Thrombocytopenia during pregnancy

1. Thrombocytopenia
During pregnancy
Prof Aboubakr Elnashar
Benha university Hospital, Egypt
Aboubakr Elnashar

2. Causes
1. Spurious result (reduced platelets on automated
Coulter counter {platelet clumping or misreading
of large immature platelets as red cells}
2. Gestational thrombocytopenia
3. Immune thrombocytopenic purpura (ITP)
4. Pre-eclampsia and Haemolysis, Elevated Liver
enzymes and Low Platelets (HELLP) syndrome
5. Disseminated intravascular coagulation (DIC)
Aboubakr Elnashar

3. 6. Haemolytic uraemic syndrome (HUS) /thrombotic
thrombocytopenic purpura (TTP)
7. Sepsis
8. Human immunodeficiency virus (HIV), drugs and
infections (e.g. malaria)
9. Systemic lupus erythematosus (SLE) and
antiphospholipid syndrome (APS)
10. Bone marrow suppression.
Aboubakr Elnashar

4. Incidence
 5-10%: of pregnant women
Gestational' thrombocytopenia:75%
Chronic ITP:
1-2/10,000 pregnancies.
usually affects young Women
female to male ratio = 3:1
Aboubakr Elnashar

5. AIloimmune thrombocytopenia
fetal disorder
{fetomaternal incompatibility for platelet antigens
(similar to Rhesus haemolytic disease of the
newborn)}
No maternal symptoms and the mother is not
thrombocytopenic.
The condition develops in utero, affects all children
including the firstborn, but is usually (except in the
case of Subsequent siblings) diagnosed after birth.
Incidence: 1 in 2000
causes 10% of all cases of neonatal
thrombocytopenia.
Aboubakr Elnashar

6. Clinical features
Gestational thrombocytopenia:
Benign condition
platelet count <100 x 109/L: no adverse
consequences for mother or baby.
Thrombocytopenia in the first half of pregnancy:
less likely to be gestational: possible diagnosis of
ITP.
Aboubakr Elnashar

7.  ITP
Isolated thrombocytopenia without any associated
haematological abnormality.
No splenomegaly or lymphadenopathy.
Haemorrhage: unlikely with platelet counts >50 x
109/L
Spontaneous haemorrhage without surgery:
unlikely with counts >20 x 109/L.
±skin bruising or gum bleeding
severe haemorrhage: rare.
Aboubakr Elnashar

8. Pathogenesis
Gestational thrombocytopenia
Normal pregnancy: Platelet count fall progressively
5% to 10%: thrombocytopenic levels (50-150 x
109/L) by term.
 ITP
Autoantibodies against platelet surface antigens:
peripheral platelet destruction by the
reticuloendothelial system, particularly the spleen.
Aboubakr Elnashar

9. Diagnosis
ITP
By exclusion: other causes (infection and PET)
Bone marrow:
normal or megakaryocytic
not necessary in pregnancy in cases of isolated
thrombocytopenia unless it is severe (platelet count
<30 x 109/L)
Antiplatelet antibody:
not readily available
not helpful {absence of antiplatelet antibodies does
not exclude the diagnosis of ITP.}
Aboubakr Elnashar

10. Effect of pregnancy on ITP
Pregnancy does not affect the course of ITP
Anxieties arise around the time of delivery
{possible bleeding associated with
vaginal and abdominal delivery and
regional anaesthesia and analgesia}.
Aboubakr Elnashar

11. Effect of ITP on pregnancy
Capillary bleeding and purpura:
unlikely with a platelet count of >50 x 109/L
Spontaneous mucous membrane bleeding:
not a risk with platelet counts >20 x 109/L.
Aboubakr Elnashar

12. Antiplatelet IgG can cross the placenta: fetal
thrombocytopenia.
Prediction of the fetal platelet count from
maternal platelet count
antibody level or
splenectomy status: not possible
Fetal platelet counts <50 x 109/L:
5% to 10%
10-15% in:
ITP before pregnancy
symptomatic ITP in the index pregnancy.
Aboubakr Elnashar

13. Antenatal or neonatal intracranial haemorrhage
0% to 1.5%
lowest in the absence of
maternal symptoms or a history of ITP prior to the
index pregnancy.
One of the best predictors of severe neonatal
thrombocytopenia is a previously affected child
Incidence of serious haemorrhage in the fetus and
neonate: low.
Aboubakr Elnashar

14. Management
Gestational thrombocytopenia
Benign condition: no intervention.
Aboubakr Elnashar

15. ITP
Maternal considerations
Exclude associated conditions:
SLE (ANA, double stranded DNA, smith) or
APS.
The platelet count should be monitored
monthly and then more frequently in 3rd T: therapy
can be instituted if required prior to delivery.
Treatment is only required in 1st and 3rd T:
The woman is symptomatic with bleeding
The platelet count is <20 x 109/L
The count needs to be increased prior to a
procedure such as chorionic villous sampling (CVS)
Aboubakr Elnashar

16. Counts:
<50 x 109/L (even in the absence of bleeding):
prophylactic treatment prior to delivery.
50 to 80 x 109 /L
may warrant treatment prior to delivery {facilitate
safe regional analgesia}.
Aboubakr Elnashar

17. CS:
only required for obstetric indications
Epidural and spinal anaesthesia:
safe with stable counts >75 to 80 x 109/L.
Bleeding time does not predict haemorrhage and is
not indicated‘
Aboubakr Elnashar

18. Corticosteroids:
first-line therapy
Prednisolone dose:
Non pregnant:
(60-80 mg/d, 1 mg/kg/d)
Pregnancy:
lower doses (20-30 mg/d): safe and effective.
then dose may be weaned to the lowest that will
maintain a satisfactory (>50 x 109/L) maternal
platelet count
Aboubakr Elnashar

19. IV immunoglobulin (IVIg)
Indication:
resistant cases
women likely to require prolonged therapy
women requiring a high maintenance dose of
prednisolone or
who are intolerant of prednisolone.
 Mechanism:
delaying clearance of IgG-coated platelets from the
maternal circulation.
Aboubakr Elnashar

20. Response:
more rapid (24-48 h) than with steroids: useful if a
rapid response is required.
lasts for two to three weeks
Disadvantages:
Expensive
seldom produces long-term remission.
Dose:
0.4 g/kg/ day for five days or 1 g/kg over eight hours,
repeated two days later if there is an inadequate
response.
Aboubakr Elnashar

21. Anti-D immunoglobulin
Indication:
non-splenectomised rhesus-positive women.
Mechanism:
creating a decoy to competitively inhibit the
destruction of antibody-coated platelets: raise platlet
count.
Doses: IV bolus
50 to 70 µg/kg.
Safe and effective in 2nd and 3rd T.
Monitor baby
neonatal jaundice
anaemia, and
direct antiglobulin test positivity after delivery.
Aboubakr Elnashar

22. Splenectomy
should be avoided in pregnancy if possible
May be necessary in extreme cases.
Performed in the second trimester and can at this
stage be performed laparoscopically.
Women with ITP who have previously been treated
with splenectomy should continue penicillin
prophylaxis throughout pregnancy.
Aboubakr Elnashar

23. Other options for women who fail to respond to
oral prednisolone and IVIg
i.v. methylprednisolone
azathioprine or ciclosporin.
danazol and vincristine: Although not recommend
have been successfully used for severe resistant
cases in pregnancy.
Aboubakr Elnashar

24. Platelet transfusions
last resort for bleeding or
prior to surgery
increase antibody titres
do not result in a sustained increase in platelet
counts.
Aboubakr Elnashar

25. Fetal considerations
No place for serial fetal blood samples earlier in
gestation {Transfer of IgG increases at the end of
pregnancy and the baby is not at risk of bleeding
before labour and delivery}
The risk of fetal blood sampling via cordocentesis
(cord spasm, haemorrhage from the cord puncture
site) is similar (or even higher in thrombocytopenic
fetuses) to the risk of intracerebral haemorrhage
(ICH).
Aboubakr Elnashar

26. CS:
only indicated for obstetric reasons.
{no conclusive evidence that SC reduces the
incidence of ICH, or that it is less traumatic for the
fetus than vaginal delivery}
Aboubakr Elnashar

27. Neonatal consideration
Cord platelet count is determined immediately
after delivery
Neonatal platelet count:
only reaches a nadir after two to five days in affected
infants {splenic circulation is established}: most
hemorrhagic events in neonates occur 24-48h after
delivery at the nadir of the platelet count: monitoring
is necessary over this time.
IVIg
the recommended treatment for neonates with
bleeding or severe thrombocytopenia; this may be
given prophylactically if the platelet count of the cord
blood is low «20 x 109 /L).
Aboubakr Elnashar

28. Conclusion
ITP
The diagnosis of ITP is one of exclusion and
should only be made once other causes of
thrombocytopenia have been excluded.
Bleeding is unlikely if the platelet count is >50 x
109/L.
The risk of serious thrombocytopenia and
haemorrhage in the neonate from transplacental
passage of antiplatelet IgG is low.
 CS is only required for obstetric indications and
epidural and spinal anaesthesiajanalgesia are safe
with stable counts >75 to 80 x 109/L.
Treatment, if required, should be with
corticosteroids or IVIg). Aboubakr Elnashar

29. History and
Physical
Normal
Repeat
platlet count
normal
- Assume lab error
- No further
workup
1st T platlet count low
Assume ITP
Counsel: risks of neonatal thrombocytopenia
Inform anesthesia and pediatric staff
Ensure no spontaneous bleeding
Ensure platelets >50K at delivery
1st T platlet
count
normal
Assume gestational
thrombocytopenia: no
further work up
Abnormal
Aboubakr Elnashar

30. Abnormal
History of
medications
-Alternative
medication
- Counsel maternal
an fetal risk
Evidence of
systemic
disease
Management depend on type of
illness e.g. self limiting viral
illness or ch rheumatologic dis
Elevated BP
with normal
BP in 1st T
Assume hypertensive
disorder of pregnancy
Management depend on
gest age and s and s of
maternal and f disease
Aboubakr Elnashar

31. Thanks
Aboubakr Elnashar