Perinatal outcome in pregnant women: the impact of blood transfusion.

Abstract

Background: Obstetric hemorrhage is a life-threatening complication of pregnancy. Systematic collection of data on transfusion practice during pregnancy and post-partum period are scarce, as well as data on fetal or neonatal outcomes of women transfused during pregnancy.We examined the prevalence of obstetric hemorrhage and outcome of pregnancies in hospitalized transfused women.

Materials and methods: This is a retrospective cohort study collecting clinical and laboratory data of women transfused from 2015 to 2017 in three Italian Tertiary level Obstetrical Departments. Inclusion criteria were: 1) age >18 years; 2) antepartum or peripartum hospital admission and 3) transfusion during the hospital stay of at least one unit of packed red blood cell (RBC) units. Women below 18 years and/or with transfusion outside pregnancy were excluded.During the observation period, 18,495 women gave birth across the three Obstetrics Departments: transfusion rate was 1.7%.

Results: 315 women were included in the final analysis. Most (75.2%) needed transfusion from 35 weeks onwards. A percentage higher that that observed in general population of transfused women showed co-morbidities such as hypertensive disorders or diabetes (13.9 vs 5.5%). We recorded 90% of live births and 7.6% of Intra Uterine Fetal Demise or neonatal death. Perinatal outcomes were impacted by the dose of transfusion: logistic regression, correcting for age and assisted conception, showed that women transfused with 3 or more RBC units have about 3-fold higher risk of perinatal death (OR: 2.9, 95% CI: 1.0-8.4).

Discussion: In this series, several known risk factors were associated with adverse feto-neonatal outcome. In addition, the number of RBC units transfused was significantly and independently associated with the perinatal outcome. Present data can be helpful to design prospective studies taking into account timing and dose of transfusion during pregnancy with the objective to improve feto-maternal outcome.