Fetal alloimmune thrombocytopenia: is less invasive antenatal management safe?

Abstract

Objectives. The aim of this study was to review recent multicenter data on antenatal management of anti-HPA-1a fetal alloimmune thrombocytopenia and, based on this retrospective study and on recent literature, to evaluate if FBS modified the obstetrical management.

Material and methods. This retrospective study in France includes 23 pregnancies in 21 women who had a previous thrombocytopenic infant due to anti HPA-1a alloimmunization. All pregnant women received intravenous immunoglobulin (IVIG) treatment, with or without corticosteroids. Fetal blood sampling (FBS) was performed before any therapy (four cases) or during pregnancy (nine cases).

Results. Infants whose mother received treatment had a significantly higher neonatal platelet count than the corresponding sibling (p = 0.003). In eight cases, therapy was started late during pregnancy. In three cases, treatment was discontinued 3 or 4 weeks before birth, and this was associated with a poorer result. No in utero intracranial hemorrhage was recorded in the infants for whom maternal therapy continued to term. Adverse effects were not observed in any case. All babies were delivered by cesarean even when FBS was performed. One emergency cesarean was performed for fetal bradycardia after FBS.

Conclusion. This study confirmed that maternal therapy with intravenous immunoglobulin for fetal alloimmune thrombocytopenia gives satisfactory results. It also showed that a less invasive approach, especially a reduction in the number of fetal blood samples, is possible without deleterious consequences. This observation suggests also to start IVIG early during pregnancy and to continue treatment up to delivery.

Keywords:

• Alloimmune thrombocytopenia
• intracranial hemorrhage
• fetal and neonatal thrombocytopenia
• IVIG
• prenatal management

Acknowledgements

Drs. Winer, Mechoulan, Branger, Kaplan and Muller had full access to all of the data in the study and take responsibility for the integrity and the accuracy of the data analysis. Study concept and design: Winer, Muller, Kaplan. Acquisition of data in different centers: Mechoulan, Kaplan, Muller, Philippe, Ville, Oury. Statistical analysis: Branger. Drafting of the manuscript: Mechoulan, Winer. Critical revision of the manuscript for important intellectual content: Kaplan, Winer,Ville. Overall supervision of the study: Winer, Kaplan, Muller. The institutional ethic review board (Groupe Nantais d'ethique dans le domaine de la sante) was consulted (2009-03-03) and determined that its approval was unnecessary since this retrospective study was purely observational. Authors declare that they have no conflict of interest. This study is supported par the French alloimmune study Group and the GROG (Research Group in Obstetrics and Gynecology).