Gynecological Anatomy & Physiology

Gynecological Anatomy & Physiology

REPRODUCTIVE AND SEXUAL HEALTH

PUBERTAL DEVELOPMENT:

Puberty is the stage of life at which the secondary sex changes

Girls - age 10 to13 years

Theory: must reach a critical weight of approx. 95lbs (43kgs)

Boys - age 12 to 14 years

The role of Androgen- hormones responsible for :

Muscular development

Physical growth

Increase sebaceous gland secretion (acne)

“ Testosterone -1° androgenic hormone”

In girls, testosterone influences the development of

labia majora, clitoris, and axillary & pubic hair latter termed as (adrenarche)

REPRODUCTIVE AND SEXUAL HEALTH

Secondary sex characteristic of boys occurs in order:

increase in weight

growth of testes

growth of face, axillary, and pubic hair

voice changes

penile growth

increase in height

spermatogenesis

Secondary sex characteristic of girls occurs in order:

1. growth spurt

2. increase in the traverse diameter of the pelvis

3. breast development (thelarche)

4. growth of pubic hair (adrenarche)

5. onset of menstruation (menarche 12.5 y/o ave.)

6. Ovulation occurs 1 – 2 years after menarche

7. growth of axillary hair (adrenarche)

8. vaginal secretion

FEMALE REPRODUCTIVE SYSTEM: GYNECOLOGY

External Structures

Mons pubis/ Mons veneris – pad of adipose tissues, which lives over the symphysis pubis, which protects the surrounding delicate tissue from trauma.

Labia majora – longitudal folds of pigmented skin extending from the mons pubis to the perineum. Contains the Bartholin’s gland that secretes yellowish mucus that acts as a lubricant during sexual activity.

Labia minora – soft longitudal skin folds between the Labia majora.

Glans clitoris – erectile tissue located at the upper end of Labia minora; primary site of sexual arousal.

FEMALE REPRODUCTIVE SYSTEM:

External Structures continue

5. Vestibule – a narrow space seen when labia minora are separated that also contains the vaginal introitus, Bartholin’s gland and urethral meatus.

6. Urethral Meatus – small opening bet, the clitoris and vaginal orifice for the purpose of urination.

7. Vaginal orifice/introitus/opening – external opening of the vagina that contains the hymen.

8. Hymen – a membranous tissue ringing the vaginal introitus

9. Perineum – tissue between the anus and vagina. Site of episiotomy

The external genitalia’s blood supply:

Arteries: a. pudental artery b. inferior rectus artery.

Vein: Pudendal vein

B. Internal Structures

Ovaries – female sex glands located on each side of the uterus with two ovaries (4 x 2 x 1.5 cm thick).

Ovaries are formed with 3 principal divisions:

a. A protective layer of surface epithelium

b. The cortex filled with the ovarian and graafian follicle

c. The central medulla containing nerves, blood vessels, lymphatic tissue and some smooth muscle tissue

Fxn: - Ovulation (release of ovum) and Secretion of hormones like estrogen and progesterone .

Estrogen - help to prevents osteoporosis, and atherosclerosis

and potential risk for breast cancer endometrial cancer

B. Internal Structures continue

2. Fallopian Tubes – 4 inches (10 cm) long from each sides of the fundus;

Divided on four separate part:

1. Intramural portion- most proximal (1cm in length)

2. Isthmus portion- extremely narrow (2cm)

Important: tubal ligation

3. Ampulla- longest portion (5cm) and widest part

Function: site of fertilization

4. Infundibular portion- funnel shape with Fimbrae (2cm) finger like projections.

Function: responsible for the transport of mature ovum from ovary to uterus.

3. Uterus – hollow pear-shaped muscular organ.

Size: 3 inches long (5-7cm), 2 inches wide(5cm) and 1 inch thick (3x2x1)

Wt: 60 gms. in non pregnant Location: lower pelvis

Parts: Corpus, Isthmus, and Cervix

Position: anteverted and anteflexed

Layers: perimetrium, myometrium and endometrium

Function:

1. to receive the ova to fallopian tube place for implantation and nourishment during fetal growth furnish protection to a growing fetus

2. aids in labor and delivery

Cervix (2-5cm long)

Internal cervical os -an impt. relationship in estimating the External cervical os level of dilatation of the fetus in the birth canal before birth.

Uterus continue

Nerve Supply:

Efferent (motor) nerve- spinal ganglia (T5 to T10)

Afferent (sensory) nerve - hypogastric plexus (T-11 & T-12)

Impt: Controlling pain in labor ( Epidural anesthesia)

Uterine Ligaments:

1. Broad Ligaments – fr. the sides of uterus to pelvic walls

2. Round Ligaments – fr. sides of uterus to mons pubis.

3. Cardinal and uterosacral ligaments- provides middle support

4. Pelvic muscular floor ligaments- provide lower support

3. Vaginal Canal – 3-4 inch long dilatable canal between the bladder and the rectum; contains rugae that permits stretching without tearing.

Anterior Vaginal wall- 6-7 cm (anterior fornices)

Posterior Vaginal wall- 8-9 cm (posterior fornices)

Function: 1. passageway for menstrual discharges

2. receives penis during intercourse and

3. serves as birth canal.

- lined with stratified squamous epithelium

- Bulbocavernosus : a circular muscle acts as voluntary sphincter (Kegel exercises)

Blood supply to the vagina:

Arteries: vaginal artery branch of internal iliac artery

Vein: pudental vein

Vagina continue …

The external genitalia’s blood supply : mainly from the

a. pudental artery and

b. a portion of inferior rectus artery.

Nerve supply: has both parasympathetic & sympathetic

(S-1 to S-3 levels)

Nerve supply of the anterior portion: (L1)

a. Ilio-inguinal nerves b. Genito-femoral nerves

Nerve supply of the posterior portion: (S3)

Pudendal nerves

“ This is the reason why one type of anesthesia used for childbirth is called Pudendal block.”

MALE REPRODUCTIVE SYSTEM: ANDROLOGY

A. External Structures

1. Penis : the male organ of copulation; a cylindrical shaft consisting of:

a. corpora cavernosa - t wo lateral columns of erectile tissue

b. corpus spongiosum - encases the urethra

-The glans penis , a cone-shaped expansion of the corpus spongiosum that is highly in express males.

- Erection is stimulated by parasympathetic nerve

Scrotum : a pouch hanging below the penis that contains the testes .

3. Testes: two solid ovoid organs 4-5 cm long and 2-3 wide , divided into lobes containing

Seminiferous tubules - produce spermatozoa.

Leydig cells - testosterone production .

MALE REPRODUCTIVE SYSTEM:

MALE REPRODUCTIVE SYSTEM: A. External Structures continue SPERMATOZOA are produced by: Hypothalamus Control by GnRH (+/-) feedback Anterior Pituitary gland FSH / LH Testes FSH - release of Androgen Binding Protein (ABP) which promote SPERMATOGENESIS LH - release of Testosterone. “ Spermatozoa does not survive at body temperature. They usually survive 1°F lower than body temperature”.

B. Internal Structures

1. Epididymis: serves as reservoir for sperm storage and maturation. Approximately 20 ft. it takes 12-20 days for the sperm to travel the length of Epididymis.

A total of 64 days before they reach maturity.

(“Treatment= 2 months” ).

Aspermia - (absence of sperm)

Oligospermia- if < 20 million sperm/ ml

2. Vas deferens: a duct extending from epididymis to the ejaculatory duct and seminal vesicle, providing a passageway for sperm. (sperm mature).

Varicocele- varicosity of internal spermatic cord

Vasectomy (male birth control)

3. Seminal vesical: are two convoluted pouches that lie along the lower portion of the bladder and empty into the urethra by the way of ejaculatory ducts

MALE REPRODUCTIVE SYSTEM: B. Internal Structures continue 4. Ejaculatory duct: the canal formed by the union of the vas deferens and the excretory duct of the seminal vesicle, which enters the urethra at the prostate gland. 5. Prostate Gland: located just below the urinal bladder. Secretes alkaline and most of the seminal fluid. 6. Bulbourethral glands or Cowper’s Gland: adds alkaline fluid to the semen. 7. Urethra: the passageway for both urine and semen, extending from the bladder to the urethral meatus . (8 inches in long)