A healthy pregnancy. Selenium is an essential trace element needed to support a healthy pregnancy. However, to date, studies of the mother’s selenium status and the child’s growth and development are scarce. Data from the Odense Child Cohort study in Denmark give researchers an opportunity to investigate the possible effects of the mother’s low selenium intake and low selenium status on the child’s neuro-development [Demircan 2023; Demircan 2024].
Selenium Supplementation and Preeclampsia Risk
Selenium supplementation of pregnant women at a high risk of preeclampsia has shown beneficial effects on 1) serum selenium levels, 2) some metabolic profiles, 3) uterine artery pulsatility index, and 4) mental health, compared to placebo. The study compared the effect in 60 pregnant women of supplementation with 200 mcg/day for 12 weeks with the effect of placebo for the same period.
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The supplementation took place for 12 weeks starting in weeks 16 to 18 of pregnancy. No side effects related to the intake of 200 mcg of selenium per day by pregnant women at high risk of preeclampsia were reported throughout the duration of the study [Mesdaghinia 2022].
Selenium Supplementation Compared to Placebo
How did the selenium supplementation compare with the placebo supplementation in the pregnant women?
Low Selenium Status and At-Risk Pregnancies
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A recent review article presents the evidence that low selenium status in pregnant women may be implicated in the following complications [Duntas 2020]:
- miscarriage
- preeclampsia
- pre-term birth
- retarded fetus intrauterine growth
- post-partum hypothyroidism and auto-immune thyroiditis
To ensure an optimal pregnancy outcome, Dr. Leonidas Duntas recommends that physicians take an individualized approach and prescribe dietary and supplemental selenium intakes that are tailored to the pregnant woman’s needs.
Why is Adequate Selenium Important for Pregnant Women?
Selenium is an essential trace element. Its intake and status in the blood plasma can vary considerably according to a number of factors [Duntas 2020]:
- differences in diet and nutrition
- differences in soil and plant selenium content
- ethnic differences
- genetic differences
Without a blood selenium test, it is not possible to know whether women planning a pregnancy have sufficient circulating selenium. The Mayo Clinic reports that the normal selenium concentration in adult human blood serum in the United States is 70 to 150 micrograms per liter with a population mean value of 98 micrograms per liter.
Selenium Supplementation and Polycystic Ovary Syndrome (PCOS)
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Polycystic ovary syndrome (abbreviated PCOS) is a hormonal disorder with a prevalence of 5 – 10% in women of reproductive age.
- The exact cause of PCOS is unknown.
- Symptoms of PCOS include irregular periods, increased levels of male hormone, and failure of the ovaries to function regularly.
- Excess insulin production and low-grade inflammation are thought to have an effect on the development of PCOS [Mayo Clinic].
Selenium: Effect on Mental Health, Hormonal Profile, Inflammation, and Oxidative Stress in Patients with PCOS
In a randomized controlled trial enrolling 60 women aged 18 – 40 years, daily co-administration of a probiotic supplement and 200 micrograms of selenium for 12 weeks was associated with the following outcomes [Jamilian 2018]:
- significant improvement in Beck Depression Inventory scores, general health questionnaire scores, and depression anxiety and stress scale scores compared with the placebo
- significantly reduced total testosterone levels, hirsutism, high-sensitivity C-reactive protein levels (a bio-marker for inflammation), and malondialdehyde levels (a bio-marker for oxidative stress) as well as significantly increased total antioxidant capacity and total glutathione (GSH) levels compared with the placebo
The researchers concluded that the co-administration of probiotics and selenium for 12 weeks to women with PCOS had beneficial health effects.
Selenium: Effect on Metabolic Profile in Patients with PCOS
In a randomized controlled trial enrolling 70 women aged 18 – 40 years, daily supplementation with 200 micrograms of selenium for 8 weeks was associated with the following outcomes compared with placebo [Jamilian 2015]: