Menstrual Cycle Review Flashcards
Definition of menarche
1st menstrual period
When is menses expected?
age 14
- no menses by 13 in absence of secondary sex characteristics start workup
- no menses by 15 regardless of development of secondary characteristics evaluate
What is considered a normal cycle length
24-38 days
What is considered a normal duration of flow
8 days or fewer
Define childbearing years
Menarche to menopause
Define perimenopause
Before occurence of menopause
-usually 4 years before
-average age –> 47
Define menopause
1 yr w/o period
- average age –> 51
3 subcycles of menstural cycle
- hypothalamic pituitary cycle (FHS & LH)
- ovarian cycle (estrogen & progesterone)
- Endometrial cycle (menses, follicular, ovulation, luteal)
Role of hypothalamus
secretes GnRH (gonadotropin releasing hormone) in response to decrease estrogen/progesterone from ovaries during menses
Role of anterior pituitary
reacts to stimulation from hypothalamus (GnRH) to secrete FSH (follicle stimulating hormone) and LH (luteinizing hormone) to travel to ovaries
Role of FSH
secreted from anterior pituitary to ovaries to stimulate gorwth of ovarian follicle and promote estrogen & progesterone production & stimulate endometrial growth
Role of LH
secrete from anterior pituitary to ovaries to stimulate growth of selected follicle from FSH (aka stimulate ovulation)
- responsible for corpus lutem development after ovulation
- production of progesterone
How are menstural cycles affected by hypothalamus
dysregulation in hypothalamus can interrupt menstrual cycle
- stress, eating disorders, excessive exercise interfere w/ hypothalamus ability to stimulate pituitary
- can effect fertility
What is the most constant phase of mensutral cycle
Luteal phase (14 days)
How long does ovum and sperm live
ovum: 24 hrs
sperm: 3-5 days
