Endocrinology of Pregnancy

Question 1

What induces tubular fluid reabsorption?

Answer 1

Oestrogen

Question 2

What induces the nutrients (eg fructose) & glycoprotein secretion into epididymal fluid?

Answer 2

Androgens

Question 3

How far does the spermatozoa travel?

Answer 3

Travels 100,000 x its length from Testis to Fallopian tube

Question 4

What does semen contain

Answer 4

Spermatozoa- 15-120 million/ml
Seminal fluid - 2-5ml
Leucocytes
(potentially viruses e.g. hepatitis B, HIV)

Question 5

Where is seminal fluid from?

Answer 5

Epididymis/tests

Mainly fron the accessory sex glands

Question 6

What are the 3 accessory sex glands

Answer 6

Seminal vesicles
Prostate
Bulbourethral glands

Question 7

What does sperm do after ejaculation that makes it ready for fertilisation

Answer 7

Capacitation:

1. Loss of glycoprotein ‘coat’
2. Change in surface membrane characteristics
3. Develop whiplash movements of tail

Question 8

Where does capacitation take place?

Answer 8

ionic & proteolytic environment of the Fallopian tube

Question 9

What is capacitation dependent on

Answer 9

Oestrogen and Ca2+

Question 10

What is the acrosome reaction?

Answer 10

Sperm binds to ZP3 (sperm receptor) - G protein mediated response and in the presence of progesterone, Ca2+ influxes into the sperm. Hyaluronidase and proteolytic enzymes are then released (from acrosome). The spermatozoon then penetrates the zona pellucida

Question 11

Where does fertilisation occur

Answer 11

In the fallopian tube

Question 12

What triggers the cortical reaction

Answer 12

Fertilisation

Question 13

What happens in the development of conceptus?

Answer 13

Continued division down the fallopian tube into the uterus. Receieves nutrients from uterine secretions

Question 14

What is hCG

Answer 14

A hormone that is released to maintain progesterone secretion until the placenta takes over

Question 15

What is the attachment phase of implantation?

Answer 15

outer trophoblast cells contact uterine surface epithelium

Question 16

What is the decidualisation phase of implantation

Answer 16

changes in underlying uterine stromal tissue (within a few hours)

Question 17

What does the decidualisation phase of implantation require

Answer 17

progesterone domination in the presence of oestrogen

Question 18

What does the leukaemia inhibitory factor do in the process of attachment

Answer 18

from endometrial secretory glands (& blastocyst?) stimulates adhesion of blastocyst to endometrial cells

Question 19

Where is interleukin 11 made and what is it involved in

Answer 19

also from endometrial cells is released into uterine fluid, and may be involved in the process of attachment

Question 20

What are endometrial changes due to progesterone

Answer 20

Glandular epithelial secretion
Glycogen accumulation in stromal cell cytoplasm
Growth of capillaries
Increased vascular permeability (→oedema)

Question 21

What are factors involved in endometrial changes

Answer 21

Interleukin-11 (IL11), histamine, certain prostaglandins & TGFb (TGFb promotes angiogenesis)

Question 22

Can you recreate the graph for hormone changes of hCG, human placental lactogen, oestrogens and progesterone during pregnancy

Answer 22

Check notes

Endocrinology of pregnancy slide 24

Question 23

Where is progesterone and oestrogen produced in the first 40 days and what is it essential in

Answer 23

Produced in corpus luteum and essential for developing fetoplacental unit and onhibits maternal LH & FSH (-ve feedback)

Question 24

What stimulatethe progesterone and oestrogen produced in the first 40 days

Answer 24

stimulated by hCG (produced by trophoblasts) which acts on LH receptors

Question 25

Where is progesterone and oestrogen produced after the first 40 days

Answer 25

Placenta starts taking over

Question 26

What hormones increase in pregnancy in a woman (7)

Answer 26

ACTH
Adrenal steroids
Prolactin
IGF1 (stimulated by placental GH-variant)
Iodothyronines
PTH related peptides

Question 27

What hormones decrease in pregnancy in a woman (3)

Answer 27

Gonadotrophins
Pituitary GH
TSH

Question 28

What to check in a pregnant woman if are worried about a prolactinoma

Answer 28

Visual field

Question 29

What does oxytocin do in partruition

Answer 29

Uterine contraction
Cervical dilation
Milk ejection

Question 30

What are the 3 main hormones involved in partruition

Answer 30

Oestrogen
Cortisol
Oxytocin

Question 31

How is cortisol made in the fetus

Answer 31

Fetal hypothalamus -> CRH -> Fetal adenohypophysis -> Corticotrophin -> Fetal adrenals -> cortisol

Question 32

What hormone favours milk ejection and which does milk synthesis

Answer 32

Milk ejection: oxytocin

Milk synthesis: prolactin

Question 33

How to treat a patient with a high prolactin

Answer 33

Give Kisspeptin

Question 34

How does prolactin cause an increase in milk synthesis

Answer 34

Prolactin acts directly on Kiss1-expressing neurons and induces suppression of Kiss1 mRNA expression and kisspeptin secretion, leading to a lower activation of GnRH and gonadotropins secretion

Question 35

What is the cortical reaction

Answer 35

Cortical granules release molecules which degrade Zona Pellucida. Therefore prevents further sperm binding as no receptors and turns from haploid chromosome to diploid

Question 36

What happens in fertilisation of the ovum

Answer 36

Acrosome reaction
Cortical reaction
Expulsion of the second polar body
Immediate zona reaction (degradation of the ZP3 coat) to prevent further binding
And once zygote is established, the zygote starts dividing