Gestational Thrombocytopenia: A Case-Control Study Of Over 3,500 Pregnancies

Gestational thrombocytopenia (GT) affects an estimated nine million women annually. Women with GT have recurrent episodes on subsequent pregnancies suggesting that GT is related to a maternal factor rather than a factor unique to the individual pregnancy. We performed a case-control study of over 3 500 pregnancies at a single hospital during 2017. We defined GT as any pregnancy with a platelet count versus 208 000/mu l in controls, P < 0 center dot 0001. During the pregnancy, the platelet count declined 31 center dot 8% in cases compared with 18 center dot 3% in controls (P < 0 center dot 0001) in association with a significant increase in mean platelet volume during each trimester. Among women with GT, platelet counts rapidly increased during the first week postpartum, consistent with a mechanism directly related to high blood flow rates in the gravid uterus. GT, a recurrent condition of at-risk women, is a common haematological disorder of pregnancy. Future research may focus on genetic gain-of-function polymorphisms resulting in increased turnover of platelets uncovered only during periods of high-shear blood flow.