573: Abnormal second trimester serum analytes are more predictive of earlier and more severe variants of preeclampsia than mild preeclampsia

more predictive of earlier and more severe variants of preeclampsia than mild preeclampsia Richelle Olsen, Douglas Woelkers, Andrew Hull, Yvette LaCoursiere UCSD Medical Center, Department of Reproductive Medicine, San Diego, CA, University of California San Diego, Department of Reproductive Medicine, San Diego, CA OBJECTIVE: To determine the relative association of abnormal second trimester serum analytes with mild versus severe forms of preeclampsia-toxemia (PET) STUDY DESIGN: This is a retrospective cohort study of 7767 subjects undergoing second trimester serum aneuploidy screening from a single institution. Values of maternal serum alpha fetoprotein (AFP), beta hCG (HCG) and inhibin (INH) were independently calculated as gestational age specific multiples of the median (MoM) for each subject. Outcomes evaluated were gestational age at delivery and occurrence and severity of PET. Cases were classified as having preeclampsia with delivery 34 weeks ( 34 PET), preeclampsia with delivery 34 weeks ( 34 PET), or mild and severe preeclampsia (mPET and sPET) by usual clinical criteria (ACOG 1996, 2002). Results were analyzed using Students t-test, chi square and stepwise logistic regression. RESULTS: In this cohort, there were 459 (6.5%) cases of preeclampsia, of whom 65 (14%) delivered prior to 34 weeks and of whom 394 (86%) delivered after 34 weeks. Elevated concentrations of AFP, HCG and INH were significantly associated with the occurrence of any form of PET. For each abnormal analyte 2.0 MoM, the odds ratio was higher for the development of 34 PET (see Table 1). This association remained when comparing mPET and sPET. The higher the MoMs for each analyte the greater the likelihood of PET and the more likely that the PET would be severe. CONCLUSION: Elevated concentrations of AFP, HCG, and INH are more strongly predictive of severe and early variants of preeclampsia than of mild disease at term, and this risk differential increases as the concentration of the analytes rises. This information may help stratify women at higher risk for adverse outcomes who require more vigilant monitoring.