Should pregnant women eat for two*? When it comes to preventing iron deficiency, the answer is a resounding yes. This is because during this particular phase of life, the maternal iron requirement doubles, increasing the risk of iron deficiency. Here you can find out which symptoms make a timely medical clarification advisable, a what point the term iron deficiency is used and much more.
* These days, this old wives’ tale is deemed to be totally outdated from a scientific point of view. Pregnant women should not eat twice as much, but rather twice as well.
Women who are expecting a baby need twice as much iron – and that’s hardly surprising! During pregnancy, the volume of blood in the expectant mother increases by approx. 40%. After all, not only the mother, but also the developing baby must be supplied with oxygen and micronutrients. Iron is a particularly important nutrient in this context. This trace element is a central building block of the red blood pigment and is involved in blood formation and oxygen transport in the body. Many other metabolic processes are also iron-dependent. These include cell division, energy metabolism and immune defence.
A good iron supply is important not only during pregnancy, but also for women who wish to have children. A current study associated decreased ferritin levels (< 30 μg/L) with unexplained infertility (Holzer I. et al., 2023). In addition, another study conducted by Harvard researcher Dr Jorge Chavarro showed that women who take iron supplements have a lower risk of ovulatory infertility compared to those who do not take them. For this reason, women who want to have a child should not only take folic acid on a preventive basis, but they should also have their iron levels determined as a precaution.
Pregnancy is a miracle of evolution. It’s no wonder that expectant mothers feel tired and weak every now and then due to this impressive feat of strength. However, if other persistent symptoms occur, this could indicate iron deficiency:
Pregnant women who notice these or similar complaints should make an appointment with their doctor as soon as possible. In principle, however, the monitoring of iron levels during pregnancy is part of the standard repertoire of gynaecological examinations anyway.
Iron deficiency during pregnancy is not uncommon in our latitudes either. Mothers-to-be who suffer from it often feel tired and worn out. In addition, other symptoms such as brittle nails, cracks in the corner of the mouth and problems concentrating can also be noticeable (see above). If maternal iron stores are running out, the most severe form of iron deficiency, so-called iron deficiency anaemia, can also occur.
A slight iron deficiency is not yet a problem for the developing baby, as it is able to “snack” on the maternal reserves. Only persistent and serious iron deficiency anaemia can cause the child's organism to falter as well. However, in order to ensure that the iron levels in pregnant women do not become seriously depleted, checking the mother’s iron levels is standard in her check-ups.
In pregnant women, the iron value in the blood, the so-called Hb value (= haemoglobin value), is routinely determined. If this value falls in the 2nd trimester below 10.5 g/dl, or in the 1st and 3rd trimesters below 11 g/dl blood, the expectant mother has iron deficiency anaemia. In addition, the erythrocyte count also provides information about possible anaemia. Fewer than 3.9 million red blood cells per μg of blood indicate iron deficiency.
In order to diagnose iron deficiency without anaemia, the ferritin level (ideally incl. the transferrin level and transferrin saturation) is used. This value shows the state of the maternal iron supplies. While ferritin levels below 30 μg/l indicate depleted iron stores, values below 15 μg/l indicate that the iron stores are completely empty.
Pregnancy is one of the phases in a woman’s life in which iron deficiency can develop relatively quickly due to the high iron requirement. Not only do mother and child have to be well supplied with iron, but the increased blood volume and growing placenta and uterus also require a lot of iron. These physiological changes are also reflected in the maternal iron requirements. For example, the German Nutrition Society (DGE) recommends twice as much iron per day for pregnant women, i.e. 30 mg iron from all sources, compared with non-pregnant women – because, according to the experts, it is only with this intake that iron deficiency can be prevented during pregnancy.
However, the iron requirement is not the same over the entire 9 months in fact. While hardly any extra iron is needed in the first half of pregnancy, there is a significant increase in demand in the second half. Therefore, expectant mothers should pay special attention to their iron stores and fill up with plenty of iron in their diet. Foods rich in iron include legumes such as lentils and soya beans, red meat, nuts, seeds and certain vegetables such as parsley, watercress and spinach. Especially in the intense 2nd phase of pregnancy, however, normal intake via the diet may no longer be sufficient to meet the absorption needs and this shortfall may be reflected both physically and mentally and/or come to light during a blood test. In this case, after consultation with a medical specialist, supplementation may be recommended.
Expectant mothers who are suffering from iron deficiency can no longer optimise their iron levels through diet alone. Affected women should therefore start iron supplementation as early as possible, which bolsters the maternal iron intake. After just a few weeks, this "Iron Plus" should be reflected in better iron levels and increased well-being.
For women of childbearing age, approximately 15 mg iron daily is recommended. In order to start the pregnancy with good levels, women planning a pregnancy should have their iron status determined in advance. In the case of iron deficiency, a customised iron preparation can be used to work on the levels in a targeted manner. A good supply at the start of pregnancy also reduces the risk of developing iron deficiency over the course of the 9 months.
In order to prevent iron deficiency during pregnancy, the German Society for Nutrition (DGE) recommends that expectant mothers should take a total of 30 mg iron daily from all sources. While the iron requirement barely increases in the first 20 weeks of pregnancy and – if there is no iron deficiency – can be met by a balanced diet rich in iron, the supplementary intake of an iron preparation may be necessary in the last 20 weeks of pregnancy. With the help of a blood analysis, the gynaecologist can check the current iron status and, if necessary, recommend an ideally coordinated iron preparation. Because, in short: Too much iron is also to be avoided in this sensitive time, which is why an individual adjustment is advisable.
More iron is also recommended for new mothers, whether breastfeeding or not – 20 mg daily from all sources should be consumed to compensate for the loss of iron caused by pregnancy. In nursing women, the baby also consumes the mother’s iron.
In order to keep a good eye on iron levels beyond pregnancy, new mothers should take the opportunity to have an iron check. This means that, even after pregnancy, in the event of iron deficiency, an adequate iron preparation can be taken that will react quickly and in a targeted manner.
Gentle plant-based iron preparations are a good choice due to their tolerability during pregnancy. Research confirms that filling up on iron “works” even at low doses. In this way, our organism is able to increase its iron utilisation in the intestine in the event of poor iron supply. As a result, even low doses can be of use in the event of iron shortages. However, plant iron products are not only proven to be effective, they also show particularly good tolerability in application studies. Gentle and effective at the same time, plant-based iron preparations are a good alternative to high-dose iron salt preparations.
Iron syrops can be a great-tasting source of extra iron during pregnancy. However, pregnant women in particular should focus not only on the taste, but also on the quality when selecting products. While many iron syrups contain iron salts, which is not always immediately apparent, there are others that use plant-based extracts as their iron source. Since iron preparations are generally taken over a longer period of time, the selected syrop should definitely be free of unnecessary additives.
Women who become sensitive to the taste of certain foods during pregnancy often prefer taste-neutral iron capsules or tablets. Always opt for quality preparations that were manufactured according to the so-called pure substance principle – i.e. products that do not use unnecessary additives. Iron capsules that use special plant extracts as an iron source, are considered particularly gentle and well tolerated.
Whether – and if yes, for how long – iron should be taken during pregnancy depends on the individual starting position of the expectant mother. In order to ensure an ideal iron supply, the treating gynaecologist should be consulted. He or she may recommend an adequate iron therapy based on blood tests.
Conclusion: Pregnancy is a feat of strength during which twice as much iron as normal is required. So it is hardly surprising that iron deficiency is not uncommon in expectant mothers. A diet rich in iron and regular iron checks are therefore key in this special phase of life. Pregnant women who already have an iron deficiency can no longer bring their levels up to par through nutrition alone. In this case, high-quality iron preparations (always in consultation with medical specialists) can be the answer for expectant mothers.
Pregnant women can fill their iron reserves by eating legumes such as lentils and soya beans, red meat, nuts, seeds and certain vegetables such as parsley, watercress and spinach. When iron-rich foods are combined with vitamin C (e.g. peppers, broccoli, citrus fruits), iron absorption is further improved.
If your iron level (Hb level) is too low during pregnancy, you may develop so-called iron deficiency anaemia.
Fatigue, paleness, headaches and concentration problems can be signs of iron deficiency during pregnancy. However, only a blood test can provide clarity on this.
It is critical if the Hb value in the blood falls below 10.5 g/dl in the 2nd trimester, or if it falls below 11 g/dl blood in the 1st and 3rd trimesters. The expectant mother is then said to have iron deficiency anaemia. In order to prevent this from happening in the first place, iron supplementation should be considered in the case of reduced iron reserves (ferritin levels below 30 μg/L), as always in consultation with a doctor.
As a rule, the gynaecologist checks the iron level for the first time at the first check-up. Depending on the initial Hb value, this is then checked on a monthly basis or once every trimester.
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