8.2 Maternal problems in pregnancy (2) Flashcards
what is gestational diabetes?
carbohydrate intolerance first recognised in PREGNANCY, not persisting after delivery
what are risks associated with poor control of gestational diabetes?
- macrosomic foetus (larger baby at birth)
- stillbirth
- increased rate of congenital defects
how do you measure gestational diabetes?
oral glucose tolerance test
when does lipid metabolism increase during pregnancy?
increase in lipolysis from T2
increase in plasma free fatty acids on fasting
why is there an increase in lipolysis from T2?
free fatty acids provide substate for maternal metabolism, leaving glucose for foetus
why is pregnancy associated with an increased risk of ketoacidosis?
too much fatty acids broken down as fuel
causing buildup of ketones
what are the changes to thyroid metabolism during pregnancy?
thyroid binding globulin (TBG) production increased
T3 and T4 increased
(TBG binds to T3 and T4 in circulation)
free T4 in normal range
how does hCG affect the thyroid?
hCG has direct effect on thyroid stimulating thyroid hormone production (TSH)
TSH can be decreased in normal pregnancies
what are the anatomical changes to the GI system in pregnancy?
alterations in the disposition of the viscera
e.g. appendix moves to RUQ as uterus enlarges
what are the physiological changes to the GI system?
SM relaxation by progesterone: - GI: delayed emptying - Biliary tract: stasis - pancreas: increased risk of pancreatitis (heart burn, constipation)
what are the haematological changes during pregnancy?
pregnancy is pro-thrombotic state (clot more likely)
increased fibrinogen and clotting factors
reduced fibrinolysis
what does pro-thrombotic state of pregnancy mean?
increase fibrin deposition at the implantation site (invasive process, help to clot)
why is there an increased risk of thromboembolic disease in pregnancy?
venodilation - can lead to stasis of blood flow
added to increased clotting factors
why can warfarin not be administered despite increased risk of thromboembolic disease?
warfarin crosses the placenta and is teratogenic
why is there a risk of anaemia in pregnancy?
plasma volume increases
red cell mass increases, but not as much
(ratio of plasma volume to RBC)
PHYSIOLOGICAL anaemia
aside from physiological anaemia, which other type of anaemia can occur?
anaemia due to Fe- and folate deficiency
due to increased iron demand of foetus
what other anaemia can occur?
haemoglobinopathies
what is haemoglobinopathies?
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
why isn’t the foetus rejected in pregnancy (immune system)?
foetus is an allograft
non-specific suppression of the local immune response at the materno-foetal interface
if there is a defect in the transfer of antibodies (IgG) from mother to foetus, what can result?
- haemolytic disease
2. graves disease and Hashimoto’s thyroiditis
what is haemolytic disease?
attacks foetus RBC and destroys them
why can graves disease and Hashimoto’s thyroiditis arise in foetus in utero?
antibodies destroying thyroid within mother transferred across placenta, destroying thyroid within foetus
