Healthy fertility and pregnancy require sufficient selenium

Lack of selenium increases the risk of impaired fertility and complications in connection with pregnancy and birth. Because selenium deficiencies are rather common, both men and women should ideally make sure that they get enough of this essential trace element that is involved in various functions - right from conception to delivery.

All cells contain selenium, and it is hardly a coincidence that the largest concentrations are found in the sex glands and sperm cells. Lack of selenium impairs fertility in both humans and animals. In fact, farmers have supplemented their livestock with selenium for decades as a way of preventing fertility problems and miscarriages. After all, good animal health is important for the economy. Because we humans feed off the same selenium-deprived food chain as animals, we should most certainly also pay attention to this vital nutrient, especially childless couples and pregnant women.

Approximately one in seven couples is childless, and for many women it is a race against time with their biological clock ticking louder and louder. Evidence suggests that selenium supplements may be useful on nature's own premises and perhaps even render expensive and unpleasant fertility therapies obsolete

Slow metabolism is common and may have serious complications

A study published in the journal The Obstetrician & Gynaecologist links female infertility to metabolic disorders, which thousands of women suffer from - often without knowing it.
Slow metabolism (hypothyroidism) and its early stage known as subclinical hypothyroidism may have serious complications in connection with pregnancy and childbirth. Not only can slow metabolism make it difficult to become pregnant, it can even increase the risk of miscarriage, preeclampsia, premature delivery, low birthweight, and stillbirth.

The thyroid gland and metabolism are unable to function with selenium

The thyroid gland produces thyroid hormones that channel oxygen into the cells to help them convert (oxidize) food into energy. Iodine is involved in the thyroid hormones T4 (with 4 iodine atoms) and T3 (with 3 iodine atoms). However, selenium-containing enzymes are also needed to remove a single iodine atom from the passive T4 hormone, thereby converting it to the active T3 hormone. Lack of selenium impairs the body's ability to activate its thyroid hormones, causing the metabolism to slow down. Slow metabolism is often insidious. A selenium deficiency also makes it difficult for the body to utilize metabolic drugs like Eltroxin that contain the passive T4 hormone.
In any case, it is highly important that the metabolism functions well and is properly regulated during pregnancy and birth.

Selenium deficiency increases the risk of complications and premature delivery

10-20% of pregnant women are at risk of premature delivery due to a ruptured fetal membrane. A Dutch-British study of 1,000 women in their 12th week of pregnancy showed that those women who had the lowest selenium levels in their blood were twice as likely to give premature birth as those with the highest selenium levels. Also, they had an increased risk of pregnancy-induced hypertension and preeclampsia.

Preconceptual selenium supplementation for safer pregnancy and birth

 The study also shows that pregnant study participants who were given supplements of selenium yeast had a lower rate of preeclampsia, which is the leading cause of premature delivery. Preeclampsia may even lead to life-threatening conditions such as eclampsia.
There is a lot of evidence suggesting that selenium has a constructive and protective role in pregnancy. Researchers point to cardiovascular effects in the placenta as a sign that selenium functions as a powerful antioxidant and counteracts inflammation.

Selenium supplementation increases levels of progesterone

A woman's ability to conceive gradually decreases from her 35th year, mainly because the quality of her eggs decreases but also because she produces less progesterone in her corpus luteum (yellow body) after ovulation. One of progesterone's roles is to maintain the pregnancy after successful conception. Partial lack of progesterone is a common cause of PMS and reduced fertility after the age of 35, even in situations where the menstrual periods remain normal.
A study has shown that selenium supplementation of cows may increase progesterone levels in plasma. The scientists assume that selenium contributes to increasing the production of progesterone in corpus luteum, and this may even be the case in humans, as well.

Sexually active men need more selenium

Recent studies show that in around half the cases where couples are unable to conceive, the men have poor sperm quality. The sperm cells race towards the egg to fertilize it, and in order to fuel the tail-wagging action they need certain selenium-containing proteins in their tailpiece. Selenium also functions as an antioxidant that protects the sperm cell's DNA. A selenium deficiency makes the sperm cells vulnerable to something called DNA fragmentation. The result of this may be that even if a sperm cell successfully fertilizes an egg, the egg will not be able to develop and is therefore rejected by the body.
Selenium stimulates the production of healthy sperm cells and protects their genetic coding. For that reason, sexually active men need more selenium, as the nutrient is used in every single ejaculation.

Compensating for the declining selenium intake

Selenium is found in fish, Brazil nuts, organ meat, meat, and whole-grain. The European agricultural soil, however, is low in selenium, and therefore the average diet is only able to provide around 40-50 micrograms of selenium per day. This is further complicated by the fact that pregnant women are advised to limit their intake (or avoid completely) organ meat and fish, especially predatory fish, which are good selenium sources.
Based on the above mentioned studies, women who are pregnant or plan to become pregnant are likely to benefit from taking a daily supplement (100 micrograms) of organic selenium. Supplements based on selenium yeast are the best choice, as they have better absorption and provide a wide array of different selenium compounds similar to the variety found in a selenium-rich diet.

References:

Jefferys Amanda et al. Thyroid dysfunction and reproductive health. The Obstetrician & Gynaecologist. 2015

Hilten T Mistry et al. Selenium in reproductive health. Journal of Obstetrics and Gynaecology. 2011

Fatemeh Tara et al. Selenium Supplementation and the Incidence of Preeclampsia in Pregnant Iranian Women: A Randomized, Double-Blind, Placebo-Controlled Pilot Trial. Taiwanese Journal of Obstetrics and Gynecology. 2010

Fatemeh Tara et al. Selenium supplementation and premature (pre-labor) rupture of membranes: a randomized double-blind placebo-controlled trial. Journal of Obstetrics and Gynaecology. 2010

Kamada H, Hodate K. Effect of dietary selenium supplementation on the plasma progesterone concentration in cows. Journal of Veterinary Science 1998

Christensen BT et al. Selenanvendelse i dansk landbrug. Rapport fra DJF 2006. Videncentret for landbrug.

Drutel, A et al: Selenium and the thyroid gland: more good news for clinicians. Clinical Endocrinology. 2013.