pregnancy and foetal growth

Question 1

how do you determine the gestation of a foetus

Answer 1

• 40 weeks from last menstrual period
• 38 weeks from fertilisation
• estimation via length and ultrasound measurements of foetus

Question 2

common physical signs of pregnancy

Answer 2

• cessation of menstruation
• morning sickness
• increased frequency of urination
• increased size of breasts
• fatigue
• darkening of areolae

Question 3

what are the 2 foetal membranes

Answer 3

aminon

chorion

Question 4

explain the vessels in the umbilical cords

Answer 4

1 umbilical vein = oxygenated

2 umbilical arteries = deoxygenated

Question 5

explain the anatomy of the placental/blood interface

Answer 5

• maternal blood vessels drain into the blood lakes

- chorionic villi with blood vessels into the blood lakes

Question 6

which organs in the foetus does the placenta essentially replace

Answer 6

lungs
kidneys
GIT

Question 7

what is the function of hCG

Answer 7

rescues the corpus lutem –> survives until a stable placenta made

Question 8

function of human placental lactogen

Answer 8

breast development

metabolic effects on mother

Question 9

functions of oestrogen and progesterone during pregnancy

Answer 9

pregnancy maintenance

breast development

Question 10

explain the feedback mechanism for labour

Answer 10

once rhythmic uterine contractions are initiated they are sustained by positive feedback by oxytocin and prostaglandins

Question 11

what are some of the proposed triggers for labour onset

Answer 11

• CRH
• foetus stretching the cervix
• placental role
• oxytocin –> triggers prostaglandin release

Question 12

which hormones cause the development of breast gland tissue during pregnancy

Answer 12

oestrogen
GH
cortisol

Question 13

what change in the breasts occurs in late pregnancy and under what hormone

Answer 13

progesterone stimulates conversion of ducts to secretory epithelium

Question 14

how is lactation inhibited during pregnancy

Answer 14

by prolactin-inhibiting hormone

Question 15

what are the hormonal changes that occur after birth causing lactation

Answer 15

high prolactin and low oestrogen (due to placental removal)

Question 16

how does suckling influence hormones

Answer 16

• inhibits PIH allowing prolactin to stimulate milk production for the next feed
• stimulates oxytocin to trigger myoepithelial cells for milk ejection for this feed
• inhibits GnRH and the ovarian cycle

Question 17

what are the 3 major pregnancy complications

Answer 17

preterm labour
pre-eclampsia
IUGR

Question 18

what is the definition of preterm labour

Answer 18

labour before 37 weeks gestation

Question 19

what proportion of deliveries are preterm

Answer 19

5-8%

Question 20

why is preterm labour bad

Answer 20

because it counts for 80% of perinatal mortality and morbidity

Question 21

what is the eitology of preterm labour

Answer 21

• unknown
• role of infection
• premature rupture of membranes
• multiple pregnancy
• polyhydramnios

Question 22

what is pre-eclampsia

Answer 22

high maternal blood pressure, causing proteinuria and generalised oedema

Question 23

why is pre-eclampsia bad

Answer 23

can lead to eclapsia, placental dysfunction and IUGR

Question 24

pre-eclampsia is common when

Answer 24

first pregnancy

Question 25

what causes pre-eclampsia

Answer 25

dependent on trophoblasts

- unknown

Question 26

what is the treatment of pre-eclampsia

Answer 26

delivery

Question 27

what contributes low birth weight

Answer 27

<2500g

Question 28

what defines small for gestational age

Answer 28

<2SD below population mean

Question 29

what controls foetal growth

Answer 29

genetic factors
hormonal factors
environmental factors

Question 30

which hormones promote foetal growth

Answer 30

IGFs
thyroid hormones
insulin

Question 31

what hormone inhibits foetal growth

Answer 31

corticosteroids

Question 32

what are the major causes foetal growth restriction in Western and third world societies

Answer 32

western - placental insufficiency
third world - maternal undernutrition
(both show decreased nutrient delivery across the placenta)

Question 33

why is IUGR bad

Answer 33

increased risk of developing adult disease

Question 34

what additional growth is independently associated with the development of disease later in life

Answer 34

late accelerated growth as a child

Question 35

what are the critical periods of growth during development that is associated with increased risk of developing adult disease

Answer 35

• lactation/postnatal/infancy
• after weaning/childhood
• after puberty/adolescence

Question 36

what is the sex difference in IUGR babies

Answer 36

male babies more affected

Question 37

what is the association in female babies with IUGR

Answer 37

there physiology has an increased risk of being compromised when pregnant leading to beta cell dysfunction and kidney problems and therefore adverse consequences for foetus