O29. The impact of low dose aspirin after positive first trimester screening for pre-eclampsia

Abstract

Introduction Pre-eclampsia is a major cause of maternal and perinatal morbidity and mortality. The prophylactic use of low dose aspirin (50–150mg/day) is associated with a reduction in the incidence or severity of pre-eclampsia between 50–90% if the treatment begins before the 16th week of gestation. Promising multifactorial screening models in first trimester of pregnancy are in use to predict pre-eclampsia, especially early onset disease before the 34th week of gestation. Objectives Combining this issues we conducted an observational study and evaluated the outcome of women on low dose aspirin after a positive first trimester screening test for pre-eclampsia based on two different risk calculations models. Methods We have completed outcome data of 401 women with performed multifactorial screening test for pre-eclampsia at 12–14 weeks of gestation in a clinical setting, from June 2012 until September 2014 using two different risk-calculation software. In the first time period until October 2013 we used the Pre-eclampsia Predictor™ Software by PerkinElmer (group PE). Thereafter the prediction algorithm in Viewpoint® (group VP) was used to calculate the risk for pre-eclampsia. Women who were screened positive for the development of early and late onset of pre-eclampsia (early: 34th week of gestation e.g. late > 34th week of gestation) in the group PE and for early onset pre-eclampsia ( 34th week of gestation) in the group VP were prescribed low dose aspirin (75–100mg/day) starting before 16 gestational weeks and until 34 completed weeks of gestation. Descriptive and explorative statistical analyses were performed. A two-sided p -value of less than 0.05 was considered as significant. Results There were 214 women in the PE group and 187 in the VP group. In the PE group 17 (7.9%) women were screened positive for early onset pre-eclampsia and 46 (21.5%) for late onset pre-eclampsia. In the VP group 44 (23.5 %) were screened positive for early onset pre-eclampsia. Regarding screening positive for early onset pre-eclampsia groups differ significant ( p =0.000). Comparing prescription of low dose aspirin and outcome of pre-eclampsia (4 (1.8%) cases in the PE and 5 (2,7%) cases in the VP group) there were no significant differences between the two groups. There were no cases of early onset or severe form of pre-eclampsia in both groups. Conclusion The both used predication algorithms are not similar but were similarly applied so that the outcomes of women were not different. Using a multifactorial first trimester screening test with subsequent administration of low dose aspirin in a screening-positive group of pregnant women is a promising strategy to reduce early onset and severe forms of pre-eclampsia, but cut offs of algorithms should be improved.