Haematology 11: Obstetric Haematology Flashcards
Why are pregnant women anaemic despite an average Red cell mass increase of 120-130% ?
Plasma volume increases by 150% causing a net dilution
What is the WHO recommended daily Iron and folate supplementation for pregnant women ?
60mg iron
400mcg folate
What are pregnant women with thrombocytopenia at risk of when receiving epidural anaesthesia?
Spinal haematoma
What happens to platelets in pregnancy ?
They become larger
They are sometimes counted as RBCs by the FBC machine
List 4 causes of thrombocytopenia in pregnancy ?
Gestational thrombocytopenia (physiological)
Placenta praevia
ITP
MAHA
List 4 causes of MAHA ?
TTP- thrombotic Thrombocytopaenia purpura
HUS- Haemolytic uraemic syndrome
HELLP - haemolysis elevated liver enzymes and low platelets
Pre eclampsia
Why does pregnancy induce a net procoagulant state ?
To rapidly control bleeding at the placental site after delivery
Which anticoagulant factor falls to half the normal level during pregnancy ?
Protein S
Which coagulation factors increase the most during pregnancy ?
Factor VIII and vWF (3-5 fold)
Other factors that increase: Fibrinogen (2 fold) and factor VII (0.5 fold)
Which antifibrolytic factors increase during pregnancy ?
PAI-1 and 2
Which antifibrinolytic factor is produced by the placenta during pregnancy ?
PAI-2
During pregnancy the body assumes a ……….coagulant and ………… fibrinolytic state
Hypercoagulant
Hypofibrinolytic
Is D-dimer useful for exclusion of DVT in pregnancy ?
No
D-dimer is physiologically elevated in pregnancy
Which autoantibody is present in APLS ?
Anti-cardiolipin antibodies
Which 2 medications are recommended in APLS ?
LMWH + aspirin
Give 3 indications for testing for APLS ?
- 3 or more consecutive miscarriages <10 weeks gestation
- 1 morphological normal foetal loss > 10 weeks gestation
- 1 or more preterm births before 34 weeks gestation thought to be due to placental disease
What is placenta accreta ?
When the placenta goes through the endometrial lining (becomes difficult to deliver)
What is placenta increta ?
The placenta goes through the uterine wall
What is placenta percreta ?
Placenta goes through the uterine wall and attaches to other organs
What is a risk factor for placenta accreta ?
Previous C section
What is a complication of placenta accreta ?
PPH/ MOH
Define post partum haemorrhage (PPH) ?
> 500ml blood loss in the first 24 hours of pregnancy
What are the 4Ts of causes of PPH ?
Tone - uterine atony
Tissue- placenta accreta
Trauma- instrumental delivery
Thrombin- DIC
How does amniotic fluid embolism present ?
Sudden onset shivers, vomiting, shock and DIC
Which modality is used to diagnose haemoglobin variants ?
HPLC (high power liquid chromatography)
Elevated HbA2 >3.5% suggests which thalassaemia ?
Beta thalassaemia
How are pregnant women with sickle cell disease managed ?
Top up or exchange red cell transfusions
prophylactic transfusions
Alloimmunisation (make sure the blood is matched)
