Studies have found that women who consistently take prenatal vitamins before pregnancy have a higher chance of getting pregnant, compared to women who don’t. Last week, we looked at the vitamins that may explain this fertility boost from prenatal vitamins. This week, let’s take a look at the other key group of nutrients: Minerals.
Minerals play key roles in reproductive health
Minerals play multiple roles in our body. Even though the amount of minerals we need each day is minuscule (that’s why they are called “trace” minerals), essential trace elements like zinc, copper, selenium and iodine play key roles in the reproductive processes.
Multiple studies have found that insufficiencies of essential minerals like zinc, selenium and copper are more common among women who undergo IVF. While that trend can’t tell us whether these specific minerals are necessary for fertility (because low levels of these minerals may signal overall poor nutritional status or other cofounding factors), some evidence is emerging, linking healthy mineral levels to normal female fertility.
Minerals with roles in female reproductive health
Zinc, selenium and copper top our list.
1. Zinc may support egg health, ovarian reserve and normal ovulation
As an indispensable mineral for hundreds of enzymatic activities, Zinc is probably at the top of our list. It’s an important mineral during pregnancy that supports the maintenance of the pregnancy, baby’s healthy growth and normal functioning of the placenta. Zinc is also key during the preconception period, with lower maternal levels linked to longer time to conception.
- Zinc drives DNA synthesis, cell division and cell differentiation by modulating the activities of the enzymes necessary for these processes. Since they are central to egg (and sperm) development, fertilization and embryonic growth, scientists think Zinc is a key mineral for reproductive health. Some in vitro studies have also suggested that adding Zinc to the medium where eggs and embryos develop in the lab may improve multiple aspects of egg and embryo quality, such as integrity of the DNA and rate of blastocyst formation. One study even estimated that 9% of infertility may be linked to low zinc intake and/or problems with zinc level regulation in one of the partners.
- While applicabilities to humans are still unclear, some recent studies in animals also suggested that Zinc may influence ovarian reserve from beginning to end; that is to say, from generation of egg cells through follicle development all the way to ovulation.
- According to a 2006 review, Zinc may support normal ovulation, survival of the ovulated egg and regular menstruation, possibly through its antioxidant abilities.
2. Selenium may support luteal phase and healthy egg and sperm
Selenium is an essential mineral with antioxidant capabilities. It’s a component of multiple proteins (called selenoproteins) that drive reproductive processes, thyroid hormone metabolism, DNA synthesis and protection from oxidative damage. Unsurprisingly, Selenium has been suggested as essential to both male and female reproductive health, with normal levels associated with shorter time to pregnancy, higher pregnancy rates and lower risks of miscarriages.d
- A healthy level of Selenium may support luteal phase – the part of your menstrual cycle after ovulation when the lining of the uterus thickens to prepare for a possible pregnancy. For example, a small 2015 study evaluating the diet of 259 healthy women and their cycles found a positive relationship between healthy Selenium intake levels and normal luteal phase length.
- Selenium may be essential to the health of sperm, eggs and embryos. A 2020 study conducted with 103 couples undergoing IVF found that women with a healthy serum level of Selenium in the blood had higher rate of embryos reaching the blastocyst stage. A similar relationship was observed among men, between Selenium levels in the seminal fluid and pregnancy/live birth rates. As authors note, not all results from similar studies line up, and the relationship between Selenium levels and positive outcomes are not always linear. More studies are needed to understand the mechanisms.
3. Copper may support the development of endometrium, placenta and embryos
Given that copper IUD is a common method of contraception, it might seem strange to see copper on the list of minerals that may have a supportive role in reproductive processes. However, analyses of fertility patients like this one have found that women who seek fertility treatment tend to have lower levels of copper than their healthy counterparts.
Animal studies have also suggested that an adequate level of copper may be essential to fertility for both men and women. This may be due to copper’s versatile roles in many physiological processes, including angiogenesis (formation of new blood cells, which is essential for placental development), regulation of gene expression and defense against oxidative damage for the corpus luteum and for the developing embryo.
Bottom line on prenatal minerals for fertility
The bottom line on prenatal minerals and fertility is this: Start on a good prenatal vitamin and mineral supplement early, and stay on it.
Aside from zinc, selenium and copper, make sure your prenatal multi contains these other fertility-supporting minerals:
- Calcium. Copper may help our body maintain a healthy level of Vitamin D, which in turn appears to support reproductive and prenatal health. Direct effects of calcium on fertility are still being studied, but it's a key mineral for mom's health and the baby's development once you are pregnant.
- Iron. Iron is necessary to grow new red blood cells and has been suggested as necessary for the maintenance of early pregnancies and supportive of normal ovulation.
- Iodine. Iodine is a component of thyroid hormones, which touch practically every aspect of female reproductive processes, from production of reproductive hormones, egg maturation, endometrial development and regulation of ovulatory cycles.
For a more in-depth look at how women's health experts choose prenatal vitamins, check out this "How to Choose a Prenatal" webinar with Dr. Stephanie Nichols - and please reach out if you have any questions. We are with you.
