Incidental thrombocytopenia of pregnancy and thrombocytopenia
resulting from pre-eclampsia are the two most common
platelet disorders of pregnancy. Primary (idiopathic
thrombocytopenic purpura [ITP]) or secondary (immune-mediated
thrombocytopenia) may also occur, but are less common.13
Incidental Thrombocytopenia of Pregnancy
Incidental thrombocytopenia is the most likely cause
of platelet dysfunction in pregnancy, occurring
in an estimated 5% to 7% of pregnancies at term.
It is a benign condition that poses no risk for
neonatal thrombocytopenia.13
Pre-eclampsia
Pre-eclampsia is a common hypertensive disorder
of pregnancy affecting 7% to 10% of pregnancies.
It is defined by hypertension and proteinuria that
occur between 20 weeks of gestation and 4 weeks
after delivery. Approximately 10% to 20% of pre-eclamptic
women develop thrombocytopenia. Pre-clampsia is
severe in as many as 50% of cases.13
Clinical Description
The cause of thrombocytopenia in preeclampsia is
due to increased platelet destruction. It is not
unlikely for some patients to also present with
platelet dysfunction, characterized by disproportionately
long bleeding times, as well as defective in
vitro thromboxane synthesis.14
The pathogenisis of thrombocytopenia
in pre-eclampsia still has not been completely identified.
To learn more about evaluating platelet dysfunction
in pregnancy, click
here.
For information on Drug-Induced Platelet Dysfunction,
click
here.
