it's very important to know hormonal control of pregnancy.i describe here about it...

1. PRESENTATION ON
HORMONAL CONTROL OF PREGNANCY,
HUMAN AS AN EXAMPLE
Course no: GEB 200
Course title:semimar and oral
Presented by:
Srijon ghosh
Reg. no.:2014431010
Session:2014-15
Dept. of Genetic Engineering and Biotechnology

2. INDEX
 PREGNANCY.
 MATERNAL CHANGES DURING PREGNANCY.
 HORMONAL control OF PREGNANCY.
Role of estrogens, progesterone in Pregnancy.
Human Chorionic Gonadotropin Hormone(hCG)
Corticotropin Hormone.
Oxytocin Hormone.
mechanism of these hormones
 Conclusion.
 Reference.

3. PREGNANCY
 Pregnancy, also known as gravidity or gestation,
is the time during which one or
more offspring develops inside a woman.

4. MATERNAL BODY CHANGES DURING
PREGNANCY.
 During pregnancy the Uterus enlarge considerably.
It increases to about 1kg at full term.
 The Maternal blood volume increases to 30%
during pregnancy.
 The Heart appears to enlarge during pregnancy.
 The Cardiac output also increases.
 The Breast is to estimulate to secrete milk.This is
done by a hormone Prolactine.
 Oxygen consumption is increases during pregnancy
to satisfy the needs of the Fetus.

5. DURATION OF PREGNANCY.
 The Average duration of Human pregnancy is about
280 days(10Menstrual cycle).
 When calculated from the 1day of the last
menstrual cycle.
 266-270 when calculated from the time of
Ovulation.

6. HORMONAL CONTROL OF
PREGNANCY
 During Pregnancy hormones play a significant role
in triggering changes in the Mother and Fetus.
 Hormones maintain the linning of the Uterus and
prevent Menstruation.
 Hormone increases Flexibility of the Pubic
Symphysis.
 Hormone determine the timing of Birth.

7. These are following Hormones which are controlled in
pregnancy:
 1Estrogen Hormone.
 2.Progesterone Hormone.
 3.Relaxin Hormone.
 4.Human Chorionic gonadotropin Hormone.
 5.Corticotropin Hormone.

8. ROLE OF ESTROGEN HORMONE IN
PREGNANCY
 Estrogens play a vital role in Pregnancy.
 1.The oestrogenic group of hormones comprises
three hormones
(a) Estradiol: It is the most active hormone
present in almost all Vertebrates.
(b) Estrone: It is a circulating hormone.
(c) Estriol: It is found in the Urine of Pregnant
women and in the Placenta.

10.  2.Progesterone is a luteal hormone which is synthesized
by Corpus luteum, adrenal cortex, placenta.
 Progesterone is a pregnancy hormone which acts on
genital tissue and induces proper functioning of Breast.
 3.Relaxin is also produced by the corpus luteum which is
causes softening of Epiphysis and facilitates delivery.
 Small quantity of relaxin also occur in the placenta.
ROLE OF PROGESTERONE AND RELAXIN
HORMONE IN PREGNANCY

11. HUMAN CHORIONIC GONADOTROPIN
HORMONE
 The hormone human chorionic gonadotropin (better
known as HCG) is produced during pregnancy.
 It is made by cells that form the placenta, which
nourishes the egg after it has been fertilized and
becomes attached to the uterine wall.
 Levels can first be detected by a blood test about 11
days after conception and about 12 – 14 days after
conception by a urine test.
 In general the hCG levels will double every 72 hours.
 The level will reach its peak in the first 8 – 11 weeks of
pregnancy and then will decline and level off for the
remainder of the pregnancy.

12. FUNCTIONS OF HCG HORMONE
 Human chorionic gonadotropin hormone(hCG) enhances
maternal breast growth by increasing protein synthesis.
 Hcg increases maternal fatty acid for ATP production, leaving
more glucose available for Fetus.
 HCG helps to maintain pregnancy and affects the
development of baby (fetus).
 The amount that hCG increases early in pregnancy can give
information about your pregnancy and the health of your baby.
Soon after delivery, hCG can no longer be found in your blood.


13. CORTICOTROPIN HORMONE-RELEASING
HORMONE
 Corticotropin-releasing hormone (CRH) also
known as corticotropin-releasing factor (CRF)
or corticoliberin is a peptide hormone and neuro
transmitter involved in the stress response. It
belongs to corticotropin- releasing factor family.
 In humans, it is encoded by the CRH gene.
 CRH is secreted by the para ventricular
nucleus (PVN) of the hypothalamus in response to
stress.

14. FUNCTION OF CORTICOTROPIN
HORMONE-RELEASING HORMONE
 CRH is also synthesized by the placenta and
seems to determine the duration of pregnancy.
 In the placenta, CRH is a marker that determines
the length of gestation and the timing of
parturition and delivery.
 CRH may act as a trigger for parturition

15. OXYTOCIN HORMONE
 The hormone oxytocin plays a key role in labour.
 Often called the ‘love hormone’, oxytocin is associated with
feelings of bonding and motherhood.
 This is also true of another hormone released during labour
called prolactin.
 If labour needs to be induced (brought on artificially), oxytocin
or a synthetic oxytocin equivalent is often administered to ‘kick-
start’ the process.
 Oxytocin levels rise at the onset of labour, causing regular
contractions of the womb and abdominal muscles.
 Oxytocin induced contractions become stronger and more
frequent without the influence of progesterone and oestrogen,
which at high levels prevent labour.

16. The menstrual cycle refers to the normal
changes in your ovaries and uterus that make an egg
accessible for fertilization and prepare your uterus for
pregnancy. It typically occurs once every 28 days. If it’s
ovulating normally, an egg, or ovum emerges from one or
other of your ovaries, leaving behind a structure called the
corpus luteum. This structure produces large amounts of
progesterone and estrogen, hormones that help prepare
your uterus for implantation of a fertilized egg.
MECHANISM OF HORMONES IN PREGNANCY

17. MECHANISM OF HORMONES IN PREGNANCY
If the egg is not fertilized, the
corpus luteum degenerates,
causing progesterone and
estrogen levels to drop, and
menstruation to begin.
If the ovum is fertilized, on the
other hand, the corpus luteum
remains intact and continues to
maintain the hormone levels you
need to keep your uterus baby-
friendly. Eventually, the placenta
develops the ability to secrete the
necessary hormones itself, and
the corpus luteum typically
disappears after 3 to 4 months.

18. In addition to progesterone and estrogen, human chorionic
gonadotropin also spikes in early pregnancy(first trimester). The
levels of this hormone double every two days in the first 10 weeks
of pregnancy. Its primary role is to prevent any further
menstruation, and to prepare the placenta - the organ that connects
the fetus to the uterus. The rapid increase in the levels of human
chorionic gonadotropin..these hormones (estrogen and
progesteron ) increases in 2nd trimester,but in this time hCG are
decreased. And in 3rd trimester,all hormones are dropped and
parturation occur.

19. CONCLUSION.
It is concluded that, the whole process of pregnancy
occurs under the influence of hormones. Hormonal
regulation play important role in all these processes.
Imbalance of any one hormone out of all these
hormones, can affect the all these processes.
Hormones are regulated by pitutary gland of
hypothalamus. Releasing time of also important so
that at particular time the hormone level is same as it
required for complete process.

20. REFERENCE:
 Essential of Animal Physiology: By S.C RASTOGI
 Human Physiology: By C.C CHATERJEE.
 Animal Physiology: By P.S VERMA.
 INTERNET SOURCE.