Female Anatomy

Anatomy

feature a body with nipple at apex
- nipple surrounded by areola
  - feature sensory nerve fibers that trigger the milk ejection (let-down) reflex
  - capillaries and nerves close to skin surface here
- areolar gland secretions protect nipple from chapping/cracking during nursing
axillary tail (tail of spence) extends towards armpit
suspensory ligaments hold in place
non-lactating feature adipose and collagen
mammary glands develop in pregnancy
- 15-20 lobes with alveoli (acini) lead to lactiferous duct → open into lactiferous sinuses → into nipple
- glands atrophy after nursing ceases
myoepithelial cells are contractile cells found around ducts/acini that function in milk expression (stimulated y oxytocin)
breast milk is comprised of fats, carbs, proteins, vitamins, minerals, and water
also contain bioactive factors that augment the immature immune and digestive systems

Initial stage (3-5 days postpartum) produces a nutrient-rich colostrum
milk “matures” after initial stage and shifts to a supply-demand system
- breats emptying is crucial to maintaining production
  - prolactin stimulates milk production
let-down reflex invloves oxytocin
- nipple nerve endings signal the hyothalamus to release oxytocin
  - milk forced from alveoli into ducts

external genitalia = vulva
- mons pubis → fat over pubic symphysis
- labia majora and minora surround pudendal cleft
  - laia minora form the prepuce (clitoral hood)
- pudendal cleft contains clitoris and vestibule
- clitoris → erectile tissues that swell if aroused
  - more nerve endings than any other body part
- vulvar vestibule → surrounds vaginal and urethral openings and contains the vestibular glands
  - lesser vestibular (skene’s/paraurethral) glands
    - secrete antimicrobial and ejaculate proteins
      - similar to prostate secretions
  - greater vestibular (bartholin’s) glands
    - secrete vaginal lubricants
highly variable morphology
- variations based on amount of estrogen influence during development
  - more estrogen = larger, thicker structures
  - decrease in estrogen cn cause atrophy
most variation occurs within the size, shape, and color of the labia minora
- 2018 study measured the labia of 657 participants (age range 15-84) and found:
  - average labia majora= 3.1 inches long
  - average labia minora = 1.65 inches long
  - BMI correlated with labia majora size
  - vaginal delivery correlated with labia majora length

internal pudendal a. supplies the dorsal aa.
- dorsal aa. gives rise to the deep dorsal aa., which supplies the corpora cavernosa that fill eith blood during erections
- tunica albuginea
  - surrounds and separates the corpora cavernosa
  - forms the body and crura
  - helps sustain erection
dorsal vv. drain to the vesical plexus → internal iliac vv. → common iliac vv. → IVC

located between bladder and rectum
8-10 cm distensible muscular canal
- able to expand and priduces its own lubricant
- vaginal membrane (“hymen”) around the vaginal opening
  - typically presents as a semi-circula ring of tissue that may be a fetal remnant
    - rarely cover entire opening (imperforate hymen)
  - many myths surround this structure
adventitia, muscularis, and mucosa layers
- aglandular, but lubricated by serous fluid from cervical glands and Bartholin’s glands’ secretions
involved on sexual pleasure, menstruation, pregnancy, and childbirth
- walls contain many sensory nerve endings
- allows for passage of mentrual fluid
- allows for entry of sperm into the uterus
- referred to as the “birth canal” during childbirth
acidic environment (pH 3.8-5.0) impacted by age (4.0-4.5 in reporductive years), hydration status, diet, and safe interncourse
- pH too low = reduces fertility
- pH too high = increased risk of infection
- microorganisms stabilize vaginal ecosystem
  - lactobacillus acidophilus ferments glycogen from decay of vaginal mucosa into lactic acid and releases H+

thick, muscular chamber that opens into the roof of the vagina and tilts forwards over the urinary bladder
harbors and expels a fetus
three main parts:
- fundus
- body (corpus)
- cervix → connects to vagina
  - glands secrete cervical mucus (20-60mg/day or up to 600 mg during ovulation)
  - protects from bacteria and can prevent sperm from entering uterus
uterine wall made of three layers
- perimetrium → external serosa layer
- myometrium → middle muscular layer
  - thickest layer made mostly of smooth muscle
  - produces labor contractions
- endometrium → inner mucosa layer
  - simple columnar epithelium
  - multiple glands and cell types
  - functional layer superficially (menstrual shed)
  - basal layer (deep) that regenerates a new functional layer each cycle
  - site of attachement during pregnancy