Search Elevated Serum Alkaline Phosphatase as a Marker of Prenatal Intervillositis Chronic Histiocytic

Inclusion Criteria: * Patient aged 18 years or more * Having signed a free and informed consent * Enjoying a social security scheme Inclusion criteria for cases: * Patient who gave birth at the Lille University Hospital between 2000 and 2009. * Lesion of intervillositis chronic histiocytic (IHC) diagnosed during histological examination of the placenta. * An alkaline phosphatase assay during pregnancy is available and has been achieved at University Hospital of Lille. * Prior information and not opposition of the patient to the secondary use of data collected in medical file. Inclusion criteria for low-risk pregnancy : * No pathological obstetric history, no current pregnancy complications * Followed antenatal clinics at the Lille University Hospital * A gestational age corresponding to one of the cases (pairing ± 1 week) * No chronic intervillositis after pathological examination of the placenta Inclusion criteria for high-risk pregnancy: * Patient hospitalized in the maternal-fetal pathology of the Lille University Hospital Service * Presence of IUGR, Death in Utero or severe preeclampsia with fetal repercussion * A gestational age corresponding to one of the cases (pairing ± 1 week) * No chronic intervillositis after pathological examination of the placenta Exclusion Criteria: * Twin pregnancy * Liver disease in the interrogation * Lack of consent of the patient * Patient not covered by a social security scheme * Patient minor * Patient under guardianship