Physiology of Menstruation
Email This Post
· 
Print This Post
Menstruation - is the periodic discharge of blood, mucus and epithelial cells from the uterus.
Menstrual Cycle – periodic uterine bleeding in response to cyclic hormonal changes. A process that allows for conception and implantation of new life.
It is usually determined by counting as day 1 the 1st day of a menstrual period until the last day before the next menstrual period.
Purpose:
- To bring an ovum to maturity
- To renew a uterine tissue bed that will be responsive to fetal growth
- To prepare the uterus for pregnancy
Characteristics of Normal Menstrual Cycles
|
TERM |
DESCRIPTION |
| Beginning (Menarche) | average age of onset: 12 or 13 years; average range of age: 9-17 years |
| Interval between cycles | average 28 days; cycles of 23 to 35 days not usual |
| Duration of Menstrual flow | average flow: 2-7 days; ranges 1-9 days not normal |
| Amount of menstrual flow | difficult to estimate; average 30 to 80 ml. per menstrual period; saturating a pad in less than an hour is considered heavy bleeding. |
| Color of menstrual flow | dark red; a combination of blood, mucus, and endometrial cells |
| Odor of menstrual flow | marigold |
Discomforts of Menstruation
- Breast tenderness and feeling of fullness
- Tendency towards fatigue
- Temperament and mood changes – because of hormonal influence and decreased levels of estrogen and progesterone
- Discomfort in pelvic area, lower back and legs
- Retained fluids and weight gain
Abnormalities of Menstruation
- Amenorrhea – absence of menstrual flow
- Dysmenorrhea – painful menstruation
- Oligomenorrhea – scanty menstruation
- Polymenorrhea – too frequent menstruation
- Menorrhagia -excessive menstrual bleeding
- Metrorrhagia – bleeding between periods of less than 2 weeks
- Hypomenorrhea – abnormally short menstruation
- Hypermenorrhea – abnormally long menstruation
Four body structure involved in the physiology of the menstrual cycle:
- Hypothalamus
- Pituitary gland
- Ovaries
- Uterus
Reproductive Hormones:
- Gonodotropin-Releasing Hormone (GnRH)
- Stimulates release of FSH and LH initiating puberty and sustaining menstrual cycle.
- Follicle-stimulating Hormone (FSH)
- secreted by anterior pituitary gland during the 1st half of menstrual cycle
- stimulate growth and maturation of graafian follicle before ovulation
- thins the endometrium
- Luteinizing Hormone (LH)
- secreted by the anterior pituitary gland
- stimulates final maturation of graafian follicle
- surge of LH about 14 days before next menstrual period causes ovulation
- stimulates transformation of graafian follicle into corpus luteum
- thickens the endometrium
- Estrogen
- secreted primarily by the ovaries, corpus luteum, adrenal cortex and placenta in pregnancy
- considered the Hormone of Women
- stimulates thickening of the endometrium; causes suppression of FSH secretion
- responsible for the development of secondary sex characteristics
- stimulates uterine contractions
- increases water content of uterus
- high estrogen concentration inhibits secretion of FSH and Prolactin but stimulates secretion of LH7.
- low estrogen concentration after pregnancy stimulates secretion of Prolactin
- Progesterone
- secreted by the ovary, corpus luteum and placenta during pregnancy
- inhibits secretion of LH
- has thermogenic effect (increases body temperature)
- relaxes smooth muscles thereby decreases contractions of uterus
- causes cervical secretion of thick mucus
- maintain thickness of endometrium
- allows pregnancy to be maintained = Hormone of Pregnancy
- prepares breasts for lactation
- Prolactin
- secreted by the anterior pituitary gland
- stimulates secretion of milk
- Oxytocin
- secreted by the posterior pituitary gland
- stimulates uterine contractions during birth and compress uterine blood vessels and control bleeding
- stimulates let-down or milk-ejection reflex during breastfeeding
- Prostaglandins
- fatty acids’ categorized as hormones
- produced by many organs of the body, including the endometrium
- affects menstrual cycle
- influences the onset and maintenance of labor
Advertisements:
No related posts.
Find Your Nursing Topic:
7 Responses for “Physiology of Menstruation”
Leave a Reply
DISCLAIMER: Comments expressed in this website are those of the readers and do not necessarily reflect the position of NursingCrib.com or any of its sister sites. NursingCrib.com does not knowingly publish false information and may not be held liable for the views of readers exercising their right to free expression.
All articles in this site was meant for educational purposes only. We don’t claim full ownership of the videos, pictures and some articles posted on this site. All other trademarks are the property of their respective owners.
Loading ...
Dear Admin,
Thank you so much for educating us more! You provide us with good info and with matching illustrations.
You’re such a wonderful guys…God bless all of you !!!
sana mas madami pang ma-post d2.. para d n kelangan magbasa ng book.. hehe…
example, about labor and delivery, complications, mechanism… un… hehe
tnx poh
Ihondon, you’re more than welcome. Glad to be of service ;)
helow poh…tnx for the discussion of your topic about menstruation..it helps me in explaining to my patient nd frends that approach me….im a nurse thats why i nid to jnow that….tnx po tlaga sa nilagy nyo na unfamiliar terms about menstruation…..
Hi mj, nice suggestion. Next time we will do whatever it takes to complete our posts. We do encourage all suggestions (positive and negative) so that we can improve this site. Thanks for the comment. :)
it would have been better if the stages or phases of menstruation as well as the mechanisms and physiology in each stage were included though i don’t frantically expect it to be too detailed. just a short discussion of it would do.
Buenas gratias amigo y amiga!
ohh nursingcrib.com you always feed my mind.thank so much for being so informative.
grabeeeee—-i remember sa anatomy namin–my nose bleed.and honestly,madami na ko nakalimutan–but thru the help of nursing crib.com madali ko ma recall.
more powerrrrrrr po.Merci-domo arigato guzaimazu!
*malou*