- The egg is surrounded by the zona pellucida, a protective shell
- The shell is surrounded by a mass of sticky cells called the cumulus oophorus
- These sticky cells allow the finger like projections (fimbriae) at the end of each fallopian tube, to pick up the egg and sweep it into the tube
- The channel from the fimbriae to the uterus is lined with cilia, which together with muscular contractions move the ovum along the tube to the uterus.
- The journey from the ovary to the uterus take about 6 days
- If the egg is not fertilized it will disintegrate and is absorbed

- the genetic material from a sperm cell (spermatozoon) and secondary oocyte merge into a single nucleus
- fertilization normally occurs in the Fallopian tube 12-24 hours after ovulation
- ejaculated sperm can remain viable for about 48 hours and a secondary oocyte is viable for about 24 hours after ovulation
- peristaltic contractions and the action from the cilia transport the oocyte through the tube
- sperm swim to the oocyte by whip-like movements from its tail
- sperm produce an enzyme (acrosin) that stimulates sperm motility and migration
- uterine contractions stimulated by the prostaglandins in semen aids sperm movement
- sperm undergo functional changes (capacitation) in the female reproductive tract: the membrane around the acrosome becomes fragile so that several destructive enzymes are released
- the enzymes help penetrate the ring of cells (corona radiate) that surround the oocyte
- one sperm penetrates and enters a secondary oocyte, this is called syngamy
- syngamy causes depolarization, which triggers the release of calcium ions into the cell
- calcium ions stimulate the release of granules, that in turn, promote change changes in the zona pelllucida to block entry of the other sperm
- oocyte completes equatorial division (meiosis ll)
- the nucleus from the sperms head and the nucleus from the ovum fuse to produce segmentation nucleus
- the segmentation nucleus contains 23 chromosomes from the male pronucleus and 23 chromosomes from the female pronucleus
- the fertilized ovum is now called a zygote
- rapid mitotic cell divisions of the zygote are called cleavage
- cleavage is completed 30 hours after fertilization
- successive cleavages produce a solid sphere of cells called morula
- the morula is the same size as the original zygote
- at 4 1/2 - 5 days, the dense cluster of cells has developed into a hollow ball of cells and enters the uterine cavity, it is now called a blastocyst

The testes (gonads) are the primary reproductive organ in the male. They produce sperm (exocrine function) and testosterone (endocrine function). The accessory reproductive structures are ducts or glands that aid in the delivery of sperm to the body exterior or to the female reproductive tract.

Testes are approx. 4cm long and 2.5cm wide. A fibrous connective tissue capsule, the tunica albuginea (white coat) surrounds each testis. Extensions of this capsule (septa) plunge into the testis and divide it into a large number of lobules. Each lobule contains one to four tightly coiled seminiferous tubules, the actual 'sperm producing site'. Seminiferous tubules of each lobe empty sperm into another set of tubules, the rete testis, located at one side of the testis. Sperm travel through the rete testis to enter the first part of the duct system, the epididymis, which hugs the external surface of the testis.

Lying in the soft connective tissue surrounding the seminiferous tubules are the interstitial cells, functionally distinct cells that produce androgens, most importantly testosterone.

The parts that transport sperm from the body are the epididymis, ductus deferens, and urethra.

The comma-shaped epididymis is a highly coiled tube about 6 meters long that caps the superior part of the testis and then runs down its posterolateral side. The epididymis is the first part of the male duct system and provides a temporary storage site for the immature sperm that enter it from the testis. While the sperm make their way along the twisted course of the epididymis (about 20 days), they mature, gaining the ability to swim. When a male is sexually stimulated, the walls of the epididymis contract to expel the sperm into the next part of the duct system, the ductus deferens.

The ductus deferens, or, vas deferens, runs upward from the epididymis through the inguinal canal into the pelvic cavity and arches over the superior aspect of the bladder. This tube is enclosed, along with blood vessels and nerves, in a connective tissue sheath called the spermatic cord. The end of the vas deferens empties into the ejaculatory duct, which passes through the prostate gland to merge with the urethra. The main function of the ductus deferens is to propel live sperm from their storage sites, the epididymis and distal part of the ductus deferens, into the urethra. At the moment of ejaculation, the thick layers of smooth muscle in its walls create peristaltic waves that rapidly squeeze the sperm forward.

Part of the ductus deferens is in the scrotal sac which hangs outside the body cavity. Some men voluntarily have a vasectomy. This entales a surgeon making a small incision into the scrotum and then cutting or cauterizing the vas deferens. Sperm is still produced, but they can no longer reach the outside of the body, they eventually deteriorate and are reabsorbed. The man is then sterile. Testosterone is still produced so libido and secondary sex characteristics are retained.

The urethra, which extends from the base of the bladder to the tip of the penis, is the terminal part of the male duct system. It has 3 main regions, the prostatic urethra (surrounded by the prostate gland), the membranous urethra (from the prostate to the penis), and the spongy urethra (runs the length of the penis). The urethra carries both urine and sperm to the body exterior, thus it is part of both the reproductive and urinary systems. However, urine and sperm never pass at the same time. When ejaculation occurs and sperm enter the prostatic urethra from the ejaculatory ducts, the bladder sphincter constricts. This event not only prevents the passage of urine into the urethra, but also prevents sperm from entering the urinary bladder.

The accessory glands include the seminal vesicles, the prostate gland, and the bulbourethral glands. These produce most of the semen, the fluid that contains the sperm within that is propelled out of the male's reproductive tract during ejaculation.

These are located at the base of the bladder. They produce about 60% of the fluid volume of semen. Their thick, yellowish secretion is rich in fructose, Vitamin C, prostaglandins, and other substances which nourish and activate the sperm passing through the tract. The duct of each seminal vesicle joins that of the vas deferens on the same side to form the ejaculatory duct. Sperm and seminal fluid enter the urethra together during ejaculation.

This is a single gland about the size and shape of a chestnut. It encircles the upper part of the urethra just below the bladder. Prostate gland secretion is a milky fluid that plays a role in activating sperm. During ejaculation it enters the urethra through several small ducts. Since the prostate is located immediately anterior to the rectum, its size and texture can be palpated by digital examination through the anterior rectal wall.

These are tiny pea shaped glands inferior to the prostate gland. They produce a thick, clear mucus that drains into the penile urethra. This secretion is the first to pass down the urethra when a man becomes sexually excited. It is believed to cleanse the urethra of traces of acidic urine, and it serves as a lubricant during sexual intercourse.

Semen is a milky white somewhat sticky mixture of sperm and accessory gland secretions. The liquid provides a transport medium and nutrients and contains chemicals that protect the sperm and aid their movement. Mature sperm cells are streamlined and contain little cytoplasm or stored nutrients. The fructose in the seminal vesicle secretion provides essentially all of their energy fuel. The relative alkalinity of semen as a whole (pH 7.2-7.6) helps neutralize the acid environment (pH 3.5-4) of the female's vagina, protecting the delicate sperm. Sperm are very sluggish under acidic conditions (below pH 6). Semen also contains seminal plasmin, a chemical that inhibits bacterial multiplication, the hormone relaxin, and certain enzymes that enhance sperm motility.

Semen also dilutes sperm, without such dilution, sperm motility is severely impaired. The amount of semen propelled out of the male duct system during ejaculation is relatively small, only 2-5ml (teaspoonish), but there are between 50 and 130 million sperm in each milliliter.

Male infertility may be caused by obstructions of the duct system, hormonal imbalances, environmental estrogens, pesticides, excessive alcohol, and many other factors. One of the first series of tests done when a couple has been unable to conceive is semen analysis. Factors analyzed include sperm count, motility, morphology (shape and maturity), semen volume, pH, and fructose content. A sperm count lower than 20 million per milliliter makes impregnation improbable.

This includes the scrotum and the penis.

The scrotum is a divided sac of skin that hangs outside the abdominal cavity, between the legs and at the root of the penis. Under normal conditions, the scrotum hangs loosely from its attachments, providing the testes with a temperature that is below body temperature. This is a rather exposed location for a man's testes, which contain his entire genetic heritage, but apparently viable sperm cannot be produced at normal body temperature. The scrotum, which provides a temperature about 3 degrees centigrade lower, is necessary for the production of healthy sperm. When the external temperature is very cold, the scrotum becomes heavily wrinkled as it pulls the testes closer to the warmth of the body wall. Thus, changes in scrotal surface area can maintain a temperature that favors viable sperm production.

The penis is designed to deliver sperm into the female reproductive tract. The skin covered penis consists of a shaft which extends in an enlarged tip (the glans penis). The skin covering the penis is loose, and it folds downward to form a cuff of skin called the 'prepuce' or foreskin around the proximal end of the glans. Frequently the foreskin is surgically removed shortly after birth, by a procedure called circumcision.

Internally, the spongy urethra is surrounded by three elongated areas of erectile tissue, a spongy tissue that fills with blood during sexual excitement. This causes the penis to enlarge and become rigid. This event is called an erection, which helps the penis serve as a penetrating organ to deliver the semen into the female's reproductive tract.

The main role of the male reproductive system is to produce sperm and testosterone.

The interstitial cells produce testosterone, the most important hormonal product of the testes. During puberty, as the seminiferous tubules are being prodded to produce sperm by FSH, the interstitial cells are being activated by luteinizing hormone (LH), sometimes called interstitial cell stimulating hormone (ICSH), which is also released by the anterior pituitary gland. From this time on, testosterone is produced continuously (more or less) for the rest of the man's life. The rising blood level of testosterone in the young male stimulates his reproductive organs to develop to their adult size, underlies the sex drive, and causes the secondary male sex characteristics to appear. These include: deepening of the voice due to enlargement of the larynx, increased hair growth all over the body particularly in the axillary and pubic regions and the face, enlargement of skeletal muscles to produce the heavier muscle mass typical of the male physique, and increased heaviness of the skeleton due to thickening of the bones.
Because testosterone is responsible for the appearance of these typical masculine characteristics, it is often referred to as the 'masculinizing' hormone.

If testosterone is not produced, the secondary sex characteristics never appear in the young man, and his other reproductive organs remain childlike. This is sexual infantilism. Castration of the adult male (or the inability of the interstitial cells to produce testosterone) results in a decrease in the size and function of the reproductive organs as well as a decrease in the libido. Sterility also occurs because testosterone is necessary for the final stages of sperm production.

Week 1
- period begins
Week 2
- uterus has shed its lining through your period
- a new bed of blood-rich tissue is delevoping
- eggs are ripening in one of the ovaries
- preparing to release an egg
Week 3
- ripened egg is released and is travelling down a fallopian tube
- conception occurs
- implantation of blastocyst, may have some spotting or bleeding
Week 4
- may be expecting period
- early signs of pregnancy, such as, fatigue, breast soreness, and mood swings
Week 5
- period is late
- hormone changes will cause swelling of breasts, increase in hunger, and nausea
- uterus grows and puts pressure on bladder cause an increase in urination
Week 6
- nausea, morning sickness, food cravings
Week 7
- loss or gain of weight
Week 8
- uterus grows to the size of an orange
- increase in oil secretions and change in hormone may result in skin breakouts
- there is about 4 times the normal levels of progesterone and estrogen hormones
Week 9
- breasts may be fuller and very sensitive
- waistline may be growing
- heartburn and indigestion as body adjusts to pregnancy hormones
Week 10
- morning sickness may start to ease
- veins in abdomen, breasts, and legs will be more noticeable due to increase in blood volume
Week 11
- uterus grows to the size of a grapefruit
Week 12
- uterus will shift up and forward as it grows and won't be pressing on bladder
- morning sickness is usually better
- less tired
- headaches and light-headedness may occur due the increased blood
Week 13
- the ligaments that hold up your uterus stretch to accommodate your growing uterus causing some achiness
Week 14
- hormones have relaxed bowel muscles causing them to work slower and less efficiently that may result in constipation
- uterus is also pressing on your bowel
- the veins on your chest and breasts are dilated and more noticeable
- the areolas may be darkening and growing in diameter
Week 15
- the uterus is three to four inches below the navel. Fundal height is the distance from the top of the uterus (fundus) to the pubic bone.
Week 16 - 17
- the uterus is about 1 1/2 to 2 inches below the navel
- weight gain is between five and ten pounds
Week 18
- the uterus is just below the navel
Week 19
- several skin changes may occur due to hormones such as the "mask of pregnancy" - blotchy patches on your forehead, cheeks, nose and chin, Itchy skin, and/or dry and flaky in certain areas and many pregnant women develop rashes, particularly on the stretched skin
Week 20
- the uterus is at the navel
- some tenderness as your belly button becomes an "outtie" from the uterus pressing on it
- the line between your navel (linea nigra) and pubic hair has darkened; it will fade after delivery
Week 21
- the uterus is about 1/2 inch above thenavel
- the average weight gain is between 10 and 15 pounds at this point
- ankles and feet may be swelling
Week 22
- the uterus is nearly an inch above the navel
- gaining weight more steadily now as your baby continues to fill out
Week 23
- feeling kicks and jabs
- the uterus is about 1 1/2 inches above the navel
Week 24
- the uterus is 1 1/2 to 2 inches above the navel
Week 25
- the uterus is the size of a soccer ball
- the uterus places pressure on your back and pelvis and may cause periodic shooting pains in thelower back and legs
Week 26
- the uterus is about 2 1/2 inches above the navel
- "Braxton Hicks" Contractions may start to happen, this is a sudden tightening and then relaxing of the uterus. These are normal, usually painless or feel similar to menstrual cramps and happen at irregular intervals.
Week 27
- the uterus is close to the rib cage now, and thelungs may not be able to fully expand causing a shortness of breath
Week 28
- the uterus is around 3 inches above the navel
- average weight gain is between 17 and 24 pounds at this point
Week 29 - 30
- difficulty sleeping
- the aorta and vena cava are slightly to the right of the center of your back, so laying/sleeping on the left side as much as possible ensures an unobstructed blood flow to the organs and extremities
Week 31
- the uterus is about 4 1/2 inches above the navel
Week 32
- the uterus is measuring about 5 inches above the navel
- the uterus is pushing the organs causing heartburn, constipation, indigestion and breathlessness
Week 33
- gaining about a pound a week
- mild edema is normal
- delveopment of pre -eclampsia. Signs are: severe headache; seeing "spots" or "flashing lights" while at rest; sudden increase in swelling, such as over 2-3 days, especially of the face; abdominal pain; and nausea, vomiting, and feeling sick, contact your caregiver immediately.
Week 34- 35
- the cervix may be stretching, thinning (effacement) and opening (dilation)
Week 36
- the average weight gain now is between 25 and 30 pounds
Week 37
- vaginal discharge may be heavier and will have more cervical mucous in it as the body prepares for labor
Week 38
- contractions may be felt
- false labor contractions are irregular and can be very painful. These contractions may be felt in various parts of the body (back, lower abdomen, pelvis)
- true labor contractions start at the top of the uterus and then spread over the entire uterus, through the lower back and into the pelvis. True labor will become stronger and more painful and won't be alleviated by changing position.
Week 39
- the baby settles into the pelvis
- center of gravity shifts which may make you feel off-balance
- easier to breathe
- the uterus is pushing on the bladder causing an increase in urination
- the uterus is 6 1/2 to 8 inches above the navel
Week 40
- labour (labor) may occur anytime

TOP

Ovualtion to 12 - 24 hours - single sperm penetrates the egg and a joining of gentic information occurs. A single cell is formed, call a zygote
Day 2-3 - the zygote travels down the fallopian tube, cells divide into a mulberry-like mass which is 1/100 inch wide, this is called a morula
Day 5 - with additional cell division, the morula becomes a blastocyte, with an inner core and an outer shell of cells. The outer group of cells become the membranes that nourish and protect the inner group of cells, which becomes the fetus.
Day 7 - 9 -the blastocyte implants in the uterus. At this point the endometrium (the lining of the uterus) has grown and is ready to support a fetus. The blastocyte burrows into the endometrium where it receives nourishment. It is barely visible, but doubles every 24 hours. The placenta and supporting infrastructure for pregnancy develop at this time as well. It is estimated that up to 5 5% of zygotes never reach this phase of growth

Week 2 - cells of the embryo are multiplying, and taking on specific functions. This process is called tissue differentiation.
Week 3 - formation of the heart, the beginning development of the brain and spinal cord, and the beginning of the gastrointestinal tract.
Weeks 4 and 5 - 1/4 inch long: the beginnings of the vertebra, the lower jaw, the larynx (voice box), and the rudiments of the ear and eye. The heart, which is still outside body, now beats at a regular rhythm. Although arm and leg "buds" are visible with hand and foot "pads," the embryo still has a tail and cannot be distinguished from pig, rabbit, elephant, or chick embryo.
Week 6 --1/2 inch, 1/1000 of an ounce: the formation of the nose, jaw, palate, lung buds. The fingers and toes form, but may still be webbed. The tail is receding, and the heart is almost fully developed.
Week 7 - 7/8 inch, 1/30 ounce (less than an aspirin): the eyes move forward on the face, and the eyelids and tongue begin to form. All essential organs have begun to form.
Week 8 -1 inch, 1/15 ounce: The embryo now resembles a human being. The facial features continue to develop and the external genitalia and the external ear appears. The circulation through the umbilical cord is well developed. The long bones begin to form and the muscles are able to contract.

At this point the embryo is developed enough to call a fetus. All organs and structures found in a full-term newborn are present.
Weeks 9 to 12 -- 3 inches, 1 ounce: the head comprises nearly half of the fetus' size and the face is well formed. The eyelids close now and will not reopen until about the 28th week. The tooth buds for the baby teeth appear. The genitalia are now clearly male or female.

Weeks 13 to 16 -- 6 inches: the skin of the fetus is almost transparent, fine hair develops on the head. The fetus makes active movements, including sucking, which leads to some swallowing of the amniotic fluid. A thin dark substance called meconium is made in the intestinal tract. The heart beats120-150 beats per minute and brain waves detectable.
Weeks 17 to 20 -- 8 inches: eyebrows and lashes appear and nails appear on fingers and toes. The can mother feel the fetus moving and the fetal heartbeat can be heard with a stethoscope.
Weeks 21 to 24 -- 11.2 inches, 1 lb. 10 oz.: all the eye components are developed, footprints and fingerprints are forming, and the entire body covered in cream-cheese-like vernix caseosa. The fetus now has a startle reflex.

Weeks 25 to 28 -- 15 inches, 2 lbs. 11 oz.: rapid brain development. The nervous system is developed enough to control some body functions, and the eyelids open and close. A baby born at this time may survive, but the chances of complications and death are high.
Weeks 29 to 32 -- 15 -17 inches, 4 lbs. 6 oz.: there is a rapid increase in the amount of body fat and the fetus begins storing its own iron, calcium, and phosphorus. The bones are fully developed, but still soft and pliable. There are rhythmic breathing movements present, the fetal body temperature is partially self-controlled, and there is increased central nervous system control over body functions.
Weeks 33 to 36 -- 16 -19 inches, 5 lbs. 12 oz. to 6 lbs. 12 oz.: The body hair begins to disappear. A baby born at 36 weeks has a high chance of survival.
Weeks 37 to 40 -- 19 - 21 inches 7 or 8 pounds: At 38 weeks, the fetus is considered full term. It fills the entire uterus, and its head is the same size around as its shoulders. The mother supplies the fetus with the antibodies it needs to protect it against disease.