Distinct Gestational Blood Pressure Trajectories Predict Pregnancy, Birth, and Postpartum Health in a Low-Income Hispanic Population

Objective: Blood pressure (BP) typically drops to a nadir around 20 to 24 gestation weeks in a normal pregnancy. Distinct BP trajectories over pregnancy could reveal underlying cardiovascular function and predict future cardiovascular risk, but little is known about BP trajectories in Hispanic women. We aim to identify BP trajectories during pregnancy among low-income, Hispanic women. Methods: In the prospective Maternal and Developmental Risks from Environmental and Social Stressors (MADRES) pregnancy cohort, we abstracted clinic BP measures of 732 participants who had an average of 12 BP measures over pregnancy, ranging from 4 to 41 weeks. We used latent class mixture modeling to identify BP trajectories. We examined associations of population characteristics, pregnancy and birth outcomes, and 1-year postpartum BP with the identified trajectories. Results: We identified three distinct BP trajectories ( Figure ). Compared to the majority (class 1, n=569), the consistently high class 2 (14.8%, 108) was characterized by a higher pre-pregnancy BMI (ppBMI, 32.3±7.6 vs. 27.6 ±6.1 Kg/m 2 ) and a higher proportion of having college or above education (21.3% vs. 14.9%), while the high-low-high U-shape class 3 (7.5%, 55) had a higher ppBMI (32.0±7.9 Kg/m 2 ) but lower proportion of having college or above education (9.1%). Risk of preeclampsia was the highest in class 3 (43.6%), followed by class 2 (10.2%) and class 1 (6.0%), while the risk of gestational diabetes was the highest in class 2 (14.8%), followed by class 1 (7.9%) and class 3 (7.3%). Birthweight and gestational duration were both significantly lower in class 3 than classes 1 and 2. One-year postpartum systolic BP was significantly higher in class 2 (120.2±16.0 mmHg) and class 3 (122.4±16.0 mmHg) than class 1 (111.7±26.2 mmHg) after adjusting for maternal age, pre-pregnancy BMI, parity, and education. Conclusion: Elevated blood pressure may develop into district trajectories in pregnancy that further predict pregnancy and birth outcomes, as well as postpartum blood pressure.