Phys: Female Repro

Ovaries

Female internal reproductive organs located in the pelvic cavity that secrete female sex hormones (estrogen and progesterone) and develop and release female gametes (ova).

Ovarian Cortex

The outer layer of the ovary containing ovarian follicles, theca cells, and granulosa cells.

Ovarian Medulla

The inner vascularized region of the ovary surrounded by the cortex.

Endometrium

The mucosal inner lining of the uterus that undergoes cyclical proliferation, vascularization, and sloughing during the menstrual cycle.

Myometrium

The thick, smooth muscle layer of the uterine wall responsible for uterine contractions during menses and labor.

Cervix

The lower anatomical portion of the uterus that connects the uterine cavity to the vagina.

Vagina

An elastic fibromuscular canal with rugae containing Lactobacillus acidophilus, a resident bacterium that maintains an acidic pH to discourage bacterial proliferation and prevent infection.

Cooper Ligaments

Suspensory fibrous structures in the breast that separate and support 15 to 20 pyramid-shaped lobes.

Acini

Secretory units within breast lobules lined by epithelial cells that synthesize milk during lactation, surrounded by myoepithelial cells that contract in response to oxytocin.

Clitoris

Sensory-rich female external erectile structures that become engorged with blood alongside the labia minora and urethral tissues during pelvic vascular activation in the sexual response cycle.

Gonadotropin-Releasing Hormone (GnRH)

Hypothalamic hormone that acts on the anterior pituitary to stimulate the synthesis and secretion of LH and FSH.

Follicle-Stimulating Hormone (FSH)

Anterior pituitary gonadotropin that drives the growth of 6 to 12 primary follicles, granulosa cell proliferation, and estrogen secretion during the early follicular phase.

Luteinizing Hormone (LH)

Anterior pituitary gonadotropin that triggers a massive preovulatory surge to induce ovulation, converts thecal and granulosa cells into progesterone-producing lutein cells, and supports the corpus luteum.

Estrogen (Estradiol)

Female steroid hormone secreted by ovarian follicles and the corpus luteum that drives endometrial proliferation, stimulates vaginal epithelial growth, develops breast ductal tissue, and mediates positive feedback for the LH surge.

Progesterone

Female steroid hormone secreted by the corpus luteum that converts the endometrium into a secretory structure, increases basal body temperature, and maintains negative feedback on FSH and LH to prevent new follicle recruitment.

Inhibin

Hormone secreted by granulosa and lutein cells that provides selective negative feedback to the anterior pituitary to suppress FSH secretion.

Human Chorionic Gonadotropin (hCG)

Placental hormone secreted during pregnancy that maintains and prolongs the lifespan of the corpus luteum for 2 to 4 months.

Prolactin

Anterior pituitary hormone whose elevated post-partum levels stimulate lactogenesis within the secretory acini of the breast.

Oxytocin

Posterior pituitary hormone that causes myoepithelial cell contraction in the mammary glands, triggering the milk let-down reflex.

Luteinization-Inhibitory Factor

Substance present in follicular fluid that prevents premature luteinization of granulosa and theca cells prior to ovulation.

Granulosa Cells

Ovarian follicular cells surrounding the oocyte that proliferate under FSH stimulation, secrete estrogen-rich follicular fluid into the antrum, express aromatase, and develop LH receptors prior to ovulation.

Theca Cells

Ovarian stromal cells organized into an endocrine theca interna (which synthesizes androgens under LH stimulation) and a vascular connective theca externa capsule.

Zona Pellucida

Glycoprotein membrane formed around the developing oocyte during primary follicle maturation.

Antrum

Fluid-filled cavity within a developing secondary follicle formed by granulosa cell secretion of follicular fluid rich in estrogen.

Graafian Follicle

Fully matured antral follicle containing an enlarged ovum that protrudes against the ovarian surface prior to ovulation.

Follicular Atresia

Degenerative process through which all but one of the recruited follicles regress and die during each menstrual cycle.

Two-Cell, Two-Gonadotropin Model

Biosynthetic pathway where theca cells produce androstenedione and testosterone under LH stimulation, which are then converted to estrogen by aromatase in granulosa cells under FSH stimulation.

LH Surge & Ovulation

Dramatic 6- to 10-fold increase in LH occurring 2 days prior to midcycle that, together with a 2- to 3-fold FSH increase, causes rapid follicular swelling, membrane rupture at the stigma, and release of the mature oocyte on day 14.

Stigma

Swollen, protruding weak point on the outer wall of the preovulatory follicle that bursts during ovulation to release the oocyte.

Corpus Luteum

Temporary endocrine structure formed from converted granulosa and theca cells after ovulation that grows up to 1.5 cm and secretes high levels of progesterone and estrogen.

Corpus Albicans

Fibrotic scar tissue formed approximately 12 days post-ovulation when the corpus luteum involutes due to declining gonadotropin levels.

Cornification & Decornification

Cyclical vaginal epithelial changes where estrogen induces keratinized cell overgrowth post-ovulation, followed by leukocyte invasion and sloughing near the end of the luteal phase.

Basal Body Temperature Shift

Progesterone-mediated thermogenic effect that raises average body temperature above 98°F following the midcycle LH surge.

Menopause

Normal developmental event marking the cessation of menses and reproduction, characterized by ovarian shrinking and depletion of follicles to approximately 1,000.

Primary Dysmenorrhea

Painful menstruation caused by endometrial prostaglandin release during ovulatory cycles, inducing high-frequency uterine contractions, intrauterine hyperpressure, uterine ischemia, and activation of type C pain fibers.

Secondary Dysmenorrhea

Painful menstruation related to underlying pelvic pathological conditions (such as endometriosis or fibroids) occurring later in reproductive life.

Primary Amenorrhea

Absence of menstruation by age 13 in the absence of secondary sex characteristics, or by age 15 regardless of secondary sex development, often caused by gonadal dysgenesis (e.g., Turner syndrome) or Müllerian agenesis.

Complete Androgen Insensitivity Syndrome

Genetic disorder characterized by a 46,XY karyotype and male gonads, but female external phenotypic characteristics due to target tissue androgen unresponsiveness.

Abnormal Uterine Bleeding (AUB)

Bleeding that is abnormal in duration, volume, frequency, or regularity, present for the majority of the preceding 6 months (classified under the PALM-COEIN framework).

Dysfunctional Uterine Bleeding

Heavy or irregular uterine bleeding occurring in the absence of underlying structural pelvic disease, most commonly resulting from perimenopause.

Anovulatory Bleeding Pathogenesis

Pathophysiological mechanism where failure of ovulation prevents corpus luteum formation, leaving unopposed estrogen to continuously proliferate the endometrium until it outgrows its blood supply, causing breakdown and irregular breakthrough sloughing.

Menorrhagia

Abnormally heavy or prolonged menstrual bleeding.

Metrorrhagia

Irregular intermenstrual or midcycle uterine bleeding