The impact of pre-pregnant obesity on the maternal hemodynamics in early pregnancy

Abstract

Maternal obesity is associated with a substantial risk of complications during pregnancy. Furthermore, it also impacts maternal cardiovascular adaptation, leading to cardiovascular disease later in life. This study aims to investigate the hemodynamic impact of obesity in the first trimester using USCOM® (Ultrasound Cardiac Output Monitor), a non-invasive and quantitative method. A prospective observational study of women with singleton pregnancy enrolled in prenatal care at a University of Miami clinic between January 2022 and July 2022. Pregnant women with a history of preexisting severe cardiorespiratory disease or congenital heart defect affecting cardiac function and taking Aspirin were excluded. Comprehensive cardiovascular parameters via USCOM® were obtained. Patients were divided into three subgroups: normal weight, overweight, and obesity according to pre-pregnancy BMI. Data were analyzed by one-way ANOVA with post hoc Bonferroni test for continuous parametric data, Kruskal-Wallis test for non-parametric data, and Pearson chi-square test for categorical data. P < .05 was considered statistically significant. Doppler waveforms for analysis were achieved for 48 women among 57 participants. Gestational age at inclusion, maternal age, ethnicity, race, blood pressure, history of preeclampsia, and preexisting chronic hypertension was not significantly different between groups. Maternal cardiovascular changes were identified in group 3. Compared to women with normal weight, obese women had significantly elevated Ejection Time Percentage (ET%) and Flow Time Corrected (FTc), and significantly reduced Stroke Volume Index(SVI), Cardiac Index(CI), and Inotropy Index(II). However, Stroke Volume (SV), Cardiac Output (CO), systemic vascular resistance (SVR), and Peak Velocity (PV) are not significantly different between groups. Our study shows that maternal hemodynamics is significantly altered in obese pregnant women from the first trimester and is characterized by high preload, low afterload, and reduced cardiac function.View Large Image Figure ViewerDownload Hi-res image Download (PPT)