Abstract: Vitamin A is essential for fertility, pregnancy, and overall health. This fat-soluble vitamin has two main forms that act differently in the body; one found mainly in animal products and one from plants. Both forms of vitamin A support cell differentiation, vision, immune function, red blood cell formation, skin health, and reproduction health. During the 3rd trimester of pregnancy, there is an increased risk of vitamin A deficiency, particularly among lower-income populations. Deficiency during pregnancy can have short, and long-term effects for both mom and baby. Consequences of insufficiency range from increased risk of anemia for mom to childhood or adulthood schizophrenia later in life for your baby. Adequate vitamin A is also crucial to support the longevity and health of breastfed infants. There is a risk of vitamin A toxicity, particularly from supplementation, so it is essential to be mindful of the type and how much vitamin A you are intaking.

What Is Vitamin A, And Why Do I Need It?

Vitamin A is a fat-soluble vitamin that exists in 2 main categories: preformed vitamin A (retinol, retinyl esters) and provitamin A (carotenoids). 

Preformed vitamin A is found in animal products, fortified foods, and supplements. This form is more bioactive than provitamin A. 

Provitamin A carotenoids are found in vegetables such as sweet potatoes, spinach, and kale. The main carotenoids found in the diet are beta-carotene, alpha-carotene, and beta-cryptoxanthin. These convert into retinol; however, because it takes energy to convert and there are other components within carotenoids, these foods are less bioactive. Although the carotenoids are not the most bioactive form of vitamin A, the antioxidant activity of this form surpasses that of preformed vitamin A.

Back in week 17,  we introduced vitamin A’s role in pregnancy, how you should get it (including an in-depth analysis about the pros and cons of eating liver while pregnant), and supplementation recommendations during pregnancy. 

In this article, we will delve into vitamin A during the 3rd trimester. Specifically, we will focus on:

• Vitamin A deficiency
• Vitamin A for postpartum healing 
• Vitamin A for breastfeeding 

Is Vitamin A Deficiency A Concern? 

During the 3rd trimester of pregnancy, there is an increased risk of vitamin A deficiency. This is because, along with the exponential increase of maternal blood volume, the final phase of fetal development uses a lot of vitamin A, so your body needs to replenish it more often. Although there are no specific differences in recommendations for vitamin A intake per trimester, it is vital to be aware of the signs of deficiency.

During late pregnancy and even postpartum, vitamin A’s role in immune function is critical. For you, it supports the healing process post-birth, reduces the risk of postpartum depression, and can reduce overall weight retention. For your baby, adequate vitamin A supports the ongoing development of vision, and its role in the immune system reduces the risk of infection, inflammation, and oxidative stress. 

Did you know? According to the World Health Organization, 20% or more of pregnant women are deficient in vitamin A 

Vitamin A Deficiency And Insulin Resistance: Effects On Mom And Baby

Insulin regulation is important for regulating your blood sugar and supporting your body's ability to turn food into fuel. Insulin resistance is when your body does not respond to the hormone insulin properly, meaning the glucose, or sugar, cannot be taken up from your blood as easily. Prolonged insulin resistance can lead to type II diabetes mellitus and gestational diabetes. During gestation, cortisol, estrogen, progesterone, and prolactin increase. The excess of these hormones increases the risk of insulin resistance.

Conditions such as gestational diabetes and type II diabetes are found to cause vitamin A deficiency. Gestational diabetes is found to impair vitamin A reserves in newborns and is associated with xerophthalmia and even risk of death for pre-school-aged children.

Did you know? Estrogen can block insulin from taking glucose into the body’s cells. Therefore, high estrogen, such as during pregnancy, raises overall blood sugar. 

What Happens If I Take Too Much Vitamin A?

Vitamin A toxicity is also a risk and can lead to fetal abnormalities and liver damage.  Toxicity of vitamin A is a risk because it is a fat-soluble vitamin; therefore, excess amounts are stored in the liver, increasing the risk of damage.

Typically, this only occurs with large doses of supplementation over a long time (more than 3,000 mcg or RAE 10,000 IU daily). However, some reports have shown excessive liver consumption is linked to toxicity during pregnancy.

In addition to liver damage, although vitamin A is a powerful antioxidant, it becomes a pro-oxidant in substantial doses. Excess vitamin A's pro-oxidant effects can increase preterm labor risk, fetal growth restrictions, and preeclampsia. Additionally, it could influence long-term health consequences of your baby, including increased risk of some types of cancer, obesity, diabetes, and DNA damage. 

Vitamin A For Mom: Healing Post-Birth

Whether a c-section or vaginal birth, the birthing process takes a major toll on your body. As a new mom, you may be thinking about your baby's growth, but it is important to know that your body must heal too! 

Since vitamin A plays such an active role in immune function, it supports the mother’s healing post-birth. There are two main mechanisms by which vitamin A supports maternal recovery after delivery; its antioxidant effects and regulation of innate immune system cells. 

Within the innate immune system, vitamin A can down-regulate inflammatory cytokines, support the development of macrophages, and support T-cell gene expression. Its antioxidant effect can reduce oxidative stress, which increases as a result of birthing vaginally and via c-section. Oxidative stress postpartum is associated with postpartum depression, increased risk of long-term glucose intolerance, and maternal weight retention. 

Choosing To Breastfeed? Vitamin A Is An Essential Nutrient For Breastfed Babies

If you choose to breastfeed, many micronutrients, macronutrients, and phytochemicals within your diet can support your baby's health. Vitamin A is one of those essential micronutrients that help your baby's growth, development, and longevity.

Like during fetal development in the womb, vitamin A in breast milk supports essential processes of cell differentiation, immune support, and red blood cell production. Retinol, the active form of vitamin A, is highest in colostrum right after birth. This is what gives colostrum that yellow color!

Although the specific mechanisms for transferring and secretion of dietary vitamin A from mammary glands, milk-producing glands are still under research, the main transport is via retinol-binding proteins. These proteins can transport vitamin A throughout the blood and to the mammary glands to nourish your baby. Additionally, while in the cells, vitamin A acts on specific target genes, particularly genes important for immune function. 

Did you know? The mammary glands during the first six months of breastfeeding provide 60 times more vitamin A than your baby receives throughout pregnancy! 

Summary

Vitamin A is essential for fertility, pregnancy, and overall health. This fat-soluble vitamin has two main forms that act differently in the body; one found mainly in animal products and one from plants. Both forms of vitamin A support cell differentiation, vision, immune function, red blood cell formation, skin health, and reproduction health. 

During the 3rd trimester of pregnancy, there is an increased risk of vitamin A deficiency, particularly among lower-income populations. Deficiency during pregnancy can have short, and long-term effects for both mom and baby. Consequences of insufficiency range from increased risk of anemia for mom to childhood or adulthood schizophrenia later in life for your baby. Additionally, there is a significant relationship between vitamin A and insulin resistance.

Adequate vitamin A is also crucial to support the longevity and health of breastfed infants. There is a risk of vitamin A toxicity, particularly from supplementation, so it is important to be mindful of the type and how much vitamin A you are intaking.

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