RISK OF PREECLAMPSIA IN 2ND-TRIMESTER TRIPLOID PREGNANCIES

Objective: To determine the magnitude of the risk and the predictive c linical characteristics for development of preeclampsia when triploidy is diagnosed in the second trimester. Methods: A retrospective analys is of databases maintained by the cytogenetics laboratories at the Uni versity of Iowa and University of North Carolina was performed to iden tify all cases of triploidy. We examined the karyotype, maternal serum screening (particularly the hCG level), ultrasound results, and evide nce of maternal hypertensive disease. Results: Seventeen cases of trip loidy were identified between 1987 and 1996. Preeclampsia or hypertens ion complicated six of these cases with onset between 15 and 22.5 week s' gestation. In these six cases, the serum hCG level was extremely hi gh. Serum screening results were available in seven cases in which pre eclampsia did not develop, and the hCG levels were under 0.09 multiple s of the median in five of the seven cases. In all six cases in which preeclampsia or hypertension developed, there was sonographic evidence of placentomegaly. Sonographic findings in 16 of 17 cases revealed fe tal growth restriction, oligohydramnios, fetal anomalies, placentomega ly, or a combination of these. Conclusion: In our series of pregnancie s complicated by triploidy, the risk of developing preeclampsia or hyp ertension in the second trimester was 3570. It appears that elevated s erum hCG levels and placentomegaly are associated with a higher risk o f preeclampsia but low hCG levels are not. This information is importa nt in counseling patients who are hesitant to terminate a pregnancy pu rely for a fetal abnormality, even if the anomaly is lethal. (C) 1997 by The American College of Obstetricians and Gynecologists.