There is a clear relationship between a pregnant woman’s selenium status and her risk of pre-eclampsia. Observational studies show that low selenium status is associated with a greater risk of pre-eclampsia. Studies of selenium supplementation have shown reduced incidence of pre-eclampsia [Xu].
What is pre-eclampsia?
Pre-eclampsia is a complex condition characterized by the onset, around week 20 of the pregnancy, of the following symptoms:
- abnormally high protein levels in the urine (indicating possible damage to the kidneys)
- systolic blood pressure greater than 140 mmHg or diastolic blood pressure greater than 90 mmHg when measured twice with an interval of at least 4–6 hours and not more than 7 days apart [Uzan]
- severe headaches
- blurred vision
- decreased platelet levels in the blood [Mayo Clinic]
Pre-eclampsia seems to be caused by an abnormal development of the new blood vessels that are needed to carry blood to the placenta. The new blood vessels are narrower than they should be, and they respond differently to hormonal signaling [Mayo Clinic].