Between 15 to 20% of all couples will experience one or more periods of involuntary infertility. This means that you try in vain to get pregnant for more than a year. 

But both men and women can increase their fertility themselves with the help of lifestyle changes and diet. You can read more about that in the article here. And there are also several nutritional supplements that can positively affect the fertility of both men and women. You can read more about which nutritional supplements can increase male fertility in the article here

What supplements can help increase female fertility? 


Lack of zinc can damage fertility and have a long-term effect on the development of the woman's eggs. Zinc is important for the development of eggs in the woman's ovaries. This is because zinc deficiency impairs the possibility that the eggs at ovulation can be fertilized and divide as they should, if it is to develop into pregnancy. This is shown by several experiments from, among others, the United States


A woman's follicles, which are the cells that help mature a woman's eggs, can be adversely affected if she is deficient in selenium. Therefore, it is important that she gets the recommended amount of selenium daily of 40 micrograms to ensure that she has well-functioning follicles and produces fertile eggs.

When the woman becomes pregnant, selenium also plays an important role for the fetus in relation to, for example, preventing premature birth. According to a Dutch-British study of 1,000 women in their 12th week of pregnancy, researchers found that women with the lowest levels of selenium in their blood were twice as likely to give birth prematurely compared to those with higher levels. At the same time, there was an increased risk of pregnancy-related hypertension and preeclampsia in women with low levels of selenium in the blood. 

D vitamin

A study from 2019 showed that a lack of vitamin D is very common in the group of women who experience reduced fertility. In the study, 500 infertile women were examined, and here it turned out that 84% of them had a lack of vitamin D. A number that is significantly above the average woman of reproductive age.

In connection with fertility treatment, a number of studies have shown that women with a normal level of vitamin D in the blood (above 30 ng/mL or higher) have a better chance of achieving pregnancy and later avoiding miscarriage. The reason is thought to be that vitamin D affects the mucosa's receptivity to a fertilized egg. Several Danish fertility clinics therefore recommend that women undergoing fertility treatment have their vitamin D measured before starting fertility treatment. However, it is important to emphasize that no large-scale research studies and lottery trials have been carried out. Therefore, it cannot be concluded with certainty that women with vitamin D deficiency have improved fertility with vitamin D supplementation.

Which nutritional supplements are recommended for pregnant women?

The Danish Health Authority recommends that pregnant women take the following nutritional supplements:

Folic acid 

Here the recommendation is to consume 400 micrograms (µg) of folic acid daily from the time you plan pregnancy (preferably 3 months before pregnancy) and continue to take it every day until you are 12 weeks into the pregnancy

D vitamin

Many Danes have too low a level of vitamin D in their blood, and since vitamin D promotes the absorption of calcium and strengthens the bone structure, it is an important dietary supplement for both the pregnant woman and the unborn child. The Danish Health Authority recommends a daily supplement of 10 micrograms of vitamin D throughout pregnancy.


Research has shown that approximately one in five pregnant women develops iron deficiency late in pregnancy, if not, you take a daily iron supplement. The recommendation is 40-50 mg of iron from the 10th week of pregnancy and then for the rest of the pregnancy.


Calcium is important both for the pregnant woman but also for the bones of the unborn child. The Danish Health Authority recommends that pregnant women either eat or drink 0.5 liters of milk product per day or take a daily iron supplement of 500 mg throughout pregnancy