This document discusses the menstrual cycle and related topics. It begins by listing learning objectives about defining terminology, identifying cycle characteristics and phases, describing hormonal changes, and discussing conception and pregnancy signs. It then defines key terms and describes the typical length, timing, and phases of the menstrual cycle including the follicular, ovulation, and luteal phases. It discusses the ovarian and uterine cycles, basal body temperature, the development of the conceptus, and common disorders of the menstrual cycle.

1. Objectives
At the end of this session the students will be able to:
 Define the terminology related to the menstrual cycle.
 Identify the characteristics of menstrual cycle.
 Discus the phases of Ovarian cycle
 Describe the hormonal changes during each phase.
 List the phases of the menstrual cycle.
 Identify the disorders of Menstrual cycle.
 Discus the process of conception.
 Illustrate the diagnostic signs of pregnancy.
 Identify factors may improve the chances of conception.
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2. Terminology
 Menarche: is the age of the first menstrual cycle
and culminates at the age of puberty.
 Menstruation: is the cyclic vaginal discharge of
blood and denuded tissue.
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3. The mean duration of the MC:
• Mean 28 days (only 15% of ♀)
• Range 21-35 days
 The average duration of menses:
3-7 days
 The normal estimated blood loss:
•Approximately 30-80 ml
 Ovulation occurs on day 14
The mean age of menarche & menopause:
• Menarche 12 yrs
• Menopause 51 yrs
Length and Timing of the menstrual Cycle
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4. Ovarian Cycle
Monthly series of events associated with the
maturation of an egg & Ovarian cycle divided into
three phases:
1. Follicular Phase
2. Ovulation
3. Luteal Phase
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6. 1. Follicular Phase
 The follicular phase starts with the development of about 20
Graafian follicles in the ovary under the stimulation of the
hormone FSH released from the pituitary gland. These
follicles grow steadily, releasing the hormone ‘oestrogen’ into
the blood stream.
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7.  At around the 10th day of the follicular phase, one of the
follicles becomes distinctly larger than the others. It continues
to grow, becoming larger and larger (‘dominant follicle’) to
become mature, while the growth of the others are arrested.
These eventually die out.
 The oestrogen released by the follicles, acts on the
endometrium of the uterus and stimulates it to proliferate,
indicating the start of the uterine cycle. The proliferative phase
is thus also called the oestrogenic phase
1. Follicular Phase cont..
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8. 9

9. 2. Ovulation
 Ovulation occurs (Midcycle) when the ovary
wall ruptures and expels the secondary oocyte
- pain sometimes felt at ovulation
 1-2% of ovulations release more than one
secondary oocyte, which if fertilized, results in
twins
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10. 3. Luteal Phase
 Luteal phase extends from day 15 to the end of the
cycle, day 28
 After ovulation, the ruptured follicle collapses,
granulosa cells enlarge and form the corpus luteum
 The corpus luteum secretes progesterone and
estrogen
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11. If pregnancy does not occur, the corpus luteum
degenerates in 10 days, leaving a scar (corpus
albicans)
If pregnancy does occur, the corpus luteum
produces hormones until the placenta takes over that
role (at about 3 months)
3. Luteal Phase
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12.  Basal Body temperature is the lowest temperature
that your body reaches during each 24-hour day &
usually reached during deep sleep and then increases
as you wake up.
 BBT is the oldest method of fertility monitoring.
Women’s BBT are biphasic i.e. the temperatures taken
in the phase before ovulation are lower than those
taken in the phase after ovulation.
Basal Body Temperature (BBT)
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13.  During the first phase of your cycle, high levels
of oestrogen in your body keep temperatures low.
Your raised BBT after ovulation is due to the level
of progesterone in your body. Progesterone is
secreted by the corpus luteum (the empty egg sac
that the egg emerges from) and indicates that you
have ovulated.
Basal Body Temperature (BBT) cont…
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14. 15

15. Ovary, Tubes and Uterus
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16. Uterine Wall
 Composed of three layers:
 Perimetrium – outermost serous layer; the
visceral peritoneum
 Myometrium – middle layer; interlacing layers
of smooth muscle
 Endometrium – mucosal lining of the uterine
cavity
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17. Menstrual/uterine Cycle
Series of cyclic changes that the uterine
endometrium goes through each month in
response to ovarian hormones in the blood.
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18. Phases of Menstrual/Uterine Cycle
1. Proliferative Phase
2. Secretory Phase
3. Menstrual Phase
1. Proliferative Phase: Preparing
for Ovulation - endometrium
begins to grow after menstruation.
2. Secretory Phase: Preparing for
Implantation - endometrium is
becoming ready for the
implantation of a blastocyst.
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19. Normal Menstrual Cycle
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20. Phases of Menstrual/uterine Cycle
3. Menstrual Phase
 If fertilization does not occur, progesterone levels
fall, depriving the endometrium of hormonal
support
 Spiral arteries kink and go into spasms and
endometrial cells begin to die
 Spiral arteries constrict one final time then
suddenly relax and open wide
 The rush of blood fragments weakened capillary
beds.
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21. 1. Dysmenorrhea (painful menstruation)
2. Amenorrhea (absence of menstruation)
• Primary amenorrhea - when girl has not
menstruated by about age of 18 years.
• Secondary amenorrhea - absence of menstruation
if she has had at least one period.
Disorders of Menstrual cycle
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22. 3. Premenstrual Syndrome (PMS)-Fluctuations in
Mood:
 PMS is a combination of severe physical
and psychological symptoms, such as depression and
irritability, occurring just before menstruation.
 Causes of the Premenstrual Syndrome (PMS):
• Biological factors fluctuations in levels of
hormones
Disorders of Menstrual cycle ..cont..
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23. 4. Abnormal Uterine Bleeding:
 Menorrhagia: Heavy or prolonged uterine bleeding that
occurs at regular intervals. Some sources define further as the
loss of ≥ 80 ml blood per cycle or bleeding > 7 days.
 Metrorrhagia: Irregular menstrual bleeding or bleeding
between periods.
 Polymenorrhea: Frequent menstrual bleeding. Strictly,
menses occur 21 days or less.
 Oligomenorrhea: Menses are > 35 days apart.
..Interventions based on cause of disorder…
Disorders of Menstrual cycle ..cont..
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24. Process of Conception
Process of Conception
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26. Process of Conception
• Conception is when sperm and egg meet and
fertilization occurs.
• Sperm - one of the tiniest cells in the human body.
• Conception occurs in the outer third of the fallopian
tube.
• Zygote - fertilized egg
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28.  Time intercourse so it occurs around time of
ovulation.
 Sperm live inside a woman’s body for up to 5 days.
 Egg is capable of being fertilized for about the first 12
to 24 hours after ovulation.
 Position during and after intercourse is important.
Improving the Chances of Conception
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30.  Presumptive Signs: breast changes, amenorrhea,
nausea, vomiting, fatigue, frequent urination.
 Probable Signs: Positive pregnancy test, physical
changes in the uterus.
 Positive Signs: Ultrasound or X-ray of fetus, fetal
heartbeat, fetal movement
Diagnostic Signs of Pregnancy
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31. Nine months of pregnancy are divided into
three equal periods of three months - called
trimesters
– First trimester - months 1 to 3
– Second trimester - months 4 to 6
– Third trimester - months 7 to 9
Development of the Conceptus
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32.  Placenta - an organ formed on the wall of the
uterus through which the fetus receives oxygen
and nutrients and gets rid of waste products.
 Umbilical cord - the tube that connects the fetus to
the placenta.
 Amniotic fluid - the watery fluid surrounding a
developing fetus in the uterus.
The Embryo and Its Support Systems
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33. Thank you
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