The menstrual cycle is the regular natural change that occurs in the female reproductive system, controlled by hormones. It involves the development and release of an egg (ovulation), as well as thickening of the uterine lining to prepare for pregnancy. If the egg is not fertilized, the uterine lining sheds through menstruation, beginning a new cycle. The typical cycle lasts 28 days and includes the menstrual, follicular, ovulation, and luteal phases. During ovulation, an egg is released and can be fertilized for up to 24 hours.

1. MENSTRUAL CYCLE
ZARAFSHAN ZEB
HUMAN NUTRITION
1Saturday, November 16, 2019

2. MENSTRUAL CYCLE
Definition:
The menstrual cycle is the regular natural change that occur in the female
reproductive system (specially the ovaries and uterus) that makes pregnancy
possible.
 This cycle is controlled by hormones, The menstrual cycle occurs because of a
complex relationship between hormones from the brain and ovaries.
2

3. CONT.
This leads to the development and release of an egg from the ovary (ovulation)
and growth of the internal lining (endometrium) of the uterus, to prepare it for
pregnancy.
 The first period usually begins between 12 and 15 years of age, a point in time
known as menarche (The first menstrual cycle, or first menstrual bleeding, in
female humans).
3

4. THE CALENDAR METHOD OF BIRTH CONTROL
Calendar based contraceptive
methods prevent pregnancy by monitoring
the fertile periods during the menstrual cycle.
Consider the first day of menstrual bleeding as
day one of the menstrual cycle.
Avoid unprotected sexual intercourse between
days 8-19 of the menstrual cycle, as this is the
period of fertility. Women using the standard
days method who wish to have sex in this period
should use another method of contraception. 4

5. VAGINAL STRUCTURE
5

6. MENSTRUAL CYCLE
 From both social and medical perspectives, it is often considered the central event of
female puberty (the process of physical changes through which a child's body matures
into an adult body capable of sexual reproduction) as it signals the possibility of fertility.
SYMPTOMS: Common symptoms include:
tender breasts bloating
painful breasts
acne and spots
headaches
diarrhea
constipation
nausea
dizziness 6

7. MENSTRUAL CYCLE
DURATION:
 The menstrual cycle begins at menarche (the first period) and ends
with menopause (the final period).
 Every woman's cycle is unique and individual.
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 35
days in adults (an average of 28 days).
7

8. PHASES OF MENSTRUAL CYCLE
There are four phases of menstrual cycle……….
1) Menstrual phase
2) Follicular phase
3) Ovulation phase
4) Luteal phase
8

9. MENSTRUAL CYCLE
9

10. MENSTRUAL PHASE
Menstrual phase start on the first day of menstrual cycle
during this phase bleeding start - with the resulting blood
loss.
Most of the bleeding happens during the first three days of
this phase.
You may also experience period pain, which can involve
cramping, dull aches or severe pain, which can also radiate
into your lower back and legs.
10

11. CONT.
Estrogen (Estrogen, or oestrogen, is the primary female sex hormone. It is
responsible for the development and regulation of the female reproductive
system and secondary sex characteristics) and progesterone(progestogen sex
hormone involved in the menstrual cycle, pregnancy, and embryogenesis of
humans and other species)
levels become very low and from day one brain starts to produce Follicle
Stimulating Hormone (FSH) in the pituitary gland, due to which ovaries
producing start a new mature egg.
11

12. MENSTRUAL PHASE
12

13. FOLLICULAR PHASE
During this phase hypothalamus(It is a portion of the brain that link the nervous
system to the endocrine system via the pituitary gland)sends a signal to pituitary
gland to release follicle-stimulating hormone (FSH).
 This hormone stimulates ovaries to produce about 5 to 20 small sacs called
follicles.
Each follicle contains one immature egg.
Only the healthiest egg will eventually mature (On rare occasions, a woman may
have two eggs mature) The rest of the follicles will be reabsorbed into the body.
13

14. CONT.
The maturing follicle sets off a surge in estrogen that thickens the lining of
uterus.
This creates a nutrient-rich environment for an embryo to grow.
The average follicular phase lasts for about 16 days.
It can range from 11 to 27 days, depending on your cycle.
14

15. FOLLICULAR PHASE
15

16. OVALUATORY PHASE
Rising estrogen levels during the follicular phase trigger pituitary gland to
release luteinizing hormone (LH).
 This is what starts the process of ovulation.
Ovulation is when ovary releases a mature egg.
The egg travels down the fallopian tube toward the uterus to be fertilized by
sperm.
The ovulation phase is the only time during menstrual cycle when a women can
get pregnant.
16

17. CONT.
The symptoms are:
a slight rise in basal body temperature
thicker discharge that has the texture of egg whites
Ovulation happens at around day 8-19 in a 28-30 days cycle , right in the middle
of menstrual cycle.
It lasts about 24 hours. After a day, the egg will die or dissolve if it isn’t
fertilized.
17

18. OVALUATORY PHASE
18

19. LUTEAL PHASE
During ovulation, the egg bursts from its follicle, but the ruptured
follicle stays on the surface of the ovary.
For the next two weeks or so, the follicle transforms into a structure
known as the corpus luteum.
This structure starts releasing progesterone, along with small
amounts of oestrogen.
The cells of the corpus luteum produce estrogen and large amounts of
progesterone.
19

20. CONT.
Progesterone stimulates your uterine lining to prepare for a fertilized egg.
Here’s where two things can happen.
1. If you become pregnant, the egg moves into your uterus and attaches to the
lining.
2. If you are not pregnant, the lining of the uterus is shed through the vaginal
opening. Your period starts and a new menstrual cycle begins.
20

21. LUTEAL PHASE
21

22. REFRENCES
Silverthorn, Dee Unglaub (2013). Human Physiology: An Integrated Approach (6th ed.).
Glenview, IL: Pearson Education. pp. 850–890. ISBN 0-321-75007-1.
 Sherwood, Laurelee (2013). Human Physiology: From Cells to Systems (8th ed.). Belmont,
California: Cengage. pp. 735–794. ISBN 1-111-57743-9.
 Office of Women's Health, USA. 23 December 2014. Archived from the original on 26 June
2015. Retrieved 25 June 2015.
22

23. 23