Selenium and maternal blood pressure during childbirth

Area of Science:

• Environmental Health
• Cardiovascular Health
• Trace Element Metabolism

Background:

• Selenium's role in cardiovascular health is complex, with evidence suggesting adverse effects at concentrations outside the nutritional range.
• Maternal exposure to environmental factors can influence pregnancy outcomes, including blood pressure.

Purpose of the Study:

• To investigate the association between maternal selenium exposure and blood pressure (BP) during pregnancy.
• To explore the potential dual role of selenium as both an essential nutrient and a toxicant in relation to maternal cardiovascular health.

Main Methods:

• Umbilical cord serum selenium concentrations were used as a proxy for maternal exposure in 270 deliveries.
• Multivariable linear spline models controlled for covariates like gestational age, maternal age, and BMI.
• Non-parametric analysis identified spline knots for selenium at 70 and 90 μg/l.

Main Results:

• A potential u-shaped relationship was observed between selenium levels and maternal BP.
• For selenium concentrations between 70-90 μg/l, a 1 μg/l increase was associated with a significant increase in both systolic (0.37 mm Hg) and diastolic (0.35 mm Hg) BP.
• No statistically significant decrease in BP was observed with increasing selenium levels below 70 μg/l.

Conclusions:

• Maternal selenium exposure may have a non-linear effect on blood pressure, with potential adverse impacts at higher concentrations.
• The findings support a dual role for selenium, acting as an essential micronutrient but also a potential toxicant at elevated levels.
• Further research is warranted to fully elucidate the complex relationship between selenium and maternal cardiovascular health.