Monday 5 September 2011

Menstrual Cycle


Menstrual Cycle

  1. Series of rhythmic reproductive cycle
Ø  From the onset of menstrual bleeding to the next period
Ø  Characterized by changes in the ovaries and uterus
Ø  Influenced by normal hormonal variation mediated by hypothalamus and anterior pituitary gland via feedback mechanism
Ø  Recurring cyclically beginning at puberty with first menstruation called the  MENARCHE and ceasing at MENOPAUSE
Ø  Mean cycle length  of 28 days; normal range 25-28 day per cycle

      B.  Function of the cycle
Ø  In preparation for the release of egg, fertilization and implantation

  1. Hormonal Control of Menstrual Cycle

1.      Follicle Stimulating Hormone (FSH)
Ø  Secreted by the anterior pituitary gland during the first half of the menstrual cycle
Ø  Stimulate the development of graafian follicle
Ø  Thickens the endometrium
      
2.      Luteinizing Hormone (LH)
Ø  Secreted by the pituitary gland
Ø  Stimulates ovulation and development of corpus luteum
Ø  Thickens the endometrium


3.      Estrogen
Ø  Secreted primarily by the ovaries, by the adrenal cortex and by the placenta in pregnancy
Ø  Stimulates thickening of the endometrium causes suppression  of FSH secretion
Ø  Assist in maturation of  ovarian follicles
Ø  Responsible for the development of secondary sex characteristics
Ø  Stimulates uterine contractions
Ø  Mildly accelerates sodium and water reabsorption by kidney tubules; increase water content of the uterus
Ø  High estrogen contraction-inhibits secretion of FSH and prolactin but stimulates secretion of LH
Ø  Low estrogen concentration after pregnancy, stimulates secretion of prolactin
Ø  Accelerates protein anabolism
Ø  Responsible for the fertile cervical mucus; clear, stingy, stretchable, slippery, with fern patterns when dry

4.      Progesterone
Ø  Secreted by corpus luteum and placenta during pregnancy
Ø  Inhibits secretion of LH
Ø  Has thermogenic effect (increases basal body temperature)
Ø  Relaxes smooth muscles
Ø  Responsible for infertile mucus, opaque, sticky, thick, non-stretchable, non-fern pattern when dry
Ø  Maintain thickness of endometrium
Ø   Allows pregnancy to be maintained

5.      Prostaglandin
Ø  Fatty acids categorized a hormone
Ø  Produced by many organs of the body, including the endometrium
Ø  Affects menstrual cycle
Ø  Influences the onset and maintenance of labor

Phases of Menstrual Cycle

       1.  Menstrual Phase (Day 1-5)

a.       Corpus luteum degenerates
b.      There is cessation of progesterone and estrogen produced by corpus       luteum and blood level stops
c.       Endometrium degenerates and menstruation occurs
d.      Drop in blood levels of estrogen and progesterone stimulate production of FSH and new cycle begins

2.      Proliferative Phase (Day 6-14)

a.       Follicle-stimulating hormone (FSH) released by the anterior pituitary stimulates the development 
b.      As graafian follicle develops, it produces increasing amounts of follicular fluid containing a hormone called estrogen
c.       Estrogen stimulates thickening of the endometrium
d.      As estrogen increasing in the bloodstream, it suppresses secretion of FSH and favors secretion of the luteinizing hormone (LH) 
e.       LH stimulates ovulation and initiates development of corpus luteum

3.      Secretory Phase (Day 15-21)

a.       Follows ovulation, which is the release of mature ovum from the graafian follicle
b.      Cavity of the graafian follicle is replaced by the corpus luteum (secretes progesterone and some estrogen)
c.       Progesterone acts upon the endometrium to bring about secretory changes that prepare it for pregnancy. It also maintains the endometrium during the early phase of pregnancy, should a fertilized ovum be implanted

4.      Pre- Menstrual (Day 22-26)

a.       If fertilization does not occur the corpus luteum in the ovary begins to regress
b.      Production of progesterone and estrogen decreases
c.       Endometrium of uterus begins to degenerate and sloughs off
d.      Endometrium becomes thicker and vascular ready for implantation

 4 phases of Menstrual Cycle
1. Phases of Menstrual Cycle:
1. Proliferative
2. Secretory
3. Ischemic
4. Menses

Parts of body responsible for mens:
1.       hypothalamus
2.       anterior pituitary gland – master clock of body
3.       ovaries
4.       uterus
Initial phase – 3rd day – decreased estrogen
13th day – peak estrogen, decrease progesterone
14th day – Increase estrogen, increase progesterone
15th day – Decrease estrogen, increase progesterone
I.         On the initial 3rd phase of menstruation , the estrogen level is decreased, this level stimulates the   hypothalamus to release GnRH or FSHRF
II.                  GnRH/FSHRF – stimulates the anterior pituitary gland to release FSH
Functions of FSH:
1.       Stimulate ovaries to release estrogen
2.       Facilitate growth primary follicle to become graffian follicle (secrets large amt estrogen &  contains mature ovum.)
III.               Proliferative Phase – proliferation of tissue or follicular phase, post mens phase. Pre-ovularoty.
-phase of increase estrogen.

Follicular Phase – causing irregularities  of mens
Postmenstrual Phase
Preovulatory Phase – phase increase estrogen

IV.                13th day of menstruation, estrogen level is peak while the progesterone level is down, these stimulates the hypothalamus to release GnRF on LHRF
1.)     Mittelschmerz – slight abdominal pain on L or RQ of abdomen, marks ovulation day.
2.)     Change in BBT, mood swing

V.                  GnRF/LHRF stimulates the ant pit gland to release LH.
Functions of LH:
1.       (13th day-decreased progesterone) LH stimulates ovaries to release progesterone
2.       hormone for ovulation
        VI. 14th day estrogen level is increased while the progesterone level is increased causing rupture of graffian follicle on process of     ovulation.

        VII. 15th day, after ovulation day, graafian follicle starts to degenerate yellowish known as corpus luteum (secrets large amount of progesterone)

        VIII.               Secretory phase-
Lutheal Phase
Postovulatory Phase Increased progesterone
Premenstrual Phase

         IX. 24th day if no fertilization, corpus luteum degenerate ( whitish – corpus albicans)

         X.    28th day – if no sperm in ovum – endometrium begins to slough off to begin mens

Fornix- where sperm is deposited
Sperm- small head, long tail, pearly white
Phonones-vibration of head of sperm to determine location of ovum
Sperm should penetrate corona radiata and zona pellocida.
Capacitation- ability of sperm to release proteolytic enzyme to penetrate corona radiata and zona pellocida.


Menstrual Disorders

Dysmenorrhea – pain with menses

Types:

Primary – begins 1-3 months after menarche in conjunction with ovulatory cycles
Secondary – suspected when pain is concentrated on a specific area or only on one side when its onset occurs after age 20

Etiology:
Ø  Due to unknown factors
Ø  Thought to be intrinsic to uterus; excessive production of prostaglandins
Ø  Sedentary occupation
Ø  Poor posture
Ø  Poor personal hygiene
Ø  Constitutional illness such as anemia
Ø  Daughter of women who have suffer or have suffered from dysmenorrhea are frequently dysmerrheic

Sign and Symptoms:
Ø  Cramps in the lower abdomen and occasionally into the groin, thigh, and vulva
Ø  Tension
Ø  Nausea and vomiting
Ø  Malaise
Ø  Chills and shivering
Ø  Diarrhea
Ø  Pallor
Ø  Hot and cold sensation
Ø  Fainting in some cases




Treatment and Management

Ø  Explanation or normal and anatomy and physiology of menstruation-serves to eradicate misconception and lessen fear and anxiety which may be associated with her periods

Nursing Management

Ø  Instruction  in menstrual hygiene-so that her period does not seem distasteful and restricting, encourage frequent bathing
Ø  Encourage to get more good posture and exercise particularly aerobics (cycling, jogging, walking, and waist bending before the onset of the period)
Ø  Avoidance over fatigue and overexertion during the period
Ø  Apply heat (e.g. warm baths, putting a hot water bottle, or heating pads on the abdomen)
Ø  Focuses on education and psychosocial needs of the patient
Ø  Encourages to drink plenty of fluids, but avoid alcohol
Ø  Divert attention
Ø  Encourage rest and sleep
Ø  Apply relaxation technique; massage
Ø  Avoid aspirin or prostaglandin inhibitor such as ibuprofen, mefenamic acid-medication are to be taken with water, milk may be used if the medication causes an upset in the stomach
Ø   Usually eliminated by oral contraception which blocks ovulation



1 comment:

  1. I am really happy to say it’s an interesting post to read . I learn new information from your article.thanks for sharing.
    ovarian cycle and menstrual cycle

    ReplyDelete