Pregnancy hormones

Question 1

Where is beta HCG produced?

Answer 1

The placenta (syncytiotrophoblast)

Question 2

What hormones are similar in structure to betaHCG?

Answer 2

The alpha subunit in HCG is similar to LH/FSH/TSH (not the beta subunit)

Question 3

What is the main function of HCG?

Answer 3

To maintain the corpus luteum in the first trimester to secrete progesterone to maintain the lining of the uterus (thickened and vascular)

Question 4

When do HCG levels peak in pregnancy

Answer 4

At the end of the first trimester - they gradually fall after this point

Question 5

Where are oestrogen and progesterone produced during pregnancy.

Answer 5

In the first trimester oestrogen and progesterone are mainly produced in the ovary, in the second and third trimesters the placenta takes over

Question 6

Which hormone has a similar structure to human placental lactogen?

Answer 6

Human growth hormone

Question 7

When does HPL get produced in pregnancy?

Answer 7

From the 6th week onwards

Question 8

Oestrogen impact on breast tissue in pregnancy

Answer 8

Develops the ductal system of the breast

Question 9

Progesterone impact on breast tissue in pregnancy

Answer 9

Develops of breast lobules

Question 10

What is the role of oestrogen during pregnancy?

Answer 10

Inhibition of LH and FSH
Stimulate growth of the fetus
Stimulate maternal tissue growth -uterus and mammary glands and ducts

Question 11

What hormone causes involution of the uterus after delivery?

Answer 11

Oxytocin

Question 12

What hormones are released by the corpus luteum?

Answer 12

Progesterone and relaxin

Question 13

What progesterone is only produced by the corpus luteum?

Answer 13

17-hydroxyprogesterone is not produced by the placenta

Question 14

What is the function of the corpus luteum?

Answer 14

To secrete hormones to support pregnancy - progesterone (decidulisation and maintenance of the endometrium) and relaxin for softening the pubic symphysis - it secretes these hormones in response to HCG which is released by the syncytiotrophoblasts of the implanting embryo

Question 15

What happens to the corpus luteum if the egg is not fetilised?

Answer 15

It degenerates within 10 days to the corpus albicans (fibrous scar)

Question 16

Where is oestradiol produced?

Answer 16

ovarian follicles, corpus luteum, placenta, liver, adrenal glands, breast, adipocytes

Question 17

What is estradiol metabolised to?

Answer 17

Metabolised in the liver to estrone E1 and estriol E3

Question 18

What form is estradiol excreted by the kidney?

Answer 18

estriol glucuronide

Question 19

What will LH and FSH levels be in pregnancy?

Answer 19

Low or none (suppressed by progesterone and oestrogen)

Question 20

What happens to glucocorticoid secretion during pregnancy?

Answer 20

Increases in the 2nd trimester

Question 21

When is relaxin production at it’s highest?

Answer 21

In the first trimester (secreted by the corpus luteum)

Question 22

When does 17-hydroxyprogesterone levels peak?

Answer 22

Produced by the corpus luteum only - these peak at week 5

Question 23

How do thyroid levels change in pregnancy?

Answer 23

Free T3 and T4 remains unchanged, total T3 and T4 increased initially then plateaus at week 10-15 (after the 1st trimester)

Question 24

How do insulin levels change during pregnancy?

Answer 24

Increase in the 2nd trimester, insulin resistance occurs