Obstetric Haem Flashcards
Normal blood count changes in pregnancy
o Mild anaemia
Red cell mass rises (120-130%)
Plasma volume rises (150%)Net Dilution
o Macrocytosis
o Neutrophilia
o Thrombocytopenia (increased platelet size from increase in turnover of platelets)
Iron and Folate requirement for pregnancy
RDA of 30mg of iron- 60mg supplement given
Folate- 200mcg/day- 400mcg given supplement
What does IDA cause in pregnancy
IUGR, prematurity and PPH
Defining IDA in pregnancy
<110 in 1st
<105 2nd
<100 3rd
Causes of thrombocytopenia in pregnancy
1) Physiological (gestational or incidental thrombocytopenia)
(2) Pre-eclampsia (HELLP – Haemolysis, Elevated Liver enzymes, Low Platelets)
(3) Immune thrombocytopenia (ITP) – BM creates lots of platelets but there is peripheral destruction
(4) MAHA syndromes
Coagulation changes in pregnancy
Increase in factor 8, VWF, fibrinogen- pro-thrombotic
Decrease in protein S, increase in plasminogen activator inhibitor - less fibrinolysis
Risk factors for PE
High BMI >25- largest factor
Post-partum- most likely time for Thrombotic event
1st trimester
Treatment of ITP in pregnancy
o IVIG + steroids
o Anti-D (in RhD +ve mothers with spleen) – the anti-D coats the RBCs and is preferentially removed by the reticuloendothelial system in preference to the AB-covered platelets, thus conserving platelet levels
Treatment of Thromboembolic disease in pregnancy
LMWH (OD or BD) does not cross placenta
No Warfarin DOES CROSS PLACENTA (teratogenic), avoid weeks 6-12
Diagnosis of APLS
Miscarriages (≥3) + lupus anticoagulant or anticardiolipin antibodies
Treatment of APLS
Treat with (unfractionated) heparin and aspirin → dramatically improved outcomes
4 main causes of PPH
Tone, trauma, tissue, thrombin
Which leg do DVTs mainly occur in and why
Left due to compression
How DIC manifests in pregnancy
• Coagulation changes in pregnancy predispose to DIC (TF and factor 7a can come into contact and start the cascade)
With amniotic embolism and Pe-eclampsia precipitating decomposition
Haemoglobinopathy screening aims
o Alpha 0 thalassaemia / Hb Barts (4 gamma chains) - death in utero, hydrops fetalis
o Beta 0 thalassemia (transfusion dependent)
o HbSS / SCD (life expectancy 43yo)
o Other compound HbS syndromes – symptomatic, stroke
