8.2.2 Flashcards
Describe changes in thyroid hormones in pregnancy?
• hCG has a direct effect on the Thryoid, stimulating T3 and T4 production
o TSH can be decreased in normal pregnancies as a result of negative feedback from T3 and T4 produced due to hCG secretion
Describe anatomical changes and physiological changes in GI system in pregnancy.
Anatomical Changes
• Alterations in the positions of viscera
o E.g. appendix moves from RLQ to LUQ as the uterus enlarges
Physiological Changes
• Smooth muscle relaxation by Progesterone
o GI – Delayed emptying
o Biliary tract – Stasis
o Pancrease – Increased risk of pancreatitis
Why is pregnancy a pro-thrombotic state? Why can warfarin not be administered?
• High amount of fibrin deposition at the site of implantation
o Increased fibrinogen and clotting factors
o Reduced fibrinolysis
• Stasis, venodilation
• Results in Thromboembolic disease in pregnancy
o Cannot give warfarin – Crosses the placenta and is teratogenic
How does anaemia occur in pregnancy?
Plasma volume increases
RBC mass increases but not to same extent.
Physiological anaemia
Haematorit volume mismatch.
Anaemia due to folate deficiency Symptoms: Pale skin, lips, nails Tiredness SOB Dizziness
Significance of immune system in pregnancy?
• Fetus is an allograft
o Genetically different to the mother
• Non-specific suppression of the local immune response at the materno-fetal interface
• Transfer of antibodies
o IgG crosses the placenta
• Haemolytic disease
o Antibodies for ABO do not cross
o Antibodies of Rhesus do cross
• Graves disease and Hashimoto’s Thyroiditis
Antibodies will cross the placenta and either stimulate TSH receptors on or destroy developing fetal thyroid respectively.
What is measured in antenatal screening?
o History and examination • Risk factors – E.g. for gestational diabetes o Blood test • Blood group • Haemoglobin • Infection o Urinalysis • Protein
What is pre-exlampsia?
• Disorder of pregnancy characterised by high blood pressure and a large amount of protein in the urine.
BP>140/90
Proteinuria > 0.3g
When does pre-eclampsia/eclampsia occur?
T3
What happens in severe pre-eclampsia? When is it known as eclampsia?
o RBC breakdown o Low platelet count o Impaired liver function o Kidney dysfunction • If untreated, it may result in seizures at which point it is known as eclampsia.
Risk factors for pre-eclampsia?
Obesity
DM
Hypertension.
Treatment of pre-eclampsia?
Aspirin
Calcium
BP meds
Give the differences in CVS of normal and pre-eclampsia.
Normal Pregnancy
• Vasodilated
• Plasma-Expanded
• Blood pressure not raised in normal pregnancy
Pre-Eclamptic Pregnancy • Vasoconstricted • Plasma-Contracted • Raised blood pressure • Proteinuria • Pitting oedema
