Maternal Vascular Adaptation in High-Risk Pregnancies: Effects of Early Smoking Cessation on Hemodynamic and Endothelial Function

Cardiovascular adaptation is vital for a healthy pregnancy but may be impaired in women at high risk for preeclampsia (PE), a condition marked by endothelial dysfunction. Smoking may lower the PE risk but harms vessels, and the effects of early cessation remain unclear. This prospective cohort study assessed vascular changes in high-risk pregnancies and the potential influence of early smoking cessation. Of 110 women screened for PE in the first trimester, 43 were classified as high-risk: 18 former smokers and 25 lifelong non-smokers. Vascular assessments were performed at 11-16, 24-28, and 34-37 weeks of gestation. Parameters included the carotid-femoral pulse wave velocity (cfPWV), asymmetric dimethylarginine (ADMA), mean arterial pressure (MAP), systolic and diastolic blood pressure (SBP, DBP), heart rate (HR), and retinal vessel calibers (central retinal arteriolar and venular equivalents (CRAE, CRVE)). Serum cotinine confirmed abstinence in former smokers. Across gestation, ADMA (<i>p</i> = 0.034), MAP (<i>p</i> = 0.001), SBP (<i>p</i> = 0.033), DBP (<i>p</i> = 0.004), and HR (<i>p</i> = 0.004) increased, while CRAE (<i>p</i> = 0.016) and CRVE (<i>p</i> = 0.004) narrowed in late pregnancy; cfPWV remained stable (<i>p</i> = 0.783). Non-smokers showed increases in their ADMA (<i>p</i> = 0.020), MAP (<i>p</i> = 0.001), and DBP (<i>p</i> = 0.0001) with no differences between groups. High-risk pregnancies showed vascular changes with similar profiles in former and non-smokers, underscoring the need for broader studies.