High altitude alters maternal-fetal adaptation in preeclampsia pregnancies.

Combined preeclampsia and FGR show distinct features at high altitude.

Population-based findings highlight risks in high-altitude pregnancies.

Placental dysfunction under hypoxia links preeclampsia and fetal growth issues.

Geographic altitude is a key factor in hypertensive disorders of pregnancy.

Preeclampsia (PE) and fetal growth restriction (FGR) are major contributors to maternal and neonatal morbidity and mortality globally. The pathophysiology of these conditions is further complicated by high-altitude (HA) environments due to hypoxia-induced changes in maternal and fetal physiology. This study aimed to evaluate the maternal and neonatal outcomes of PE, with and without FGR, in a HA setting (Bogotá, Colombia, 2,640 m.a.s.l.).

This retrospective, cross-sectional study analyzed 437 patients diagnosed with PE between 2020 and 2023. Participants were stratified into groups with and without FGR based on established diagnostic criteria. Data were collected from electronic medical records. Variables included maternal clinical features, neonatal outcomes, and severity of PE manifestations.

Among patients diagnosed with PE, 18.76% also met diagnostic criteria for FGR. Compared with patients with PE alone, those with PE and FGR presented at an earlier gestational age (median 33.1 weeks [30.2–36.2] vs. 36.6 weeks [34.4–38.4], p < 0.001). Neonatal outcomes were significantly worse in the PE + FGR group, including lower birth weight (1,655 g vs. 2,700 g, p < 0.001), higher NICU admission rates (87.0% vs. 65.6%, p < 0.001), and increased early neonatal mortality (7.32% vs. 1.13%, p = 0.001). Although differences in maternal severe features did not reach statistical significance, a consistent trend toward greater hepatic and hematologic involvement was observed among patients with concomitant FGR. Additionally, patients with PE and FGR more frequently required outpatient antihypertensive therapy after discharge, including a greater need for multiple agents (p = 0.002).

HA is a factor that may influence the clinical behavior of PE and FGR, with important implications for both maternal and neonatal outcomes. These findings underscore the need for tailored clinical protocols for populations living at HA and highlight the relevance of further research into the genetic and physiological adaptive mechanisms involved. Future studies should explore longitudinal outcomes and investigate potential biomarkers to improve risk stratification and guide management strategies specific to HA settings.

Preeclampsia

Fetal growth restriction

High altitude

Outcomes

© 2026 The Author(s). Published by Elsevier B.V. on behalf of International Society for the Study of Hypertension in Pregnancy.