Module 2 _PART 3

Vulva

The collective term for the external female genitalia, derived from the Latin word meaning "covering."

Mons Veneris

A pad of adipose tissue over the symphysis pubis covered by coarse, curly hair that protects the pubic bone junction from trauma.

Labia Majora

Two adipose and connective tissue folds lateral to the labia minora, covered by pubic hair, that protect the external genitalia, distal urethra, and vagina.

Labia Majora Trauma Vulnerability

The looseness of the connective tissue base makes the labia majora susceptible to extensive edema formation following childbirth or trauma.

Labia Minora

Two hairless folds of connective tissue posterior to the mons veneris, small before menarche, full in childbearing years, and atrophied post-menopause.

Labia Minora Histology

Pink folds covered externally by skin and internally by mucous membrane, richly supplied with sebaceous glands that may develop localized sebaceous cysts.

Monthly Vulvar Examination

A monthly self-examination performed by women to detect infection, cysts, or structural abnormalities of the vulva.

Vestibule

The flattened, smooth surface inside the labia minora containing the openings of the urethra and vagina.

Clitoris

A small (1 to 2 cm) rounded organ of erectile tissue at the forward junction of the labia minora, covered by the prepuce, serving as the center of sexual arousal and orgasm.

Clitoral Erection Mechanism

Rich arterial blood flow engorges the clitoris while contraction of the surrounding ischiocavernosus muscle blocks venous outflow.

Skene's Glands (Paraurethral Glands)

Paired glands located lateral to the urinary meatus whose ducts open into the urethra to secrete lubricating alkaline fluid.

Bartholin's Glands (Vulvovaginal Glands)

Paired glands located lateral to the vaginal opening whose ducts open into the distal vagina to secrete lubricating alkaline fluid.

Function of Skene's and Bartholin's Secretions

Secretes lubricating fluid during coitus with an alkaline pH that enhances sperm survival in the vagina.

Fourchette

The posterior ridge of tissue formed by the fusion of the labia minora and labia majora, sometimes incised during an episiotomy.

Episiotomy

A surgical incision of the fourchette and perineal area during childbirth to enlarge the vaginal opening.

Perineal Muscle (Perineal Body)

Muscular area posterior to the fourchette that stretches during birth to permit fetal head passage; flexibility is improved by Kegel's, squatting, and tailor-sitting.

Hymen

A tough, elastic semicircle of tissue covering the childhood vaginal opening that may be torn by coitus, tampon use, or vigorous physical activity.

Imperforate Hymen

A completely closed hymen that obstructs menstrual flow and intercourse, requiring surgical incision.

Vulvar Blood Supply

Arterial supply mainly from the pudendal artery and inferior rectus artery; venous drainage via the pudendal vein.

Vulvar Vascular Complications

Fetal head pressure on the pudendal vein can cause labial varicosities; rich vascularity promotes large hematomas with trauma but facilitates rapid healing.

Vulvar Nerve Supply

Anterior vulva innervated by ilioinguinal and genitofemoral nerves (L1); posterior vulva and vagina innervated by the pudendal nerve (S3).

Pudendal Nerve Block

A local anesthetic block administered at the S3 pudendal nerve level to eliminate pain sensation at the perineum during childbirth.

Female Internal Reproductive Structures

The internal pelvic reproductive organs consisting of the ovaries, fallopian tubes, uterus, and vagina.

Ovaries

Almond-shaped female gonads measuring 4 cm long, 2 cm wide, and 1.5 cm thick, with a grayish-white, pitted surface containing follicles and the corpus luteum.

Graafian Follicle

An unruptured, glistening, fluid-filled ovarian structure containing an ovum ready for discharge.

Corpus Luteum

The yellow glandular structure formed on the ovarian surface following ovulation.

Functions of the Ovaries

Producing, maturing, and discharging ova, secreting estrogen and progesterone, and regulating the menstrual cycle.

Effects of Pre-Pubertal Oophorectomy

Absence of ovarian estrogen prevents pubertal breast development and leads to a more masculine pubic hair distribution pattern.

Post-Menopausal Ovarian Changes

Cessation of ovarian estrogen production causes atrophy of the uterus, breasts, and ovaries, along with increased osteoporosis and fracture risk.

Estrogen and Cardiovascular Health

Estrogen incorporates cholesterol and helps lower circulating blood cholesterol, limiting atherosclerosis until post-menopausal estrogen withdrawal occurs.

Estrogen Supplementation Risk

Long-term post-menopausal hormone therapy carries elevated risks for breast cancer and cerebrovascular accidents (stroke).

Divisions of the Ovary

1. Protective surface epithelium; 2. Ovarian cortex (housing primordial oocytes, maturing ova, and steroid synthesis); 3. Central medulla (containing nerves, blood vessels, lymphatics, and smooth muscle).

Fallopian Tubes (Oviducts)

Paired 10-cm muscular tubes extending from the uterine cornua to the ovaries that transport ova and serve as the site of fertilization.

Divisions of the Fallopian Tube

Interstitial portion (1 cm within uterine wall), isthmus (2 cm narrow segment), ampulla (5 cm longest site of fertilization), and infundibulum (2 cm funnel rimmed with fimbriae).

Interstitial Portion of Fallopian Tube

The most proximal 1-cm segment within the uterine wall with a 1-mm lumen.

Isthmus of Fallopian Tube

The narrow 2-cm segment distal to the interstitial portion, targeted for cut and occlusion during tubal ligation sterilization.

Ampulla of Fallopian Tube

The longest (5 cm) segment of the fallopian tube where fertilization of the ovum typically occurs.

Infundibulum and Fimbriae

The distal 2-cm funnel-shaped tube ending rimmed with hair-like fimbriae that guide the ovulated egg into the lumen.

Fallopian Tube Propulsion Mechanism

Peristaltic contractions of the muscular wall, ciliary beating of the mucous lining, and lubricating, nutrient-rich mucus guide the ovum.

Uterus

A hollow, pear-shaped, muscular pelvic organ located posterior to the bladder and anterior to the rectum that houses and nourishes the developing fetus.

Uterine Growth and Adolescent Pregnancy

Uterine growth begins at age 8 and reaches adult size (~60 g, 5–7 cm long) near age 17; immature uterine size in younger girls contributes to low birth weight infants.

Post-Pregnancy Uterine Dimensions

Following pregnancy, the uterus permanently remains enlarged at approximately 9 cm long, 6 cm wide, 3 cm thick, and 80 g in weight.

Divisions of the Uterus

Body (corpus), isthmus, and cervix.

Corpus (Body of Uterus)

The uppermost, largest portion of the uterus that expands during pregnancy; includes the upper attachment points (cornua) and the superior dome (fundus).

Uterine Fundus

The uppermost rounded portion of the uterine body between fallopian tube insertions, palpated to assess fetal growth, contraction force, and postpartum involution.

Isthmus of Uterus

The short (1 to 2 mm nonpregnant) transitional segment between body and cervix that expands during pregnancy and is incised during cesarean births.

Cervix

The lowest cylindrical uterine segment (2 to 5 cm long, one third of total organ), half projecting into the vagina, featuring a central canal between internal and external os.

Internal and External Cervical Os

The internal os opens into the isthmus; the external os opens into the vagina at the level of the ischial spines.

Vagina

A hollow musculomembranous canal 6 to 7 cm anteriorly and 8 to 9 cm posteriorly, slanting inward and downward between the bladder and rectum.

Vaginal Fornices

Recesses encircling the cervix: the posterior fornix pools semen for sperm transit, while anterior and lateral fornices allow pelvic palpation of the bladder and ovaries.

Vaginal Rugae

Transverse epithelial folds along the vaginal walls providing elasticity and expansion for full-term fetal passage without tearing.

Bulbocavernosus Muscle

A circular voluntary sphincter muscle at the vaginal orifice toned by Kegel exercises to support birth and postpartum pelvic integrity.

Vaginal Blood and Nerve Supply

Supplied by the vaginal artery (from internal iliac) and innervated by S1–S3 roots; rich vascularity causes profuse bleeding with trauma but allows rapid healing.

Döderlein's Bacillus and Vaginal pH

Normal lactobacilli ferment glycogen from vaginal epithelium into lactic acid to maintain an acidic protective pH; alkaline shift to pH 7.5 post-menopause increases vulvovaginitis risk.

Bony Pelvis

A skeletal basin composed of the right and left innominate bones, sacrum, and coccyx forming the birth canal.

Symphysis Pubis

The anterior fibrocartilaginous joint uniting the pubic bones of the pelvic girdle.

True Conjugate (Conjugata Vera)

Anteroposterior pelvic inlet diameter from the upper margin of the symphysis pubis to the sacral promontory; minimum normal is 11 cm (measured via X-ray/ultrasound).

Diagonal Conjugate

Distance from the lower border of the symphysis pubis to the sacral promontory; normal is 12.5 to 13 cm (measured via manual vaginal exam).

Obstetric Conjugate

The narrowest inlet diameter from the inner surface of the symphysis pubis to the sacral promontory; calculated by subtracting 1.5 to 2 cm from the diagonal conjugate.

Intertuberous Conjugate (Bi-ischial Diameter)

The transverse diameter of the pelvic outlet measured between the inner borders of the ischial tuberosities; must be at least 8 cm.

Types of Pelvic Shapes

Gynecoid (classic female, wide/rounded), Android (male type, narrow heart-shaped), Anthropoid (apelike, narrow oval), and Platypelloid (wide transverse, flat anteroposterior).

Gynecoid Pelvis

The classic well-rounded female pelvis ideal for vaginal birth.

Android Pelvis

A narrow, heart-shaped male pelvic configuration unfavorable for vaginal delivery.

Anthropoid Pelvis

A narrow, oval-shaped pelvis with an elongated anteroposterior diameter resembling an ape pelvis.

Platypelloid Pelvis

A flattened pelvic shape with a wide transverse and short anteroposterior diameter.

False Pelvis

The shallow superior half of the pelvis above the linea terminalis that supports the enlarging uterus but is not obstetrically significant.

Linea Terminalis

The imaginary anatomical ridge dividing the superior false pelvis from the inferior true pelvis.

True Pelvis

The inferior obstetric pelvis bounded by pubes, ilia, ischia, sacrum, and coccyx, comprising the inlet, cavity, and outlet.

Pelvic Inlet Diameters

Transverse diameter (13.5 cm), right and left oblique diameters (12.75 cm), and anteroposterior diameter (11 cm).

Pelvic Cavity

The curved space bounded by pelvic walls between the inlet and the outlet.

Pelvic Outlet

The inferior pelvic boundary bordered by the coccyx, ischial tuberosities, and inferior pubic arch, featuring an anteroposterior diameter wider than its transverse diameter.

Mammary Glands (Breasts)

Accessory ectodermal reproductive organs located anterior to pectoral muscles, expanding at puberty via estrogen-driven fat and connective tissue deposition.

Gynecomastia

Temporary, benign enlargement of male breast tissue during puberty, commonly observed in adolescent and obese boys.

Clinical Breast Examination

Professional yearly manual palpation covering all breast quadrants and axillary extensions to detect breast lesions.

Lobes of the Breast

Approximately 20 glandular tissue divisions per breast containing milk-secreting acinar cells connected to lactiferous ducts.

Acinar Cells

Specialized epithelial cells within breast lobes that synthesize and secrete milk.

Lactiferous Ducts and Ampullae

Ducts that convey milk from lobes to 20 nipple openings; widen into subareolar ampullae that act as milk reservoirs.

Nipple Erection and Oxytocin Reflex

Tactile stimulation of smooth muscle in the nipple triggers posterior pituitary oxytocin release, contracting myoepithelial cells to eject milk.

Areola

The darkly pigmented skin circular zone (~4 cm) surrounding the nipple containing elevated sebaceous Montgomery's tubercles.

Montgomery's Tubercles

Sebaceous glands situated within the areolar skin that secrete protective lubricants during lactation.

Mammary Blood Supply

Extensive vascular network supplied by thoracic branches of the axillary, internal mammary, and intercostal arteries delivering nutrients for milk synthesis.