Poster Session 4
Category: Hypertension
Poster Session 4
.jpg "Ji Yeon Lee, MD, PhD (she/her/hers) photo")
Ji Yeon Lee, MD, PhD (she/her/hers)
Associate professor
CHA Bundang Medical Center, CHA University School of Medicine
CHA Bundang Medical Center, CHA University School of Medicine / Seongnam, Kyonggi-do, Republic of Korea
Hee Young Cho, MD, PhD (she/her/hers)
Professor
Obstetrics and Gynecology, Seoul National University College of Medicine
Seoul, Kyonggi-do, Republic of Korea
Nari Kim, MD
CHA Bundang Medical Center, CHA University School of Medicine
CHA Bundang Medical Center / Seongnam, Kyonggi-do, Republic of Korea
Hyun Mee Ryu, MD, PhD
CHA Bundang Medical Center, CHA University School of Medicine
CHA Bundang Medical Center/ Seongnam, Kyonggi-do, Republic of Korea
Preeclampsia is thought to originate from abnormal placentation during implantation. Initiating low-dose aspirin closer to this window may improve its preventive effect. Current guidelines recommend starting aspirin at 12 weeks due to limited data supporting earlier use. This study aimed to assess whether starting low-dose aspirin before 12 weeks improves maternal and neonatal outcomes compared to starting between 12–20 weeks in women with multiple moderate-risk factors for preeclampsia.
Study Design:
This retrospective cohort study included singleton pregnancies between 2012 and 2025. Eligible women had ≥2 moderate-risk factors for preeclampsia and were prescribed daily low-dose aspirin, delivering at ≥20 weeks at our hospital. Women with high-risk factors (e.g., prior preeclampsia, multifetal gestation, chronic hypertension, diabetes, renal or autoimmune disease) were excluded. Subjects were grouped by aspirin initiation timing: early (< 12 weeks, n=1,802) vs. late (12–20 weeks, n=473). Multivariate analyses adjusted for maternal characteristics.
Results:
The early group had higher rates of nulliparity (77.0% vs. 66.0%) and IVF (77.4% vs. 39.1%). Compared to the late group, the early group had lower adjusted risks for gestational hypertension (aOR 0.33, 95% CI 0.21–0.52), preeclampsia (aOR 0.30, 95% CI 0.17–0.54), gestational diabetes (aOR 0.57, 95% CI 0.40–0.80), and preterm birth < 32 weeks (aOR 0.04, 95% CI 0.01–0.10). Neonatal outcomes were also improved: lower risks of 5-min Apgar < 7 (aOR 0.26, 95% CI 0.12–0.55), NICU admission (aOR 0.52, 95% CI 0.40–0.66), bronchopulmonary dysplasia (aOR 0.08, 95% CI 0.02–0.30), jaundice (aOR 0.68, 95% CI 0.53–0.87), patent ductus arteriosus (aOR 0.35, 95% CI 0.22–0.57), and retinopathy of prematurity (aOR 0.41, 95% CI 0.27–0.63).
Conclusion:
Starting aspirin before 12 weeks in moderate-risk pregnancies significantly reduced adverse maternal and neonatal outcomes. These results support revising guidelines to align aspirin use with the timing of placentation.