Vitamins During Pregnancy

According to the research of the Institute of Nutrition, in fact, not one of the modern Russian women comes into pregnancy having in the body all the necessary vitamins and minerals in sufficient quantities. Regardless of age, place of residence, income level, profession, social status, each expectant mother suffers from a partial lack of one or another vitamin or mineral. Most pregnant women (70%) have a deficiency of three or more vitamins.

Studies of the Institute of Nutrition showed ^[3] :

• each of a hundred pregnant women has a deficiency of B vitamins;
• ninety-five out of a hundred pregnant women lack carotenoids (precursors of vitamin A);
• half of all pregnant women lack ascorbic acid .

A person needs a small (compared to proteins , carbohydrates and fats ) amount of vitamins and minerals: thousandths or even millionths of a gram. But food cannot provide this rate of matter.

During pregnancy and lactation, hypovitaminosis of vitamins D, B6, folic acid (B9), as well as a lack of iron , calcium , iodine and zinc are especially dangerous. Due to malnutrition, many women enter pregnancy with the already indicated hypovitaminosis. ^[4] To fill the deficiency, vitamin-mineral complexes are prescribed at the planning stage and during pregnancy.

Risk of pathological deficiency of vitamins and minerals

In the first trimester of pregnancy, a deficiency of vitamins and microelements can lead to fetal malformations, intrauterine developmental disorders, and fetal death. In this perinatal period, the laying of organs, of individual groups of cells and tissues occurs, the differentiation of cells occurs, the fetus is especially vulnerable and dependent on the full supply of iodine, folic acid and many essential micronutrients. In the II and III trimesters of pregnancy, a lack of vitamins does not cause obvious abnormalities of intrauterine development, but often leads to impaired organ formation and causes problems in the work of the child's cardiovascular, nervous, endocrine and digestive systems. ^[one]

According to the recommendations of the Ministry of Health and Social Development ^[5], vitamin therapy is carried out with:

• periconceptional prophylaxis;
• normal pregnancy ;
• premature termination of pregnancy;
• preeclampsia ;
• diseases of the cardiovascular system in pregnant women;
• inflammatory kidney disease in pregnant women;
• physiological postpartum period.

Vitamin B6 (Pyridoxine)

Vitamin B6 is necessary for the production of amino acids from which proteins are synthesized. He participates in hematopoiesis, regulates the processes of inhibition in the nervous system (reduces irritability, aggressiveness). A lack of this vitamin is often one of the causes of early toxicosis. For the fetus, B6 ensures the proper development of the brain and nervous system. ^[6]

Deficiency of vitamin B6 in a woman’s body causes disturbances in the nervous system, anemia , and diseases of the gastrointestinal tract. In pregnant women, vitamin B6 deficiency increases the likelihood of developing a convulsive syndrome. Symptoms of pyridoxine deficiency during pregnancy are nausea, persistent vomiting, decreased appetite, irritability, and insomnia. ^[4] .

Folic Acid (Vitamin B9)

Folic acid is necessary for the formation of fetal tissues, renewal and restoration of mother cells [1]. Experimental data show that taking folic acid some time before conception and during pregnancy reduces the risk of neural tube defects in newborns by 75% ^[7] .

Folic acid plays an important role in the formation of placental tissue and new blood vessels in the uterus, so a lack of folic acid during pregnancy can lead to its premature termination ^[1] .

Folic acid deficiency can occur after 1-4 weeks, depending on the characteristics of nutrition and the state of the body. Early symptoms of vitamin B9 deficiency: fatigue, irritability, loss of appetite.

Vitamin B12

Vitamin B12 plays a large role in ovulation processes, therefore it is necessary for the onset of pregnancy. A lack of this substance can lead either to a lack of ovulation or to a halt in the development of a fertilized egg , which leads to a miscarriage at an early stage of pregnancy. ^[one]

Vitamin B12 deficiency in infants occurs with maternal malnutrition . Also, a lack of this vitamin is felt by children whose mothers follow a vegetarian diet ^[1] .

Vitamin E (tocopherol)

Vitamin E is involved in the processes of tissue respiration and the metabolism of proteins, fats and carbohydrates. Vitamin E is also an antioxidant , it protects the body from the harmful effects of free radicals .

With hypovitaminosis E, a woman feels an increasing general weakness, muscle pain occurs, due to which involuntary abortion is possible.

Vitamin E deficiency is especially dangerous for premature babies. Lack of this substance causes visual impairment and is accompanied by hemolytic anemia ^[1] .

Specialists from the University Medical Center of Rotterdam believe that excessive intake of vitamin E during pregnancy can cause a child to have heart problems.

A survey was conducted of 276 women whose children had heart problems at birth and 324 women whose children were born completely healthy.

It turned out that women whose children were born with heart defects consumed a higher dose of vitamin E during pregnancy than everyone else.

The study showed that children of women who during the first two months of pregnancy took more than 14.9 mg of vitamin E per day were 9 times more likely to be born with congenital heart defects.

Calcium (Ca)

During pregnancy, the unborn child needs about 30 grams of calcium for normal development. And most of it - in the last trimester of pregnancy, when the formation of the skeleton . However, calcium is needed not only for bones. At an earlier date, this mineral is required for the proper formation of the nervous system , heart and muscle tissue.

If insufficient calcium comes from food, the fetus accumulates calcium from the mother’s skeleton. Therefore, with an increase in the gestational age in women, calcium deficiency and osteopenic syndrome may gradually develop.

The situation is complicated by the fact that during pregnancy the volume of fluid removed from the body increases, and with it the loss of calcium also increases. In addition, during pregnancy, calcium metabolism is adversely affected by a diet rich in cereal products (phytates), sugars and other carbohydrates - they lower the pH level in the blood and thereby contribute to the excretion of calcium from the body . This explains the mandatory appointment of calcium preparations during pregnancy ^[1] . however, calcium intake in the last trimester is fraught with ossification of the skull of the unborn child, which can lead to a difficult birth. There is another version that ossification of the fontanel is genetically determined and calcium intake does not affect the birth process.

Iron (Fe)

The iron in the composition of hemoglobin provides oxygen to all organs of not only the mother, but also the child. Therefore, with iron deficiency, the fetus does not have enough oxygen, as a result, the risk of premature birth and the birth of a dead baby increases. Lack of iron during pregnancy causes atonic uterine bleeding . In addition, a low iron content leads to a weakening of immunity, as a result of which infections develop, wound healing slows down ^[1] .

That is why pregnancy and breastfeeding are physiological conditions when a woman needs a long iron intake to prevent iron deficiency anemia in both mother and baby ^[4] .

IDA - iron deficiency anemia is detected during pregnancy in 9 cases out of 10. Pregnant anemia is the most common type of pathological conditions of pregnancy ^[1] .

Iodine (I)

Iodine is necessary for both the mother and the unborn child, since it is used in the synthesis of hormones , on which the production of protein in almost any cell of the body depends. In addition, thyroid hormones are necessary for the formation of the central nervous system and skeleton of the unborn child.

Replenishment of iodine deficiency should begin already in early pregnancy to prevent congenital malformations of the fetus, endemic cretinism (mental retardation), hypothyroidism . The use of iodine preparations throughout pregnancy almost completely prevents the formation of goiter, both in the mother and in the fetus ^[4] .

In recent years, in Russia there has been a significant increase in thyroid diseases in pregnant women. The main cause of these diseases is insufficient iodine intake. This is due to the fact that almost the entire territory of Russia is iodine deficient. Iodine deficiency is exacerbated by economic and environmental factors ^[1] .

Indications for use of iodine inside:

• prevention of diseases associated with iodine deficiency (in preparation for pregnancy, during pregnancy and during lactation);
• treatment of goiter caused by iodine deficiency ^[8] .

Zinc (Zn)

Zinc deficiency, as well as metabolic disorders, can have serious consequences that occur during pregnancy and affect the growth of the fetus and newborn ^[1] .

The only source of zinc for the fetus is the mother's body. The zinc content in the female body affects the growth of the fetus and the weight of infants at birth. Moderate zinc deficiency leads to complications during childbirth and labor, which can ultimately cause an undesirable pregnancy outcome. In addition, the amount of zinc in the mother’s body during pregnancy affects the growth of infants and the incidence of diseases in infants ^[9] .

A number of studies have shown that zinc deficiency is associated with the occurrence of pregnancy complications such as prolonged labor, postpartum hemorrhage, involuntary abortion , and the development of birth defects.

Zinc deficiency can be teratogenic, that is, causing a violation of embryonic development and lead to the formation of defects in the neural tube of the fetus.

In newborns, zinc deficiency is associated not only with dwarfism and stunting, but also with impaired immunity, an increase in the incidence rate, and, in a number of countries, with mortality from infectious diseases.

Especially high risk of zinc deficiency in premature babies.

A number of studies have shown that the addition of zinc to the diet of mothers leads to an increase in weight gain in children who are breast-fed compared to a group of children whose mothers did not receive additional zinc ^[10] .

Iron preparations

Many foods can reduce the effect of iron supplements. Legumes and nuts reduce iron absorption due to the presence of phytates in them. Polyphenols contained in tea also negatively affect the absorption of iron. Do not drink iron preparations with milk or other dairy products: calcium and phosphates, which are rich in milk, interfere with the absorption of iron. Leafy vegetables and eggs also impede the absorption of iron, but to a lesser extent. Iron absorption is also adversely affected by certain medications: tetracycline and fluoroquinolone antibiotics , as well as vitamin E ^[11] .

Calcium preparations

Components of many foods can convert calcium into an inaccessible form. Leguminous products rich in phytates and phosphorus make calcium absorption very difficult. Many vegetables (especially sorrel, spinach , currant) contain oxalic acid, which irreversibly binds calcium. Alcohol , fats, and tea have a slightly lesser effect on calcium absorption ^[4] .

Zinc preparations

Many products also interfere with the absorption of zinc - the substances contained in them form insoluble compounds with it. Legumes are most active in this regard because of the high concentration of phytic acid in them. Green vegetables have a negative effect on zinc absorption. Fiber and eggs also impede the absorption of zinc.

Most minerals compete with zinc for absorption. Therefore, iron, calcium, and copper preparations should not be taken simultaneously with zinc.

Zinc absorption worsens tin , which is used in the coating of cans, and can enter the body. Given the large number of undesirable interactions of various substances with zinc, it is better to avoid taking zinc preparations at the same time as food. It is most rational to take zinc-containing drugs no less than 2 hours after eating ^[9] .

Vitamin A ( Retinol )

Food, unless they contain nitrates , does not inhibit the absorption of vitamin A. But when absorbing vitamin A, another difficulty arises. Successful absorption of vitamin A requires the presence of fats, vitamin E and proteins. With a deficiency of any of these components, the absorption of vitamin A is reduced, even if the food is enriched ^[12] .

According to the norms of daily intake of vitamins adopted in the Russian Federation, a pregnant woman should consume no more than 1200-1400 micrograms of vitamin A, which corresponds to 3960 - 4620 IU. Consumption of vitamin A in unreasonably high dosages (more than 10,000 IU / day) is dangerous for pregnant women, as this can lead to defects in the development of fetal organs and tissues. Given the risk of developing the above conditions, it is advisable to use beta-carotene as a source of vitamin A. Beta-carotene is converted in the body to vitamin A in certain quantities necessary for the body. Beta-carotene does not have the toxic effect characteristic of an excess or overdose of vitamin ^[13] .

Vitamin B1 ( Thiamine )

Vitamin B1 should not be taken with tea or coffee. These drinks reduce the intake of thiamine in the body. In addition, at the same time with this vitamin, it is undesirable to take sulfanilamide-based preparations.

Interaction: calcium-iron

Calcium and iron have the same mechanism of absorption in the body ^[14] . Therefore, while entering the gastrointestinal tract, they compete for assimilation ^[15] . Numerous studies have shown that calcium significantly reduces iron absorption in the gastrointestinal tract (about 2 times) ^[11]

In one study, a group of 12 physically healthy women received drugs containing either calcium and iron, or only iron, but two times less than in the first drug. However, the blood in women contained the same amount of iron ^[16] . This suggests that the absorption of iron from both drugs is almost the same. Подобные данные были получены и в других исследованиях, где в группу наблюдения входили беременные женщины, принимавшие препараты с различным содержанием кальция ^[2] .

На основе этих работ учёные дали рекомендации принимать витаминно-минеральные препараты с содержанием кальция не более 250 мг и железа 60 мг — так обеспечивается всасывание того количества железа, которое адекватно рекомендованной дозе в 30 мг ^[14] .

Предотвратить нежелательные взаимодействия кальция и железа можно и другим способом: употреблять продукты, содержащие кальций (молоко, зелёные овощи, рыбу), отдельно от богатой железом пищи (мясо, печень ). А при выборе витаминно-минеральных препаратов следует отдавать предпочтение тем, которые состоят из нескольких таблеток, принимаемых с интервалом в несколько часов в течение суток. При этом кальций и железо должны находиться в разных таблетках.

Однако стоит учесть, что препараты железа для перорального приёма иногда плохо переносятся, и это часто ограничивает их применение на поздних сроках беременности. Поэтому целесообразно принимать витаминно-минеральные комплексы с железом уже в период планирования беременности и на её ранних сроках ^[17] .

Другие взаимодействия и аллергические реакции

Если витамин B12 и витамин С ( аскорбиновая кислота ) находятся в одной таблетке, то от 10 до 30 % витамина В12 окисляется витамином С и превращается в бесполезные и вредные для человека соединения ^[18] .

Магний затрудняет усвоение железа в желудночно-кишечном тракте. Точно так же за усвоение конкурируют цинк и хром . Для усвоения витамина В12 необходим кальций. А для усвоения кальция необходим витамин D3. (Такие взаимодействия между веществами называют синергичными) ^[4] .

Негативные взаимодействия микронутриентов могут проявляться не только в уменьшении степени усвоения того или иного компонента. Иногда такие взаимодействия принимают очень неприятные формы. Например, при совместном приёме витаминов В12 и В1 возможны реакции аллергического типа ^[19] .

Итак, с одной стороны, во время беременности необходим приём витаминов и минералов. С другой стороны, не все витамины и минералы могут усваиваться в полном объёме, а некоторые даже могут вызвать аллергическую реакцию при совместном приёме. Чтобы избежать нежелательных реакций организма на приём витаминов и минералов, необходимо принимать антагонистические микронутриенты отдельно, а синергичные — вместе. Интервал между приёмами должен составлять 4-6 часов, что практически исключает отрицательные взаимодействия.

• Vitamins
• Совместимость микронутриентов
• Биологически значимые элементы

• Babior BM, Peters WA, Briden PM, Cetrulo CL Pregnant women's absorption of iron from prenatal supplements // J Reprod Med. 1985. 30(4): 355-7. PMID 4009554
• Seligman PA, Caskey JH, Frazier JL, Zucker RM, Podell ER, Allen RH Measurements of iron absorption from prenatal multivitamin—mineral supplements // Obstet Gynecol. 1983. 61(3): 356-62.
• Wieringa FT, Combined Iron and Zinc supplementation in Infants… // J Nutr. 2007 Feb;137(2):466-71
• Стрижаков А. Н., Буданов П. В.. Синергичная витаминотерапия — основа оптимизации предгравидарной подготовки и ведения беременных. (недоступная ссылка с 12-10-2016 [1058 дней])
• Ших Е. В. Клинико-фармакологические аспекты применения цинкосодержащих комплексов во время беременности // Гинекология. — Т. 8. — 2006. — № 5-6.
• Shikh E.V. Rational vitamin therapy for pregnant women // Russian Medical Journal: “Mother and Child”. - 2006. - T. 14. - No. 1. - P. 253. (unavailable link from 12-10-2016 [1058 days])

• Folic Acid and Pregnancy
• Calcium during pregnancy: why, how and when
• Iodine during pregnancy
• Why do future mothers need zinc?
• Trimester Vitamins