All cases that were coded as preeclampsia in the hospital data-
bases were individually assessed by the senior author to ensure
that the criteria for preeclampsia, as described below, were satis-
fied.
Data recorded included maternal age, gestation week at diagnosis, gravidity, parity, previous preeclampsia, blood pressure, proteinuria, gestation weeks at delivery, birth weight, stillbirth
and umbilical artery systolic velocity/diastolic velocity (S/D) ratio.