The pregnancy may activate flares of certain autoimmune diseases such as lupus. The influence of pregnancy on the evolution of ITP was never studied while this pathology affects firstly women old enough to procreate. Also, the influence of ITP on pregnancy (risk of obstetric complications) and on newborns (risk of neonatal thrombocytopenia) is rather unknown and never studied in a prospective study. The realization of a prospective study to answer these questions is necessary to allow us to inform better the patients affected by ITP and to define better in this context the strategy of supervision of the mother, the foetus and the newborn. The highlighting of risk factors of ITP flare or obstetric or neonatal complications will indeed allow the implementation of prevention measures.

The conclusions of this study will allow us to adapt national guidelines for ITP during pregnancy.

1. Pregnant ITP women Inclusion Criteria

   • Women more than 18 years old
   • Primary ITP diagnosis, defined according to international criteria of 2009 consensus conference (isolated thrombocytopenia <100 G/L)
   • And pregnancy diagnosis after ITP diagnosis
   • Information notice delivered to women with non opposition to participation to the study Exclusion Criteria
   • Secondary ITP (according to 2009 consensus conference)
   • Severe comorbidity making difficult women's following

2. Control ITP Women (Non pregnant) Inclusion Criteria

   • Women more than 18 years old
   • Primary ITP diagnosis, defined according to international criteria of 2009 consensus conference (isolated thrombocytopenia <100 G/L)
   • Non pregnant (> 12 months of precedent pregnancy)
   • (Matched on age+/- 5 years old: suppress by amendment n°3 20170117), phase and status of ITP, and history of splenectomy
   • Information notice delivered to women with non opposition to participation to the study Exclusion Criteria
   • Secondary ITP (according to 2009 consensus conference)
   • Severe comorbidity making difficult women's following

3. De novo ITP pregnant women Inclusion Criteria

   • Women more than 18 years old
   • Pregnant
   • With a newly diagnosed thrombocytopenia <50G/L, after elimination of others thrombocytopenia etiologies during pregnancy: gestational thrombocytopenia, preeclampsia, HELLP syndrome, ….
   • Information notice delivered to women with non opposition to participation to the study Exclusion Criteria
   • Secondary ITP (according to 2009 consensus conference)
   • Severe comorbidity making difficult women's following
   • Non confirmation of ITP diagnosis in post-partum

Patients from French referral centers for immune Thrombocytopenia