Menstruation is the monthly discharge of blood and tissues from the uterus through the vagina in non-pregnant women. It typically begins during adolescence between ages 12-15 and occurs about every 21-31 days. Menstruation stops during pregnancy, breastfeeding, and after menopause. The menstrual cycle involves both ovarian and uterine cycles regulated by hormones like estrogen and progesterone produced by the ovaries and hypothalamus/pituitary gland. When fertilization does not occur, decreasing progesterone triggers menstruation and the start of a new cycle. Imbalances in hormones like estrogen and progesterone can cause various symptoms.

1. MENSTRUATION

2. Female Reproductive System
External organs

3. Internal organs

4. DEFINATION
• Menstruation, also known as a period or
monthly, is the regular discharge of blood
and mucosal tissue from the inner lining of
the uterus through the vagina.

5. • The first period usually begins between twelve
and fifteen years of age, a point in time known as
menarche.
• The typical length of time between the first day of
one period and the first day of the next is 21 to 45
days in young women, and 21 to 31 days in adults
(an average of 28 days).
• Bleeding usually lasts around 2 to 7 days.
• Menstruation stops occurring after menopause,
which usually occurs between 45 and 55 years of
age. Periods also stop during pregnancy and
typically do not resume during the initial months
of breastfeeding.

6. PHASES OF MENSTRUATION

7. A) Ovarian cycle
• 1) Follicular Phase
The follicular phase is the first part of the ovarian
cycle. During this phase, the ovarian follicles
mature and get ready to release an egg.The latter
part of this phase overlaps with the proliferative
phase of the uterine cycle.

8. • 2) Luteal Phase
The luteal phase is the final phase of the ovarian
cycle and it corresponds to the secretory phase of
the uterine cycle.
The pituitary hormones FSH and LH cause the remaining
parts of the dominant follicle to transform into the corpus
luteum
produces progesterone.
The increased progesterone in the adrenals starts to induce
the production of estrogen.

9. The hormones produced by the corpus luteum also suppress
production of the FSH and LH that the corpus luteum needs to
maintain itself.
the level of FSH and LH fall quickly over time and the corpus
luteum atrophies.
Falling levels of progesterone trigger menstruation and the
beginning of the next cycle.
From the time of ovulation until progesterone withdrawal has
caused menstruation to begin, the process typically takes about
two weeks, with 14 days considered normal. For an individual
woman, the follicular phase often varies in length from cycle to
cycle; by contrast, the length of her luteal phase will be fairly
consistent from cycle to cycle.

10. B) Uterine Cycle

11. 1) Proliferative phase
• The proliferative phase begins at the end of menstruation and
lasts until ovulation,which is about 10 days.
• In this time the anterior lobe of the pitutary gland produces
an increased amount of FSH.
• This hormone plays a major role in the maturation of the
single ovum but sometimes two or more may do so.
• While the FSH prepares the ovum to become mature, in the
mean time, estrogen affects the lining of the endometrium.
• The hormone passes directly into the blood stream and has its
effect upon the endomatrium, stimulating the columnar cells
to reproduce the endomatrium more rapidly forming a thicker
lining and increasing number of glands and blood capillaries
cause more vascular and spongy.

12. • In this phase the endometrium become 2-3 mm
thick to recieve the fertilized ovum.
• Rising blood levels of oestradial exert negative
feedback on FSH secretion and positive feedback
on LH secretion.as a result of a surge in the LH
level,ovulation occurs.
• Ovulation is a process whereby a secondary oocyte
is released from the ovary following rupture of a
mature graafian follicle and becomes available for
conception.
• The ovum remains viable for 24-72 hours.
• After ovulation this phase is complete.

13. 2)Secretory Phase
• This phase begins just after ovulation and lasts for about 2
weeks.
• In this phase there is an increase in the secretion of LH by
anterior pituitary gland,a temporary endocrine gland called
corpus luteum is formed from the ruptured follicle.
• The ruptured follicle filled with a yellow substance known as
luteum.
• Under the influence of LH ,the corpus luteum produced
second ovarian hormone especially progesterone hormone.
• This hormone is directly absorbed into the blood stream and
cause the further thickening of the endometrium lining,so the
endometrium becomes highly vascularized,thick and spongy
for the reception of the fertilized ovum.

14. • The endometrial glands become enlarged and secrete
glycogen and mucin,which is essential for the nourishment
of the ovum,if fertilized.
• However if the ovum is not fertilized the size of the corpus
luteum shrinks and the progesterone level in blood is
decreased.because of this the endometrium ceases to grow
further and the menstrual phase begins again.
• IN FERTILIZED, there is no menstrual flow and now the
endometrium is called decidua where the fertilized ovum
embeds.
• Then it produces the human chorionic gonadotrophin
hormone,which keep corpus luteum intact and thus allow is
to continue secreting progesterone.
• IF THE OVUM IS NOT FERTILIZED,then menstrual
bleeding begins.

15. 3)Menstrual Phase
• If the ovum is not fertilized,the progesterone level in blood is
decreased which causes shrink and degeneration of the
corpus luteum.
• As a result of decreased oestrogen and progesterone level in
blood,the superficial layer of the endometrium is shed and
the blood discharge from the vagina follows.
• This lasts for about 4-6 days.
• The normal amount of blood flow at each cycle is
approximately 60-90 ml.
• When the progesterone level in the blood falls to a certain
level the pituitary gland again starts to secrete

16. Hormonal control on menstruation
• 1. FHS: follicular stimulating hormone -causes
growth of follicles in the ovaries prior to
ovulation.
• 2. LH: leutinizing hormon- plays an important
role in causing ovulation and also promotes
secretion of female sex hormones by the
ovaries.
• 3. HCG: human chorionic gonadotrophin-
promotes growth of corpus leutium and
secretion of estrogen and progesterone by
the same.

17. • 4. Estrogen (estradiol )- stimulate the
development of female sex organs, the
breast and other secondary sexual
characteristics.
• 5. Progesterone (progestin)- stimulates
secretion by uterine endometrial glands in
preparation for implantation, otherwise
know as decidual reaction. It also helps to
promote the development of the Secretary
apparatus of breast.

18. Hypothalamo-pituitary-ovarian-axis.

19. • The regulation of the menstrual cycle is due to the
hormonal integrated functioning of the
hypothalamo-pituitary-ovarian-axis.
• The hypothalamus and the pituitary are stimulated
in the human brain and effect the production of
releasing hormones which induce the end organ-
ovaries to release the primary female hormones
namely estrogen and progesterone. This is called
positive feedback.
• When the level of these hormones have reached an
adequate level to perform their respective
functions, they suppress the releasing effect in the
brain. This is called negative feedback.

20. Imbalance in Hormones
1. Progestrone
•Low progesterone causes
Possible miscarriage
Menopause

21. • Low progesterone symptoms
Hot flashes
Libido
Migraines or headaches
Depression, anxiety or other mood changes
Menstrual cycle irregularity or absence
Spotting
Abdominal pain
Frequent low blood sugar
Regularly tender breasts
Constant fatigue
Vaginal dryness

24. 2) Estrogen
• Symptoms Of Low Estrogen Levels
• Hot flashes
• Mood swings
• Depression
• Headaches (or even migraines)
• Fatigue
• Issues with concentration and focus
• Irregular or even absent periods
• Urinary tract infections
• Painful sex
• Irregular periods
• Infertility
• Weak bones
• Painful intercourse
• Increase in urinary tract infections

25. • Symptoms of high estrogen in women
• bloating
• swelling and tenderness in your breasts
• fibrocystic lumps in your breasts
• decreased sex drive
• irregular menstrual periods
• increased symptoms of premenstrual syndrome (PMS)
• mood swings
• headaches
• anxiety and panic attacks
• weight gain
• hair loss
• cold hands or feet
• memory problems

27. Summary