Menstrual Cycle,Periods Full Discussion

Menstrual Cycle / bleeding cycle/ Periods

Menstrual Cycle

Normal menstrual cycle =eumenorhoea

We will read here:-

  1. Definition
  2. Criteria
  3. Important point
  4. Changes during menstrual cycle
  5. Hormone regulation in menstrual cycle

1.Definition– it is the visible manifestation of cycling physiological uterine bleeding due to shedding of endometrium outflow through vagina follow by invisible interplay of hormone mainly by hpo axis repeated after 28 days



GNRH (Gonadotropin-releasing hormone)

act on anterior pituitary

Gonadotropin hormone release-(FSH) follicle stimulating hormone and (LH) Lutilising hormone

act on ovary

oestrogen and progesterone


  • Hpo axis must be actively cordinated
  • Endometrium must be responsive ovarian hormone
  • Outflow track must be patent (open)

Cryptomenorrhea– menstrual blood collect in uterus, and not excreat out the world through the vagina maybe cause of vaginal tubeblockeg(vaginal atresia) or agenesis of vagina-lack of develop of vagina “

3.Important point


Gradual development of secondary sexual character childhood convert into adulthood age of puberty

In female 10 to 16 years

In male 12 to 16 year

Turner and Marshall 5 stages of puberty

  1. Breast development-first sign of puberty that is thelarchae
  2. Axillary hair -adrenarchy
  3. Pubic hair- pubarchae
  4. Increase height -age up to

In female- age upto 18

In male- age upto 22

  1. 1st menstrual cycle – menarche(Last sign of puberty)


1st menstrual cycle (menarche)

Peak age-13yr

  • menopause(Age 45-55yr)-Permanent stoppage of menstrual cycle
  • Reproductive age(child bearing age) -15 to 45 years (30 year)
  • Duration of menstrual cycle(1 period) -28 days
  • 13 menses in a year
  • 400 menses in reproductive life
  • 20-80 ml blood losh in menstrual cycle (periods)
  • Bleeding Phase -1 to 5 days
  • Bleeding duration -2 to 7 days
  • Average blood loss -35 ml

20 week female foetus- 7 million follicles

At birth -2 million follicles

Upto puberty- 4 lakh follicles

Menopause -_> 10,000 follicles

Menstrual blood do not clot because the blood contain clause plasmin (it is a protein componant)

Dark red waste blood it contain

  • Dead endometrium cell
  • Mucus
  • Prostaglandin (PG)-Local hormone of body(PG) -work (uterine contraction)

Microorganism with normal body temperature <100.4°f

Menstrual cycle repeat if female is not pregnant continuation of Astral cycle indicate that female is not pregnant absence of menstrual cycle indicate female may be pregnant

4.changes during menstrual cycle ovarian changes uterine changes

Ovarian changes  Uterine changes
i Follicular phase


ii luteal phase

i Menstural phase

ii proliferative phase

iii secretory phase of


A. Ovarian changes

Menstrual Cycle
menstrual cycle digram

(i) Follicular phase – up to 14 days

growth of follicle -immature follicles convert into mature follicles

immature follicles convert into mature follicles in the presence of FSH

first discovered by Dutch saints,Holland

(FSH) follicle stimulating hormone by anterior pituitary

One dominant follicle grow faster than other follicles

Flow chart

Graafian follicle produce oestrogen hormone

                                                 – Negetive feedback

Oestrogen decrease the release of FSH

oestrogen increase the release of LH

Graafian follicle rupture


                                                                 in prengence of LH(14 days)


” when ovulation -14 days before next menstrual cycle

peak value of LH – 36 hrs before ovulation

peak value of FSH- 32-48 hrs before ovulation

peak value of oestrogen-36hrs before ovulation “

(ii) luteal phase -15 to 28 days

(Second half of menstrual cycle)

constant phase of menstrual cycle

formation of Corpus luteum

ruptured pieces of follicle yellow colour

function- secretion of hormones

large quantity of progesterone

features of Corpus luteum-

If Fertilization not takes place


Corpus luteum changing into Corpus luteum menstrualis


Corpus luteum albicans


disappear to 26 to 28 days


first day bleeding


if fertilization takes place


Corpus luteum convert into Corpus luteum verum


continue till 3 month up to formation of placenta


disappear after 3 month

B. Uterine changes

Menstrual Cycle
uterine menstrual cycle


1. Menstrual phase (1 to 5 day)

menstrual phase/ bleeding phase /menses /period/ catamenia

uterine menstrual
uterine menstrual

menstrual phase/ Bleeding phase (1 to 5 days)

26 to 28 days Corpus luteum disappear

decrease oestrogen

  • .vasocontraction( contraction of uterine artery)
  • (Infactio is tissue death)
  • ischemia-Lack of blood supply to uterus
  • ischemia cause of hypoxia
  • hypoxia cell death necrosis in reversible cell injury ischemia necrosis


shedding of Dead endometrium cells


blood vessels open


uterine bleeding


collection of blood in uterus( hematometra)


stimulant nerve supply of uterus


sensation transfer to hypothalamus


act on posterior pituitary


release Oxytocin hormone


act on myometrium


uterine contraction


excretion of menstrual blood

At the end of bleeding phase the thickness of endometrium 1 mm

Normal thickness 5 to 6 mm


2 Proliferative phase 6 to 14 days

Follicular phase in ovary


growth of follicles




act on endometrium

                                                                   ↓ endometrium responsive for ovarian hormone


hyperplasia ( proliferation of endometrium cell) increase number of cell


at the end of stage thickness of endometrium 2 to 3 mm


secreatory phase 15 to 28 days

                                                                         + with

luteal phase


formation of Corpus luteum


secretion of oestrogen and progesterone


act on endometrium

oestrogen- hyperplasia( increased number of cell )

progesterone- hypertrophy( increase size)


at the end of this phase thickness of endometrium 5 to 6 mm


endometrium is prepare for next menstrual cycle

if fertilization do not occur menstrual cycle

and prepare for implantation this is proliferative phase


5.Hormone regulation in menstrual cycle

Menstrual Cycle
menstrual cycle periods

Secretion function of Corpus luteum create oestrogen progesterone and regulation of FSH and LH

  1. Follicular phase -FSH
  2. ovulation -LH

FSH and LH=1:1

Serum FSH and LH in blood – 5-20mIu /ml

3. Luteal phase in ovary

FSH & LH stimulate to oestrogen

4.Bleeding phase

Decrease oestrogen

5.Proliferative phase (uterus) 6 to 14 days

decrease Oestrogen

6,Secretory phase (15 to 28 day )

oestrogen + progesterone( preparation for next menstrual cycle)

Mittle schmerz sign-Pain during ovulation ( lower abdomen pain)

An abnormality is related with the menstrual cycle
  1. Amenorrhea -absence of menstrual cycle (physiological or pathological)
  2. Dysmenorrhea – pain during menstrual cycle ,pain during bleeding
  3. Hypermenorrhea – excessive bleeding either in amount (>80ml)

or in duration(>7days)

Treatment-hormonal therapy (oestrogen and progesterone)

4. polymenorrhea /epimenorrhea- menstrual cycle reduced up to 21 days and remain constant at the frequency

ovulation -7 days of menstrual cycle count of menstrual cycle increase

in one year and blood loss per year increase

5. Oligomenorrhea – National cycle explained up to 35 days days of our nation is 35 -14=21day

Number of menses in a year- 10


6. Hypomenorrhea– scanty blood loss <21ml

duration-1days (<2)

7. metrorrhagia– irregular acyclic uterine bleeding

when cycle so much in regular then the menses cannot be count


8. PMS (premenstrual cycle)– psychosomatic disorder of unknown etiology the symptom of which appears in luteal phase and rest of cycle is symptom free

Symptoms- breast tenderness, abdominal distension, nausea vomiting, Insomnia headache, irritable, depression


Tab danazol – to produce amenorrhea(after under doctors observation)

And synonymtic treatment

“avoid painkiller analgesic in periods pain/menstrual pain”


“control unwanted pregnancy and control population”

safe period
safe period

use condoms – prevention for sexual disease