Evaluating the risk factors for preeclampsia in subsequent pregnancies in patients with a history of preeclampsia: a single-institution retrospective study.

A history of preeclampsia is the most important risk factor for its development in subsequent pregnancies. However, few studies have focused on the details of previous cases of preeclampsia. This single-institution, retrospective study evaluated the risk of developing preeclampsia in subsequent pregnancies in patients with a history of preeclampsia. Among singleton pregnant women who delivered at our hospital between 2017 and 2021, those who developed hypertensive disorders of pregnancy (HDP) for the first time were recruited. We retrospectively followed patients who had a subsequent pregnancy and delivery at our hospital before 2023 for a recurrence of preeclampsia. Maternal characteristics, time of HDP onset, and mean arterial pressure (MAP) during the first and early second trimester of the subsequent pregnancy were recorded. Of the 7485 deliveries, 413 were first-episode HDP cases, and the outcomes of subsequent pregnancies were noted in 48 patients with initial preeclampsia. Ten patients (21%) had a recurrence of preeclampsia, and those with early onset preeclampsia on the first pregnancy were more likely to have a recurrence (non-recurrent, 4 (11%) vs. recurrent, 5 (50%); p = 0.012). Analysis of the MAP in 40 patients showed higher recurrence rates in patients with elevations in MAP during the early second trimester (ΔMAP (early second - first trimester) median: -6 mmHg vs -3.3 mmHg, p = 0.03). Approximately 20% of patients with initial preeclampsia experience recurrence. The timing of onset in the primary pregnancy is an important predictive factor for preeclampsia in subsequent pregnancies. Changes in MAP may be useful indicators for predicting preeclampsia.