Female Cycle Ch 20

Front 1

the cycle is regulated by complex hormonal interactions

Back 1

estrogen secreting follicle in first half of cycle and progesterone + estrogen secreting corpus luteum in last half of cycle

Front 2

each unit is triggered by cyclical hormonal changes among hypothalamus, anterior pituitary, and the ovarian endocrine units themselves (---and---)

Back 2

(follicle and corpus luteum)

Front 3

gonadal function directly controlled by anterior pituitary gonadotropic hormones:

Back 3

FSH ( follicle stimulating hormone) and LH (luteinizing hormone). these are controlled by GnRH (gonadotropin-releasing hormone) and feedback from gonadal hormones.

Front 4

after the onset of puberty, the ovary constantly alternates between two phases:

Back 4

the follicular phase, which is dominated by the presence ofmaturing follicles, and the luteal phase, which is characterized by the presence of the corpus luteum.

Front 5

this cycle is normally interrupted only by pregnancy and is finally terminated by menopause.

Back 5

the average ovarian cycle lasts 28 days

Front 6

the follicle operates in the first half of the cycle to produce a mature egg ready for ovulation at midcycle.

Back 6

the corpus luteum takes over during the last 14 days of the cycle to prepare the female reproductive tract for pregnancy if fertilization of the released egg occurs.

Front 7

at any given time throughout the cycle, a portion of the primary follicles is starting to develop. however, only those that do so during the follicular phase, when the hormone environment is right to promote their maturation, continue beyond the early stages of development

Back 7

the others, lacking hormonal support, undergo atresia

Front 8

during the follicular phase the granulosa cells of some primary follicles proliferate

Back 8

oocytes inside each follicle enlarges. thecal an granulosa cells, collectively called follicular cells, secrete increased amounts of estrogen, which circulates throughout the body

Front 9

rapid follicular growth continues during the follicular phase

Back 9

one follicle usually grows more rapidly and matures about 14 days after the onset of follicular development. this follicle rupturesto release the oocyte fro the ovary = ovulation. then the oocyte enters the oviduct where it may or may not be fertilized.

Front 10

luteal phase: corpus luteum dominates the last 14 days of the cycle

Back 10

corpus luteum = converted follicular cells left behind in the ovary after ovum (secondary oocyte) is ovulated

Front 11

corpus luteum secretes more

Back 11

progesterone compared to follicular phase

Front 12

corpus luteum also secretes

Back 12

estrogen

Front 13

corpus luteum degenerates 14 days after its formation unless fertilization and implantation occur

Back 13

if fertilization occurs, corpus luteum continues to secrete hormones and is then called the corpus luteum of pregnancy

Front 14

follicular phase: a rise in FSH signals the ovarian follicle to secrete more estrogen

Back 14

this rise in estrogen feed back to inhibit FSH secretion , which declines as the follicular phase proceeds.

Front 15

follicular phase cont: LH rises and peaks mid cycle, triggering ovulation. estrogen output decreases and the mature follicle is converted to a corpus luteum

Back 15

follicular phase over

Front 16

luteal phase: corpus luteum secretes estrogen and progesterone

Back 16

progesterone output inhibits the release of FSH and LH. low LH results in corpus luteum degeneration. corpus luteum degeneration causes progesterone levels to decline. FSH can start to rise again, initiating a new cycle.

Front 17

follicular phase-->ovulatin--->luteal phase--->new follicular phase--->

Back 17

fluctuating estrogen and progesterone levels produce cyclical changes in the cervical mucus

Front 18

menopause is unique to females

Back 18

mid-life hypothalamic change may cause the onset of menopause. it is characterized by increasingly irregular cycles and dwindling estrogen levels

Front 19

pubertal changes in females and males are similar

Back 19

GnRH secretion increases at the onset of puberty and GnRH stimulates hormonal release from the anterior pituitary

Front 20

increased conc. of estrogen right before ovulation --> day 14 most fertile--->clear and thin mucus helps sperm reach destination-->then progesterone--->causes mucus to be thick and sticky--->causes plugging of uterus which is good for conception

Back 20

COC= combination oral contraceptives . they contai both estrogen and progestin

Front 21

the formulation sof COC vary: monophasic, biphasic, and triphasic

Back 21

monophasic: contain same dose of estrogen and progestin for 21 days, followed by 7 days of no steriods

Front 22

biphasic and triphasic contain varying amounts of each

Back 22

monophasic coc effects:
suppressed LH due to negative feedback, suppressed FSH due to negative feedback, LH surge does not occur because the exogenous steriods eliminate positive feedback of estrogen, ovulation s inhibited due to lack of LH surge, endogenous steroid hormones decrease, GnRH is suppressed due to negative feedback, and cervical mucose is thickened due to progestin and lack of high estrogen conc.