Type 2B von Willebrand Disease in Pregnancy: A Systematic Literature Review.

Our objective was to review the maternal characteristics and obstetric complications in women with type 2B von Willebrand disease (VWD). A systematic literature search was conducted using PubMed, Scopus, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov. We included all publications that addressed type 2B VWD in pregnancy. Our primary and secondary outcomes were incidence of postpartum hemorrhage (PPH) and incidence of thrombocytopenia in pregnancy. Two reviewers independently identified eligible studies and abstracted data including maternal characteristics, hematologic characteristics, treatment, and delivery outcomes. Twenty studies met inclusion criteria. There were 27 women (32 pregnancies) with type 2B VWD. Primary PPH was reported in 9/20 women (45%) and secondary PPH was reported in 6/13 women (46%). Thrombocytopenia in pregnancy was present in 27/28 women (96%); 23/27 women (85%) had platelet count <100 × 109/L, mean 33.7 ± 22.7 × 109/L. Factor concentrate treatment was administered before delivery (n = 16) and postpartum (n = 18), some women received both. Seventeen deliveries required blood products postpartum with 13/17 (76%) platelet transfusions and 6/17 (35%) red blood cell transfusions. No maternal mortality was reported. Women with type 2B VWD have significant morbidity in pregnancy related to high incidence of severe thrombocytopenia and primary and secondary PPH.