9-1: 10/25: Hormonal Changes In Pregnancy

Front 1

These embryonic cells produce hormones during pregnancy.
IS THIS FC NECESSARY?

Back 1

Cytrotrophoblast and

Syncitiotrophoblast:
Direct contact w/maternal blood in intervillous space; preferentially secreted into mother

Makes protein hormones (hCG)

Front 2

hCG subunits and homology.

Back 2

HCG:
Alpha subunit: homologous to FSH, LH, TSH
Beta subunit: specific to HCG, but similar to LH

Detectable at 6 days post implantation (before missed menses)

Front 3

hCG function

Diagnostic Utility (Syndrome Specific)

Back 3

Critical for maintenance of corpus luteum (PG production to maintain endometrium)

Later stimulates T secretion by fetal testes

Weak thyrotrophic activity

Higher in Trisomy 13/21, and lower in trisomy 18

Front 4

Human Placental Lactogen:
AKA
When is it produced?
Produced by?

Back 4

Human Chorionic Somatomammotropin (HCS)

Produced day 18 of pregnancy (not essential for normal pregnancy!)

Produced by syncytriotrophoblast

Front 5

HPL Function

Back 5

Increases insulin levels (diabetogenic)
Stimulates IGF-1 production, induces insulin resistance
Enhances lipolysis (critical in fasting state)

Front 6

hCG levels vs hPL levels

Back 6

hCG rises very rapidly, peaking at 10 weeks from LMP

hPL begins to rise around 6 weeks, and increases exponentially, peaking at birth

Front 7

Effect of food intake on hPL.

Back 7

Food intake will increase glucose levels and cause a decrease in hPL; thus, decreased lipolysis/FFA's

Note: glucose passes readily from maternal compartment to placental compartment to fetal compartment

Front 8

Effect of fasting state (sleep) on hPL.

Back 8

Inc'd hPL-->inc'd lipolysis and FFA
Ketones increase and readily pass into fetus

Front 9

Describe sources of progesterone production throughout pregnancy.

Back 9

For first 7-10 weeks from LMP, corpus luteum produces PG to maintain endometrium

Marked increase in placental PG from 6 weeks to term

17OH PG rises early (ovarian origin), but returns to baseline by 10 weeks

(only need corpus luteum for first 10 weeks!)

Front 10

Progesterone function.

Back 10

Uterine relaxation

Prepared endometrium for implantation

Breast glandular dev't

Suppresses maternal immune response

Substrate for production of fetal steroids (GC's, MC's)--fetus can't make PG!

Front 11

Describe progesterone synthesis and transfer in the maternal, placental, and fetal compartments.

Back 11

Maternal: LDL Cholesterol and Pregneneolone both enter Placental Compartment

Placental:
LDL-->Pregnelenon-->Progesterone (PG can then go to mom or baby); can't go any further bc lacks 17-alpha hydroxylase CYP17

Fetal:
LDL Cholesterol-->Prenenolone; can't go any further bc lacks 2-beta OH dehydrogenase

Pregnenolone can re-enter placenta

Front 12

Estrogens:
Precursors
Sources

Back 12

Androgen is estrogen precursor

Ovary and extra ovarian sites: E1, E2
Placenta produces E3 (E1 and E2 to a lesser extent)

Front 13

Describe progesterone synthesis and transfer in the maternal, placental, and fetal compartments.

Back 13

Front 14

Estrogen function

Back 14

Physiologic changes of pregnancy
Breast preparation for lactation
Cervical ripening--preparation for labor

Front 15

Placental sulfatase:
Function
Result of Deficiency

Back 15

Enzyme required to produce estrogen in placenta

Deficiency results in failure to have cervical ripening; failure to go into labor (post dates pregnancy)--x-linked recessive dz seen in males, assocd postnatally with ichthyosis (severe cracked skin )