1. Presented by,
Pooja Rajpurohit
MSC II ZOOLOGY.
Supervised by,
Prof Akshay Shinde Sir
HORMONAL
REGULATION
IN
PREGNANCY

3. Hormones Controlled during Pregnancy:-
1) Estrogen hormone
2) Progesterone hormone
3) Relaxin hormone
4) HCS hormone
5) Corticotropin hormone

4. INTRODUCTION
•During Pregnancy hormones play a
significant role in triggering changes
in Mother and fetus.
• HORMONES;
~ Maintain the lining of the Uterus and
prevent Menstruation.
~ Prepare Mammary glands for
Lactation.
~ Increase flexibility of pubic
symphysis.
~ Affects mother’s metabolic rate and
Enhance fetal growth.
~ Determine timing of birth.

5. Hormonal regulation of Pregnancy
Week 1:-
• During the first week after
fertilization, the ovarian corpus
luteum continues to secrete
hormones that are essential to
maintain the normal female
reproductive cycle.
• After blastocyst embeds in the
endometrium it secretes
Human Chorionic Gonadotropin
(HCG).

6. *HCG prevents the ovarian corpus
luteum from degenerating so that
it can continue to secrete estrogen
and progesterone which act to
maintain the nourishing secretions
of the endometrial lining.
*Because of maintainance of level
of progesterone and estrogen,
menstruation does not occur.
*HCG is detectable in a woman’s
blood and urine about 8 days after
fertilization.

7. Hormonal regulation of Pregnancy,
Week 2-16:-
• During first few months of
pregnancy, estrogen and
progesterone are secreted
primarily by the corpus luteum.
• These hormones act to maintain
nutritional support for embryo and
fetus.
• HCG production increases, peaking
at 8 weeks.
• HCG triggers the corpus luteum to
produce ever increasing levels of
estrogen and progesterone.

8. By 9th week , the placenta is
the primary source of
estrogen and progesterone.
• After 4th month, levels of
HCG decrease significantly
and stay at a low level.
• Following the 4th month,
rising levels of placental
estrogen and progesterone
are sufficient to maintain
pregnancy.

9. Hormonal regulation of
Pregnancy –
Week 17-38
• The placenta is the
primary source of
pregnancy hormones.
• These hormones include;
- Estrogen
- Progesterone
- Relaxin
- Human Chorionic
Somatomammotropin
- Corticotropin – releasing
hormone.

10. • Estrogen increase uterine blood
flow , maintaining the
endometrium during Pregnanc.
• High levels of estrogen and
progesterone inhibit the synthesis
of milk.
• Progesterone inhibits contraction
of uterus to prevent premature
birth.
• Relaxin inhibits contraction of
uterus, also increases flexibility of
pubic symphysis to aid in birth

11. Human Chorionic
Sommatomammotropin (HCS)
• hCS enhances maternal breast
growth by increasing protein
synthesis.
• hCS helps prepare Mammary
glands for Lactation.
* hCS increases maternal fatty
acid use for ATP production
leaving more glucose available
for fetus.

12. Corticotropin Releasing Hormone.
CRH stimulates the fetal
anterior pituitary glands to
secrete ACTH.
ACTH stimulates fetal
cortisol , which triggers
fetal Lung maturation and
production.

13. CRH Level increases greatly
towards the end of
Pregnancy , and stimulates
fetus and placenta to
produce more and more
estrogen.
Increased level of
estrogen act as timer for
birth and preparation for
Lactation.

14. CONCLUSION
It is concluded that the whole
process of pregnancy occurs under
the influence of hormone.
Hormonal regulation play an
important role in all these processes.
Imbalance of any one hormone out
of these hormones, can affect all
these processes.
Hormones are regulated by Pituitary
gland of hypothalamus.

15. THANKS FOR YOU
ATTENTION !!!
Rajpurohit Pooja,
MSC II ZOOLOGY