8.2 Maternal problems in pregnancy (2)

Question 1

what is gestational diabetes?

Answer 1

carbohydrate intolerance first recognised in PREGNANCY, not persisting after delivery

Question 2

what are risks associated with poor control of gestational diabetes?

Answer 2

1. macrosomic foetus (larger baby at birth)
2. stillbirth
3. increased rate of congenital defects

Question 3

how do you measure gestational diabetes?

Answer 3

oral glucose tolerance test

Question 4

when does lipid metabolism increase during pregnancy?

Answer 4

increase in lipolysis from T2

increase in plasma free fatty acids on fasting

Question 5

why is there an increase in lipolysis from T2?

Answer 5

free fatty acids provide substate for maternal metabolism, leaving glucose for foetus

Question 6

why is pregnancy associated with an increased risk of ketoacidosis?

Answer 6

too much fatty acids broken down as fuel

causing buildup of ketones

Question 7

what are the changes to thyroid metabolism during pregnancy?

Answer 7

thyroid binding globulin (TBG) production increased
T3 and T4 increased
(TBG binds to T3 and T4 in circulation)
free T4 in normal range

Question 8

how does hCG affect the thyroid?

Answer 8

hCG has direct effect on thyroid stimulating thyroid hormone production (TSH)
TSH can be decreased in normal pregnancies

Question 9

what are the anatomical changes to the GI system in pregnancy?

Answer 9

alterations in the disposition of the viscera

e.g. appendix moves to RUQ as uterus enlarges

Question 10

what are the physiological changes to the GI system?

Answer 10

SM relaxation by progesterone:
- GI: delayed emptying
- Biliary tract: stasis
- pancreas: increased risk of pancreatitis
(heart burn, constipation)

Question 11

what are the haematological changes during pregnancy?

Answer 11

pregnancy is pro-thrombotic state (clot more likely)
increased fibrinogen and clotting factors
reduced fibrinolysis

Question 12

what does pro-thrombotic state of pregnancy mean?

Answer 12

increase fibrin deposition at the implantation site (invasive process, help to clot)

Question 13

why is there an increased risk of thromboembolic disease in pregnancy?

Answer 13

venodilation - can lead to stasis of blood flow

added to increased clotting factors

Question 14

why can warfarin not be administered despite increased risk of thromboembolic disease?

Answer 14

warfarin crosses the placenta and is teratogenic

Question 15

why is there a risk of anaemia in pregnancy?

Answer 15

plasma volume increases
red cell mass increases, but not as much
(ratio of plasma volume to RBC)
PHYSIOLOGICAL anaemia

Question 16

aside from physiological anaemia, which other type of anaemia can occur?

Answer 16

anaemia due to Fe- and folate deficiency

due to increased iron demand of foetus

Question 17

what other anaemia can occur?

Answer 17

haemoglobinopathies

Question 18

what is haemoglobinopathies?

Answer 18

a kind of genetic defect that results in abnormal structure of one of the globin chains of the hemoglobin molecule. Hemoglobinopathies are inherited single-gene disorders; in most cases, they are inherited as autosomal co-dominant traits

Question 19

why isn’t the foetus rejected in pregnancy (immune system)?

Answer 19

foetus is an allograft

non-specific suppression of the local immune response at the materno-foetal interface

Question 20

if there is a defect in the transfer of antibodies (IgG) from mother to foetus, what can result?

Answer 20

1. haemolytic disease

2. graves disease and Hashimoto’s thyroiditis

Question 21

what is haemolytic disease?

Answer 21

attacks foetus RBC and destroys them

Question 22

why can graves disease and Hashimoto’s thyroiditis arise in foetus in utero?

Answer 22

antibodies destroying thyroid within mother transferred across placenta, destroying thyroid within foetus