Table 2 Differential diagnosis of... | American Society of Hematology

Table 2

Differential diagnosis of gestational thrombocytopenia versus ITP

Characteristic	Gestational thrombocytopenia	ITP
Onset during pregnancy	Mid-late second trimester and third trimester	Anytime
	Frequency increases as term approaches
Evidence for alternative etiologies	No	No
Platelet count, × 10⁹/L	> 50*	Any < 100
	Progressively decreases as term approaches
Thrombocytopenia outside of pregnancy	No	Possible
Neonatal thrombocytopenia	No	Possible†
Postpartum resolution	Yes	Possible

Characteristic	Gestational thrombocytopenia	ITP
Onset during pregnancy	Mid-late second trimester and third trimester	Anytime
	Frequency increases as term approaches
Evidence for alternative etiologies	No	No
Platelet count, × 10⁹/L	> 50*	Any < 100
	Progressively decreases as term approaches
Thrombocytopenia outside of pregnancy	No	Possible
Neonatal thrombocytopenia	No	Possible†
Postpartum resolution	Yes	Possible

Rare cases have been reported with platelet counts at term 40-50 × 10⁹/L.

A total of 10% of infants have platelet counts < 50 × 10⁹/L.