NURSING

6. Follicular maturation takes place during the first half of the
cycle.
The hormones essential for follicular maturation are mainly
FSH and a small proportion of LH. For continued FSH activity,
estrogen is necessary.
•OVULATION:
Under the influence of FSH, about 20 Graafian follicles develop
synchronously and only one of them will be able to ovulate.

7. CHANGES WITHIN THE FOLLICLE AFTER OVULATION:
• The avascular Graafian follicle becomes vascularized
and the granulosa cells become luteinized.
• The morphologically altered Graafianfollicle is now
changed into corpus luteum.
 The corpus luteum secretes hormones:-
• progesterone,
• 17Alfa-hydroxyprogesterone
• estradiol
• androstenedione (theca cells)

9. •Function of corpus luteum is essential to maintain
the early pregnancy
• Corpus luteum secretes about40 mg of
progesterone a day.
• After implantation, human chorionic
gonadotropin (hCG) and possibly human
placental lactogen (hPL), secreted by the
syncytiotrophoblast cells maintain the growth
and function of the corpus luteum.

10. PLACENTAL ENDOCRINOLOGY
•At 6–8 weeks, there is transfer of functions of
corpus luteum to the placenta (luteal-placental shift)
•which acts temporarily as a new endocrine organ or
power house of hormone production.

13. HORMONES OF PLACENTA
•Placenta produces a variety of
hormones of which :-
1. protein
2. steroid hormones

15. Early pregnancy factor (EPF)
Growth factors:
RELAXIN
Pregnancy-associated plasma protein—A
HUMAN CHORIONIC GONADOTROPIN (hCG)
HUMAN PLACENTAL LACTOGEN (hPL)
PREGNANCY-SPECIFIC beta-1 GLYCOPROTEIN

16. HUMAN CHORIONIC GONADOTROPIN (hCG):
•hCG is a glycoprotein.
•Its molecular weight is 36,000–40,000 daltons.
• It consists of a hormone nonspecific alfa (92 amino acids)
and a hormone specific beta (145amino acids) subunit.
•Placental GnRH may have a control on hCG formation

17. Functions:
(1) It acts as a stimulus for the secretion of progesterone by
the corpus luteum of pregnancy. Rescue and maintenance
of corpus luteum till 6 weeks of pregnancy.
(2) hCG stimulates Leydig cells of the male fetus to produce
testosterone. It is indirectly involved in the development of
male external genitalia.
(3) It has got immunosuppressive activity, which may inhibit
the maternal processes of immunorejection of the fetus as a
homograft.
(4) Stimulates both adrenal and placental steroidogenesis.

18. Level of hCG at different periods
of pregnancy:
•hCG is produced by thesyncytiotrophoblast of the placenta
and secreted into the blood of both mother and fetus.
•The plasma half-life of hCG is about36 hours
•it can be detected in the maternal serum or urine as early
as 8–9 days postfertilization.

19. •hCG disappears from the circulation within 2 weeks
following delivery
•The blood and urine values reach maximum levels ranging
from 100 IU/mLto 200 IU/mL between 60 and 70 days of
pregnancy.

20. High levels of hCG in—
(a)multiple pregnancy,
(b) hydatidiform mole or choriocarcinoma
(c) trisomy 21 fetus (Down’s syndrome).
lower levels:-
ectopic pregnancies
spontaneous abortion.

21. HUMAN PLACENTAL LACTOGEN (hPL):
•This is also known as human chorionic somatomammotropin(hCS).
• The hormone is synthesized by the syncytiotrophoblast of
the placenta.
•hPL in maternal serum is first detected during the 3rd
week of gestation.
•The level rises progressively from 5 ug/mL to 25 ug/mL until
about 36 weeks of gestation.
•The plasma concentration of hPL is proportional to placental mass.

22. Functions:
• hPL antagonizes insulin action. High level of maternal
insulin helps protein synthesis.
•hPL causes maternal lipolysis and promotes transfer of
glucose and amino acids to the fetus.
•It promotes growth and differentiation of breasts for
lactation

23. PREGNANCY-SPECIFIC beta-1 GLYCOPROTEIN :
It is produced by the trophoblast cells.
It can be detected in the maternal serum 18–20 days
after ovulation.
Functions:
PS beta-1G is a potent immunosuppressor of lymphocyte
proliferation and prevents rejection of the conceptus.

24. Early pregnancy factor (EPF)
It Is produced by the activated platelets and other
maternal tissues.
It is detectable in the circulation 6 – 24 hours after
conception.
Functions:
EPF is immunosuppressant and prevents rejection of the
conceptus.

25. Growth factors:
Inhibin, activin, insulin-like growth factor (IGF-1 and 2),
transforming growth factor beta (TGF- beta ) and
epidermal growth factor (EGF) are produced by the
syncytiotrophoblast cells.
Functions:
They have varied functions including immunosuppressive,
paracrine and steroidogenic.

26. Pregnancy-associated plasma protein—A (PAPP-A)
it is secreted by the syncytiotrophoblast.
Functions:
It acts as an immunosuppressant in pregnancy.

27. RELAXIN:
•It is a peptide hormone structurally related
to insulin.
• The main source of production is the corpus
luteum of the ovary but part of it may be also
produced by the placenta and decidua.
• the relaxin relaxes myometrium, the
symphysis and sacroiliac joints during
pregnancy.

28. STEROIDAL HORMONES
ESTROGEN:
site of its production is in the syncytiotrophoblast.
Estriol
It is first detectable at 9 weeks (0.05 ng/mL) and increases
gradually to about 30 ng/mL at term.

30. PROGESTERONE:
Before 6 weeks of pregnancy, the corpus luteum secretes 17-alfa
hydroxyprogesterone Following the development of trophoblast,
progesterone is synthesized and secreted in increasing amount from the
placenta.
The daily production rate of progesterone in late normal pregnancy is
about 250 mg.
Low progesterone levels are observed in ectopic pregnancy
and in abortion.
High values are observed in hydatidiform mole, Rh-
isoimmunization.
After delivery, the plasma progesterone decreases rapidly
and is not detectable after 24 hours.

31. • Together they play an important role in the maintenance of
pregnancy.
• Development and hypertrophy of the breasts during pregnancy
•Estrogens sensitizes the myometrium to oxytocin and
prostaglandins
•Progesterone along with hCG and decidual cortisol inhibits T-
lymphocyte mediated tissue rejection and protects the conceptus
•Together they cause inhibition of cyclic fluctuating activity of
gonadotropin–
Functions of the steroid hormones (estrogen and
progesterone):

32. DIAGNOSTIC VALUE OF PLACENTAL
HORMONES:-
(a)Diagnosis of pregnancy—Presence of hCG in the plasma
can be detected by radioimmunoassay and in urine either
by biological or immunological tests.
Radioimmunoassay can detect minute quantity of plasma
hCG beta subunit soon after the implantation of blastocyst
but biological and immunological tests become positive after
the missed period.

33. CHANGES OF ENDOCRINE GLANDS DURING
PREGNANCY
Pituitary, thyroid, adrenal cortex,
parathyroid and pancreas show
distinct physiological changes during
pregnancy leading to increase in
output of respective hormones.

42. PANCREAS
PHYSIOLOGICAL CHANGES IN PREGNANCY: During pregnancy
there is hypertrophy and hyperplasia of the cells of islets of
Langerhans in maternal pancreas.
In pregnancy, there is hyperinsulinemia particularly
during third trimester
Several antinsulin factors (hPL) and other factors (CRP, IL-6,
TNF- and leptin) decrease insulin sensitivity and increase
insulin resistance. Maternal blood glucose level is increased
in the second half of pregnancy. This helps increased
transfer of glucose from the mother to the fetus through the
placenta

43. HORMONAL INFLUENCES NECESSARY
FOR MAINTENANCE OF LACTATION
The endocrine control of lactation can be divided into following stages:
(a) Preparation of breast (mammogenesis),
(b) synthesis and secretion of milk by breast alveoli
(lactogenesis)
(c) ejection of milk (galactokinesis)
(d) maintenance of lactation (galactopoiesis)

45. • Conclusions:
• Endocrinology in relation to reproduction includes the
knowledge of:
• Hormones essential for the maturation of the Graa! an
follicles, ovulation and maintenance of corpus luteum
after fertilization.
• Following conception, transfer of function of pituitary-
ovarian axis to placenta, which acts temporarily as a
new powerhouse or endocrine organ.
• Physiological alteration of various endocrine glands
namely, the pituitary, thyroid, parathyroid,adrenals and
pancreas during pregnancy.

46. •Bibliography
• DC Dutta’s Textbook of Obstetrics,7th edition,pageno.88-95
• Internet source :
www.slideshare/ Endocrinology in relation to reproduction.com
www.google/Endocrinology in relation to reproduction/com