Pregnancy

Question 1

What are the 7 basic principles of pregnancy

Answer 1

Semen formation and voyage

Capacitation

Fertilisation

Implantation

Hormonal changes of pregnancy

Partruition (labour)

Lactation

Question 2

What happens to the fluid of semen as it levels the seminiferous tubules

Answer 2

Tubular fluid reabsorption which increases the concentration - induced by oestrogen

Nutrients and glycoprotein secretion into epididymal fluid induced by androgens

Question 3

How much spermatozoa per ejaculate

Answer 3

15-120 million/ml

Seminal fluid 2-5ml

Question 4

What does the semen contain

Answer 4

Lecuocytes

HIV, Hep B

Sperm

Seminal fluid

Question 5

What other stuff is located is semen analysis reports

Answer 5

Motility - just go around in circles

Question 6

Where does seminal fluid come from

Answer 6

Epididymis/testis

Seminal vesicles

Prostate

Bulbourethral galnds

Question 7

How does the capacitation of sperm happen

Answer 7

Loss of glycoprotein coat

Change in surface membrane characteristics

Development of whiplash movements of tail

Takes place in ionic and proteolytic environment of fallopian tube, oestrogen dependent, Ca dependent

Question 8

What happens in the acrosome reaction

Answer 8

Binds to sperm receptor ZP3

Ca influx into sperm stimulated by progesterone

Release of hyaluronidase and proteolytic enzymes from acrosome

Sperm penetrate zona pellucida

Question 9

What happens during fertilisation

Answer 9

Triggers cortical reaction

Cortical granules release molecules which degrade zona pellucida

Prevents further sperm binding as no more receptors

Question 10

What happens during the development of conceptus

Answer 10

Divide as it moves down fallopian tube to uterus (3-4days)

Receives nutrients from uterine secretions

Can last for 9-10days

Question 11

Diagram of development of conceptus

Answer 11

Question 12

What are the different phases of implantation

Answer 12

Attachment phase - outer trophoblast cells contact uterine surface

Decidualisation phase - changes in underlying uterine stromal tissue

Requires progesterone domination in the presence of oestrogen

Question 13

What molecules are involved in the process of attachmentz

Answer 13

Leukaemia inhibitory factors stimulates adhesion of blastocyst to endometrial cells

Interleukin-11 is released into uterine fluid

Question 14

What are endometrial changes due to progesterone

Answer 14

Grandular eptihelial secretion

Growth of capilaries

Increase vascular permeability

Glycogen accumlation in stromal cell cytoplasm

Factors involved: IL11, histamine, prostaglandins and TGF B

Question 15

What hormone is only present in pregnancy

Answer 15

hCG made by the placenta

Question 16

Hormone changes and effects graph

Answer 16

Question 17

What are the functions of hCG during pregnancy

Answer 17

hCG binds to LH receptors of corpus luteum

Question 18

Where are the progesterone and oestrogen production during pregnancy

Answer 18

Corpus luteum stimulated by hCG produced by trophoblasts

Inhibites LH and FSH

Develop fetoplacental unit

Placenta starts to take over from day 40

Oestrogen comes from androgens, progesterone comes from pregnenolone

Question 19

What are the physiological changes in maternal hormones

Answer 19

Increase in:

ACTH

Adrenal steroids

Prolactin

IGF1

Iodothyronines

PTH related peptides

Decrease in:

Gonadotrophins

Pituitary GH - placenta produces GH

TSH - hCG has TSH like actions

Question 20

What does oxytocin do during partruition

Answer 20

Stimualtes uterine contraction alongside o and p

Cervical dilation

Milk ejection

Question 21

What is the endocrine control of lactation

Answer 21

Suckling stimulus

Pituitary release oxytocin and prolactin