Endocrinology of Pregnancy

Question 1

What does Kisspeptin do?

Answer 1

Profoundly stimulates GnRH and initiate puberty

Question 2

When is Kisspeptin usually seen to spike during menstrual period?

Answer 2

Right before ovulation causing LH surge

Question 3

What is seen in a Basal Body Temperature chart?

Answer 3

Resting core temperature is measured every morning, mid-cycle there is first a decrease in BBT due to LH surge followed by an elevation in BBT showing ovulation, a dip past ovulation shows implantation and then a large increase to BBT due to progesterone

Question 4

What is Resting Core Temperature?

Answer 4

Temperature taken as you wake up in the morning before energy is being consumed

Question 5

Why does progesterone cause a 1 degree F increase after pregnancy?

Answer 5

Because progesterone is thermogenic

Question 6

What time range must the ovum be fertilized around ovulation?

Answer 6

Within 24-48 hours

48 hours around ovulation

Question 7

Where does fertilization normally occur?

Answer 7

In the ampulla

Question 8

What is the first source of hCG?

Answer 8

Corpus luteum

Question 9

What does hCG have similar functions as?

Answer 9

FSH
LH
TSH

Question 10

hCG titer for “not pregnant”?

Answer 10

Below 5 mIU/mL

Question 11

hCG titer for “pregnant”?

Answer 11

Greater than 25 mIU/mL

Question 12

How long does 1,200 mIU/mL of hCG in early pregnancy take to double?

Answer 12

48-72 hours

Question 13

How long does between 1,200-6,000 mIU/mL of hCG take to double?

Answer 13

72-96 hours

Question 14

How long does it take for levels of hCG above 6,000 mIU/mL take to double?

Answer 14

Over four days

Question 15

What cells create hCG?

Answer 15

Syncytiotrophoblasts

Question 16

What releases relaxin?

Answer 16

Corpus luteum and later the placenta

Question 17

What does relaxin do?

Answer 17

Promotes decidual angiogenesis of the endometrium

Question 18

What are the two layers the placental epithelial cells form in the uterus?

Answer 18

Cytotrophoblasts

Synctiotrophoblasts

Question 19

What anchors the placenta to the endometrium?

Answer 19

Columns of invading cytotrophoblasts

Question 20

What forms Synctiotrophoblasts?

Answer 20

Fusion of cytotrophoblasts

Question 21

What do Synctiotrophoblasts do?

Answer 21

Are in direct contact with maternal circulation and is the major source of steroid hormone production

Question 22

What is a marker for corpus luteum and why?

Answer 22

17-hydroxyprogesterone because the placenta lacks 17alpha-hydroxylase

Question 23

What effects does hCG have?

Answer 23

Stimulates secretion of P4 from corpus luteum
Stimulates Leydig cells of male fetus to produce testosterone
Immunosuppressive activity (stops mom from rejecting baby as a graft)

Question 24

How much does progesterone increase in pregnancy?

Answer 24

100x increase in concentration

Question 25

Roles of progesterone:

Answer 25

Inhibits T cell mediated allograft rejection Maintains uterine quiescence Proliferation of breast lobular-alveolar structures Suppression of milk protein synthesis during pregnancy

Question 26

What are the four estrogen types?

Answer 26

Estrone (E1) Estradiol (E2) Estriol (E3) Estetrol (E4)

Question 27

Where are the estrogens primarily made?

Answer 27

Ovaries (largest) Placenta (moderate amount) Liver, adrenals and breasts (not as much)

Question 28

Where are most of the placental estrogens derived from?

Answer 28

Fetal androgens mostly DHEAS

Question 29

What is estrogens effect on clotting?

Answer 29

Stimulates fibrinogen

Question 30

What does estrogen cause in the myometrium?

Answer 30

Hypertrophy Hyperplasia Increased vascularity and blood flow to uterus

Question 31

Role of estrogen, progesterone, oxytocin and prolactin in lactation?

Answer 31

Estrogen: promotes development of ductal breast tissue Progesterone: proliferative factor for formation of breast lobular-alveolar structures Oxytocin: acts on muscle elements to cause contraction of ductal system Prolactin: induces secretion of milk

Question 32

What does the placenta produce to negate uterine contractions?

Answer 32

Oxytocinase: an enzyme that negates effects of OT on contractions

Question 33

What markers are used to screen for Down syndrome?

Answer 33

Alpha-fetoprotein (AFP) hCG Inhibin-A Unconjugated Estriol concentrations

Question 34

What will the levels of each of the markers in Down syndrome be?

Answer 34

AFP: low hCG: high Inhibin-A: high Estriol: low

Question 35

What is the role of CRH in early and late pregnancy?

Answer 35

Early: low levels; increases DHEA; inhibit contractions by increasing cAMP in myometrium Late: high levels; activate prostaglandins in uteroplacental tissues to cause contractions

Question 36

What allows prolactin to act on the posterior pituitary to secrete oxytocin in a pulsatile fashion?

Answer 36

Progesterone withdrawal

Question 37

What produced relaxin and what does it do?

Answer 37

Corpus luteum and placenta Decidual angiogenesis Soften and widens pubic symphysis and SI joints Inhibit uterine contractions

Question 38

Progesterone affect on GI tract?

Answer 38

Increased secretions Relaxation of SM Decreased gastric emptying Lowers esophageal muscle tone

Question 39

What occurs to osmolarity in a pregnant women?

Answer 39

Decreased plasma osmolarity due to marked water retention

Question 40

Why does edema occur in pregnancy?

Answer 40

Increased blood volume causes increased BP and decreased oncotic pressure due to decreased osmolarity

Question 41

What effect does progesterone have on chemoreceptors?

Answer 41

Sensitizes them to CO2 causing as increase in ventilation and decreases arterial pCO2

Question 42

What does a fall in maternal pCO2 cause?

Answer 42

More efficient transfer of CO2 from the fetus to the mothers blood

Question 43

What accounts for the darkening or dermatologic adaptations of pregnancy?

Answer 43

Increased MSH (melanocyte stimulating hormone)

Question 44

What occurs to bone metabolism in pregnant patients?

Answer 44

Increased parathyroid activity Estrogens inhibit bone resorption as do progestins Calcitonin levels slightly increase to counter PTH effect

Question 45

Effect of pregnancy on biliary system?

Answer 45

Estrogen inhibits bile transport | Gallbladder contraction decreased by progesterone inhibiting CCK

Question 46

What occurs to HR, CO, BP in pregnancy?

Answer 46

HR increase CO increase BP decrease

Question 47

In first half of pregnancy what causes increased CO?

Answer 47

Increased SV

Question 48

In latter half of pregnancy what causes increased CO?

Answer 48

Increased HR