3. AIMS AND OBJECTIVES
Gain knowledge about hormonal cycle.
Understand the terminology of hormonal cycle
Understand the HPO axis.
Gain knowledge about the placental hormones and it function
4. HORMOAL CYCLE
Menstrual is a Latin word: Lunar month of 28 day
Definition: Cyclic physiological changes that take place during
reproductive period in female.
5. Terminology
Menorrhea : A woman’s first menstruation.
Starts typically around 11-12 years
Depends on overall health and diet
Menopause: End of woman’s reproductive phase.
Around 45-50 years
Duration: 28 days (20 to 40 dyas)
7. Change in Hormonal Secretion ( During Menstrual cycle)
1.Proliferative phase (estrogens)
2. Secretory phase (progesterone)
3. Menstrual phase (commences as
hormone production by corpus luteum
declines)
8. Hormonal control of Menstrual cycle
HPO Axis
1.Hypothalamic Hormone – GnRH
2.Anterior Pituitary Hormones – FSH and LH
3.Ovarian Hormones – Estrogen and Progesterone
9. COMPONENTS OF THE AXIS
HYPOTHALAMUS
PULSATILE
GnRH
THE PITUITARY
LH FSH
THE OVARIAN UNIT
ESTRADIOL POSITIVE FB
PROGESTERONE NEGATIVE FB
10. Hypothalamic Hormone
oGnRH is also known as luteinizing hormone
releasing hormone (LHRH)
oIt stimulates secretion of FSH and LH from
anterior pituitary
It’s secretion depends on
1.External factor like psychological events which act on
Hypothelamus via cortex and other brain centers
1.Feedback via Ovarian hormones
11. Role of Hypothalamic
The hypothalamus secrets GnRH in a pulsatile fashion
GnRH activity in first evident at puberty
Follicular phase GnRH pulses occur hourly
Luteal phase GnRH pulses occur hourly
Loss of pulsatility (down regulation pituitary
receptor, secretion of Gonadotrophins.)
Release of GnRH is modulated by negative feedback
by steroids gonadotropins
Release of GnRH is modulated by external neural signals
12. Anterior Pituitary Hormone
FSH and LH
FSH stimulated recruitment and growth of immature
ovarian follicles.
LH triggers Ovulation and sustains corpus luteum.
Depending on their plasma levels, affect may be positive,
negative or both.
Oestrogen, in high concentration (just before Ovulation)
inhibits FSH secretion (negative feedback) and promotes
LH secretion (by Positive feedback)
High levels of gonadal hormones in mid luteal phase inhibit
secretion of both FSH and LH (negative feedback)
Low levels of gonadal hormones (during menstruation phase)
increase secretion of both FSH and LH (positive feedback)
13. Ovarian Hormones
Estrogen and Progesterone
Ovarian follicles secrets estrogen and corpus
luteum secretes progesterone
Estrogen is responsible for growth of follicles
Both hormones act together to produce changes
in uterus, cervix and vagina.
14. The Female Reproductive Hormone
Hypothalamus
GnRH
Pituitary gland
FSH
Ovaries
Ova Estrogen and Progesterone
Hormonal regulation of the female reproductive system
LH
17. CONT...
Fetal, placental & maternal compartments
form an integrated hormonal unit
The feto-placental-maternal (FPM) unit
creates the
Endocrine Environment
that maintains and drives the processes of pregnancy and
pre-natal development.
18.
19. CONT...
ENDOCRINE—hormones secreted internally
HORMONE--Any organic chemical that is secreted by a gland into the circulatory
system and is transported to some target organ. The target may be either peripheral
tissue (such as muscle or other gland) or brain.
20. To understand the FPM one should know:
1. The major hormones involved:
hCGn
Progesterone
Estrogen
Human Chorionic Somatomammotropin (hCS)
(placental lactogen)
2. How the FPM compartments work together
to produce the steroid hormones
3. The transfer of hormones between
the FPM compartments.
21.
22. Human Chorionic Gonadotropin
(hCG)
PREGNANCY HORMONE---glycoprotein
Half life –24hrsof hCG
Levels peak at 60-70 days then remain at a low plateau for the
rest of pregnancy.
Placental GnRH have control of hCG.
FUNCTIONS:
1. RESCUE &MAINTENANCE of function of corpus luteum.
23. CONT...
Prevents degeneration of corpus luteum
Stimulates corpus luteum to secrete E + P
which, in turn, stimulate continual growth of
endometrium.
2.hCG stimulates leydig cells of male fetus to
produce testosterone in conjunction with
fetal pituitary gonadotrophins.Thus indirectly
involed in development of external genitalia.
3. Suppresses maternal immune function
& reduces possibility of fetus
immunorejection
24. Human Chorionic Somammotropin
(hCS)
or Placental Lactogen
Structure similar to growth hormone
Produced by the placenta
Levels throughout pregnancy
Large amounts in maternal blood but
DO NOT reach the fetus
25. Human Chorionic Somammotropin
(hCS)
or Placental Lactogen
Biological effects are reverse of those of insulin
utilization of lipids ; make glucose more readily
available to fetus, and for milk production.
hCS levels proportionate to placental size
hCS levels placental insuffiency
26. Estrogen (E)
FORMS-estriol,estradiol &estrone .
Estriol most important .
Levels increase throughout pregnancy
90% produced by placenta.(syncytiotrophoblast)
Placental production is transferred to both maternal and fetal compartments
27. CONT...
Two of the principle effects of placental
estrogens are:
Stimulate growth of the myometrium and
antagonize the myometrial-suppressing
activity of progesterone. In many species, the
high levels of estrogen in late gestation
induces myometrial oxytocin receptors,
thereby preparing the uterus for parturition.
Stimulate mammary gland development.
Estrogens are one in a battery of hormones
necessary for both ductal and alveolar growth
in the mammary gland.
29. CONT...
Progestins, including progesterone,
have two major roles during pregnancy:
Support of the endometrium to provide an
environment conducive to fetal survival. If the
endometrium is deprived of progestins, the
pregnancy will inevitably be terminated.
Suppression of contractility in uterine
smooth muscle, which, if unchecked, would
clearly be a disaster. This is often called the
"progesterone block" on the myometrium.
Toward the end of gestation, this myometrial-
quieting effect is antagonized by rising levels
of estrogens, thereby facilitating parturition.
30. CONT...
Progesterone and other progestins also potently inhibit secretion of the pituitary
gonadotropins luteinizing hormone and follicle stimulating hormone. This effect almost
always prevents ovulation from occuring during pregnancy
31. Men Reproductive Hormone
Men have about 10 times more testosterone than women,
so their hormone cycle is usually all about how their
testosterone affects them.
A man’s body does make estrogen and progesterone
like a woman’s body, but in much smaller amounts.
32. Morning testosterone in highest : Once he shakes off the log of sleep,
high testosterone make him more
energetic, take tire, aggressive,
focused and competitive.
So it is the best time for him for : Compete in a contest
Work on a project solo
Figure out the best driving route.
33. Afternoon: Testosterone is in the middle of its cycle :
He’s a tad mellower than his morning self, but isn’t going on empty
just yet. As a result, he’s still upbeat, driven and focused but not as
easily ticked off. He’s more open to working with otherrather than
Going solo.
Best time for him to: Work as part of a team, pitch clients or
customers, brainstorm ideas, go on a date.
34. Evening Testosterone is lowest:
With testosterone bottoming out, he tends to be more passive,
Agreeable and low-key, making this a good time to ask him for
A favor or other request. Since he’s more likely to grant it.
He may feel tired or fuzzy – especially before he had a chance
To recharge after work or eat dinner.
At this point, his libido hits its lowest point. For some
Men this low point is still enough to make them capable of
enjoying passionate sex; other men may feel too tired for intimacy
Or have difficulty maintaining an erection.
35. Best time for him to : do activities that rejuvenate his energy
if he wants a pick-me-up (such as playing
an instrument or exercising), enjoy reluxing activities in keeping
With his current low energy level (such as reading or watching a
documentary), cuddle with his partner.
38. CONCLUSION
this cycle is the regular natural change that occurs in the female reproductive system
that makes pregnancy possible.
this cycle is required for the production of ovocytes, and for the preparation of the
uterus for pregnancy.
39. BIBLIOGRAPHY
Billings ,E.L.and westmore,A (2011) the billings method (9th edition ),Melbourne
,Australia;Anne o'Donovan publishing.
2.brown, J.B(2011)tyoes of ovarian activity in women and their significance; the
continuum human reproduction update,17(2) 141-158
3.odeblad ,E(2010) contributions of cervical mucus and vestibular factors to peak
sensation .37(2) 2-8
4.odeblad ,e.(2009)some additional aspects of the physiology of the mucus symptom
,36(3) 2-7
5.http;//humupd.oxfordjournals.org/content /17/2/141.full pdf+html
