Hematological disorders in pregnancy

1. Hematological disorders in
pregnancy

2. Contents
 This lecture will discus :
anemia
hemoglobinopathies (sickle cell and thalassemia )
bleeding disorders and platelets disorders
Please note that this lecture was made for internship exam of the JMA, further
readings might be needed for more advanced exams

3. Anemiain
pregnancy
Anemia is the most common medical disorder in pregnancy
complicating 30-50 % of pregnancies
Most common anemia is iron deficiency anemia accounts for
90 % of anemias in pregnancy
Folic acid deficiency accounts for 5 % while B12 deficiency
anemia is rare in pregnancy
Cut off Hb to diagnose anemia is 11g-dl for the first trimester
, 10.5 g-dl for the second and third trimester
In low risk patients with singleton pregnancy Hb should be
checked at booking and again at 28 weeks

4. Irondeficiency
anemia
IDA
 Diagnosis :
least accurate in pregnancy : microcytic , hypochromic RBC (low mcv
, MCH , MCHC)
The most accurate in pregnancy : Low serum ferritin level less or equal
to 15 mcg/dl
 Treatment : (trial of oral iron for 2 weeks )
Once anemia is diagnosed oral iron is to be started if suitable , recheck
Hb in 2 weeks , if no rise in Hb; ferritin level is should be measured
(unselected screening of ferritin is not recommended )
Treatment is by ferrous salts (oral ) 100-200 mg elemental iron daily
Treatment with iron is not suitable for diagnosed anemia of non iron
deficiency cause
IV iron is only given in some cases as malabsorption , non compliance
to oral iron ,very late in pregnancy and shouldn’t be given in the first
trimester , renal and liver diseases , rheumatoid arthritis

5. Factorsaffecting
ironabsorption

6. Complications
ofIDA
 Preterm labor
 Infections
 Postpartum hemorrhage
 Risk of blood transfusion after delivery
 IUGR

7. Preventionof
IDA
 Balanced diet
 Prophylactic iron Supplements ??( not for all )
 Selected ferritin screening as people at risk of
bleeding, and treatment with oral iron if level
decreased below 30 mcg-L with dose of at least 65
mg elemental iron and to be checked again (Hb and
ferritin ) in 8 weeks

8. Hemoglobinopathies

9. globingenes

10. BThalassemia
 Thalasemia is the most common genetic blood disorder
 The beta-thalassaemias result from defects in the normal
production of the beta chains o n chromosome 11
 Autosomal recessive :
if both partners have beta-thalassaemia minor, there is a 1:4
chance the fetus could have beta-thalassaemia major,
which is associated with profound anaemia in postnatal life

11. Classificationof
Bthalassemia
 According to the number of genes that has a defect
 HbA which is normal hemoglobin is decreased
(intermediate )or absent (major ) while Hb A2 and HbF
increased

12. AThalassemia
 A defect in A globin gene on chromosome 16
 According to the number of genes deleted

13. Thalassemiain
pregnancy
 Women are at risk of infertility (iron accumulation on
pituitary ) , cardiomyopathies , endocrinopathies
(hypothyroidism and DM ) and osteoporosis
 Fetal risk of IUGR (serial growth scan is needed )
 Antenatally screen for end organ failure : dexa scan for
osteoporosis , serum fructosamine for DM , LFT , liver US
and MRI for gall stones and iron load , heart echo, ECG
and MRI
 In addition to the recommended vaccines in pregnancy ,
splenectomised women should receive vaccines as HBV,
pneumococcal (every5 years ) , meningiococcal and
Hemophilus influenza once if they didn’t receive it before
+ pencilline

14. Thalassemiain
pregnancy
 High dose folic acid 5 mg
 Aspirin and LMWH in some cases (splenectomised with
high platelets count )
 Keep hemoglobin more than 10 g-dl (infuse blood if less )
 Iron chelators should not be given during pregnancy and
3 months before pregnancy except desferoxamine that
can be given after 20 weeks
 Iron chelator iv deferoxamine should be given during
labor
 During labor prepare blood and do a continuous CTG
 Postnatally deferoxamine is safe in breast feeding
 Postnatally patients should receive LMWH

15. Sicklecell
anemia
Autosomal recessive disorder on chromosome 11
Substitution of amino acid glutamine for valine in beta globin chain on
b globin gene lead to RBC precipitating in when hb is reduced
(hypoxia ) forming HbS
Precipitated hemoglobin leads to a state of hemolysis and blockage of
capillaries (hypoxic crisis and ischemia of organs )
There is sever anaemia, chronic hyperbilirubinaemia, a predisposition
to infection, vasoocclusive
complications including the acute chest syndrome, and CKD

16. Pregnancywith
sicklecell
anemia
 Pregnancy management is the same as thalassemia
regarding aspirin , LMWH , folic acid and fetal growth
serial scanning (see thalassemia )

17. Sicklecell
complications
 Sickle cell trait has a risk of urinary tract infections and
endometritis
 Sickle cell carriers have a 1:4 risk of having a baby with
SCD if their partner also has sickle cell trait. Carriers are
usually fit and well, but are at increased risk of urinary
tract infection, and rarely suffer from crises
 Sickle cell anemia : infections , bleeding , preterm labor ,
PET , IUGR, miscarriage
 Painful crisis (acute chest syndrome ) and VTE (strokes ,
deep venous thrombosis , PE )
 Acute chest syndrome accounts for 25 % of all death in
sickle cell disease

18. Treatment
 Exchange transfusion of blood in acute chest syndrome ,
multiple pregnancy , stroke
 Top up blood transfusion in anemia
 Acute chest syndrome is managed by admission , pain
killers ,exchange transfusion , LMWH while admitted , o2 ,
rule out chest infection and PE
 Stroke is managed by thrombolytics , and exchange
transfusion

20. Postpartum
 Postpartum management of sickle cell is like thalassemia
where LMWH is given
 Contraception allowed in sickle cell paitents are POP ,
DMPA (decrease crisis )
 OCP and IUCD are category 2 , not preferred due to the
risk of VTE(COC) and infections (IUCD)

21. THROMBOCYTOPENIA
Platelets count <150 × 109/l.
Causes :
 increased consumption or destruction;
 autoimmune; ITP
 antiphospholipid syndrome;
 pre-eclampsia;
 HELLP syndrome;
 disseminated intravascular coagulation;
 thrombotic thrombocytopaenic purpura;
 hypersplenism.
 sepsis;
 HIV infection;
 malignant marrow infiltration.

22. Gestational
thrombocytopenia
 Occur in 8 % of pregnancies
 Mostly no complications
 Almost Never less than 70 *109/ l (usually 100-150 )
 Occur due to increased destruction of platelets
 A diagnosis of exclusion
 Resolved spontaneously after labor
 No fetal effect (no need for fetal monitoring )
 Needs follow up of platelets count
 no treatment is needed

23. ITP
IMMUNE
THROMBOCYTOPENIC
PURPURA
 Autoimmune thrombocytopaenia (autoantibodies are
produced against platelet surface antigens, leading to
platelet destruction)
 Complications :
Post partum hemorrhage (count less than 50 *109)
Spontaneous bleeding (count less than 20 *109)
Fetal thrombocytopenia (5-10 %)
First line treatment is prednisolone (steroid ) takes 3
weeks for the effect
Second line treatment is IVIG (if rapid rise needed)
Aim of treatment is to keep platelets more than 50

24. DeliveryinITP
 Aim of steroid therapy is to keep platelets more than 20 early
in pregnancy and more than 50 late in pregnancy and during
labor
 Not an indication for cesarean
 Blood should be prepared and active management of third
stage of labor should be resumed with prophylactic steps to
reduce blood loss during cesarean section if needed
 Regional anesthesia as spinal and epidural is
contraindicated if platelets count is less than 80*109
 Fetal blood sampling in labour and instrumental delivery by
ventouse are best avoided because of the risk of fetal
thrombocytopaenia (5-10 %)
 Fetus should receive oral vitamin K instead of IM until the
disease is excluded (nadir neonatal platelets at 2-5 days )

25. TTP vsHUS

26. Inherited
coagulation
disorders

27. Inherited
coagulation
disorders
 Von Willebrand disease, carriers of haemophilia A and B and factor
XI deficiency account for over 90% of all women with inherited
bleeding disorders.
 The most common is Von Willebrand disease 1%
(AD type 1 ,2 and AR type 3 ) improves in pregnancy
 Hemophilia A (factor 8 def.) AR improves in pregnancy
 Hemophilia B (factor 9 def.) AR doesn’t improve in pregnancy
 In haemophilia carriers, tests to confirm fetal sex should be offered
 Follow up of factor 8 level is needed (and activity in vonwilbrand) and
should be above 50 mg-dl during labor or before any procedure

28. Hemophilia
Classification

29. Delivery?
 They are at risk of postpartum hemorrhage so
prophylactic measures should be taken
 If level decreased below 50 mg treatment should be given
as desmopressin (DDAVP) which increases factor 8
levels (only used in hemophilia 8 and vonwilbrand type 1
and 2 a )
 Cryoprecipitate or factor 8 concentrate is needed in
hemophilia B , vonwilbrand disease type 2b and 3
 tranexamic acid used prophylactically to decrease blood
loss during and after labor
 Invasive fetal monitoring, ventouse and rotational forceps
should be avoided if there is a possibility that the fetus
may be affected
Not an indication for CS

30. DIC
 Disseminated intravascular coagulopathy
 Always acquired (never primary nor congenital)
 a syndrome characterized by massive activation and
consumption of coagulation proteins, fibrinolytic proteins
and platelets

31. CausesofDIC

32. DiagnosisofDIC
 Symptoms and Signs
Bleeding
Multiple bleeding sites
Ecchymoses of skin, mucous membranes
Visceral hemorrhage
Ischemic tissue
Hypotension or shock
Organ dysfunction
Lab findings :
Thrombocytopenia (low platelets )
Low fibrinogen
High FDP, high D-dimer
Low coagulation factors as factor 8 and 5
Antithrombin III decreased
PT, PTT INR increases

33. Treatment
Treat the underlying cause
Replacement therapy with blood and blood components Fresh
frozen plasma, Cryoprecipitate, Platelet transfusions
 Aim is to keep Hb more than 8 g-dl , platelets above 50*109/ l
,fibrinogen above 2g/L , PT PTT less than 1.5 above the normal
 Start platelets transfusion when platelets below 75 *109 with active
bleeding
 Start FFp (15ml/kg) when PT , PTT are 1.5 times with active bleeding
 Start cryo when fibrinogen is less than 2g/L with active bleeding
 Blood transfusion is a clinical judgment and usually needed when Hb
lower than 6