Haematology 11: Obstetric Haematology

Question 1

Why are pregnant women anaemic despite an average Red cell mass increase of 120-130% ?

Answer 1

Plasma volume increases by 150% causing a net dilution

Question 2

What is the WHO recommended daily Iron and folate supplementation for pregnant women ?

Answer 2

60mg iron

400mcg folate

Question 3

What are pregnant women with thrombocytopenia at risk of when receiving epidural anaesthesia?

Answer 3

Spinal haematoma

Question 4

What happens to platelets in pregnancy ?

Answer 4

They become larger

They are sometimes counted as RBCs by the FBC machine

Question 5

List 4 causes of thrombocytopenia in pregnancy ?

Answer 5

Gestational thrombocytopenia (physiological)
Placenta praevia
ITP
MAHA

Question 6

List 4 causes of MAHA ?

Answer 6

TTP- thrombotic Thrombocytopaenia purpura
HUS- Haemolytic uraemic syndrome
HELLP - haemolysis elevated liver enzymes and low platelets
Pre eclampsia

Question 7

Why does pregnancy induce a net procoagulant state ?

Answer 7

To rapidly control bleeding at the placental site after delivery

Question 8

Which anticoagulant factor falls to half the normal level during pregnancy ?

Answer 8

Protein S

Question 9

Which coagulation factors increase the most during pregnancy ?

Answer 9

Factor VIII and vWF (3-5 fold)

Other factors that increase: Fibrinogen (2 fold) and factor VII (0.5 fold)

Question 10

Which antifibrolytic factors increase during pregnancy ?

Answer 10

PAI-1 and 2

Question 11

Which antifibrinolytic factor is produced by the placenta during pregnancy ?

Answer 11

PAI-2

Question 12

During pregnancy the body assumes a ……….coagulant and ………… fibrinolytic state

Answer 12

Hypercoagulant

Hypofibrinolytic

Question 13

Is D-dimer useful for exclusion of DVT in pregnancy ?

Answer 13

No

D-dimer is physiologically elevated in pregnancy

Question 14

Which autoantibody is present in APLS ?

Answer 14

Anti-cardiolipin antibodies

Question 15

Which 2 medications are recommended in APLS ?

Answer 15

LMWH + aspirin

Question 16

Give 3 indications for testing for APLS ?

Answer 16

• 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

Question 17

What is placenta accreta ?

Answer 17

When the placenta goes through the endometrial lining (becomes difficult to deliver)

Question 18

What is placenta increta ?

Answer 18

The placenta goes through the uterine wall

Question 19

What is placenta percreta ?

Answer 19

Placenta goes through the uterine wall and attaches to other organs

Question 20

What is a risk factor for placenta accreta ?

Answer 20

Previous C section

Question 21

What is a complication of placenta accreta ?

Answer 21

PPH/ MOH

Question 22

Define post partum haemorrhage (PPH) ?

Answer 22

> 500ml blood loss in the first 24 hours of pregnancy

Question 23

What are the 4Ts of causes of PPH ?

Answer 23

Tone - uterine atony
Tissue- placenta accreta
Trauma- instrumental delivery
Thrombin- DIC

Question 24

How does amniotic fluid embolism present ?

Answer 24

Sudden onset shivers, vomiting, shock and DIC

Question 25

Which modality is used to diagnose haemoglobin variants ?

Answer 25

HPLC (high power liquid chromatography)

Question 26

Elevated HbA2 >3.5% suggests which thalassaemia ?

Answer 26

Beta thalassaemia

Question 27

How are pregnant women with sickle cell disease managed ?

Answer 27

Top up or exchange red cell transfusions
prophylactic transfusions
Alloimmunisation (make sure the blood is matched)