Haem: Obstetric Haematology Pt.1 Flashcards
What haematological changes are seen on FBC in pregnancy?
- Mild anaemia (DILUTION)
- Red cell mass rises (120-130%)
- Plasma volume rises (150%)
- Macrocytosis
- Normal
- Folate or B12 deficiency
- Neutrophilia
- Thrombocytopenia
- Increased platelet size
What are the 3 Hb thresholds for anaemia in pregnancy?
<110 in 1st trimester
<105 in 2nd/ 3rd trimester
<100 post partum
What are the increased demands required in pregnancy?
- Iron requirement
- 300mg for fetus
- 500mg for maternal increased red cell mass
- Folate requirements increase
- Growth and cell division
- Approx additional 200mcg/day required
How iron deficiency diagnosed?
What is the treatment for iron deficiency in pregnancy?
FBC: Low Hb, MCV < 80
200 mg ferrous sulfate daily for 3 months
What does iron deficiency during pregnancy increase risk of?
IUGR
Prematurity
Postpartum haemorrhage
What is normal iron absorption per day?
What is iron absorption during pregnancy?
Normal absorption 1-2mg a day.
This increases to 6mg during pregnancy.
Why is iron absorption increased during pregnancy?
Hepcidin decreases and ferroportin levels increase. This results in increased iron absorption.
What are the RCOG recommendation for daily folate intake?
400 mcg daily
What does folate deficiency increase risk of during pregnancy?
Neural tube defects
What is the cut off level of platelets required for:
- Epidural anaethesia
- Delivery
- > 70 x10^9/L
- > 50 x10^9/L
Higher for epidural due to serious risk of spinal haematoma
What are causes of thrombocytopenia in pregnancy?
- Physiological:
- ‘gestational’ / incidental thrombocytopenia
- Pre-eclampsia
- Immune thrombocytopenia (ITP)
- Microangiopathic syndromes
- All other causes: bone marrow failure, leukaemia, hypersplenism, DIC etc.
What is the most commone cause of thrombocytopaenia <150x109/L in pregnancy?
Gestational thrombocytopenia
What is the most common cause of thrombocytopaenia <100x109/L in pregnancy?
ITP and pre-eclampsia
This suggests something pathological is occurring.
What is gestational thrombocytopenia?
A physiological decrease in platelet count of about 10% during pregnancy
Does not affect foetus.
What is the underlying mechanism of gestational thrombocytopenia?
Mechanism poorly defined.
Possibly due to dilution and increased consumption.