Vitamin D Deficiency During Pregnancy

Why Is Vitamin D Important in Pregnancy?

Vitamin D is a fat-soluble vitamin and a key modulator of calcium metabolism. During pregnancy, the calcium demands increase in the third trimester. Vitamin D is essential for maternal health, fetal skeletal growth, and optimal maternal and fetal outcomes.

The two types of vitamin D include,

• Vitamin D3 (Cholecalciferol) - This is generated in the skin by exposure to sunlight.

• Vitamin D2 (Ergocalciferol) - This is derived from plant sources.

Both types of vitamin D can be absorbed in the gut. In addition, vitamin D is present in fish and some plants but not in significant amounts in meat, poultry, dairy, or commonly eaten fruits and vegetables.

Vitamin D plays an important role during pregnancy:

• Vitamin D helps with calcium absorption and forming a baby's skeletal development.

• It protects both the mother and the developing fetus from infections.

• Some researchers suggest that adequate vitamin D levels reduce the risk of gestational diabetes.

• Maintaining adequate vitamin D levels reduces the risk of preterm labor.

What Foods Are Rich in Vitamin D?

The following foods are rich in vitamin D-

• Fish liver oil (cod liver oil).

• Fatty fish.

• Eggs or egg yolks.

• Beef liver.

• Salmon.

• Fortified foods like milk, bread, cheeses, orange juice, cereals, and yogurts.

However, the relative contribution of dietary vitamin D in humans is low compared with the endogenous production of vitamin D from sunlight.

What Are the Various Stages of Vitamin D Deficiency During Pregnancy?

The stages of vitamin D deficiency during pregnancy are as follows:

• In the early stages, there may be no apparent symptoms. These may affect fetal development and increase the risk of gestational diabetes.

• In moderate deficiency, the symptoms include fatigue, weakness, bone pain, and mood disturbances. Compromised fetal growth may increase the risk of preterm birth.

• In severe deficiency, the symptoms include muscle cramps and skeletal deformities. There may be fetal developmental abnormalities.

• Untreated vitamin D deficiency during pregnancy can lead to maternal fractures and low birth weight babies.

What Dose of Vitamin D Supplementation Is Safe in Pregnancy?

The Food and Nutrition Board recommends an adequate vitamin D intake of 600 IU per day for pregnant and non-pregnant women aged up to 50 years. Most prenatal vitamins for pregnant women contain 400 IU of vitamin D per tablet. Pregnant women need to discuss their vitamin D needs with their healthcare providers.

The recommended dose of vitamin D supplementation is described below:

• The recommended daily dose of vitamin D for infants below 12 months of age is 400 IU.

• For children between the ages of one to 13 years, is 600 IU.

• For teens between 14 to 18 years of age is 600 IU.

• For adults between 19 to 70 years of age is 600 IU.

• For adults who are above 71 years and older, the recommended dose is 800 IU.

• For pregnant and lactating women, the recommended daily dose of vitamin D is 600 IU.

What Are the Risk Factors for Vitamin D Deficiency During Pregnancy?

The following factors can increase the risk of vitamin D deficiency in pregnant women:

• Obesity - High body fat levels can limit the body's ability to absorb vitamin D from the skin.

• People with darker skin tones (with more melanin pigment) have less vitamin D production.

• Smoking.

• Low dietary vitamin D intake, especially vegetarian diet.

• Medications like steroids, cholesterol-lowering drugs, anti-seizure medications, or diuretics interfere with vitamin D absorption.

• Disorders like Crohn's (inflammatory bowel) or celiac disease (an autoimmune disorder that damages the small intestine) involve a decreased ability to absorb dietary fat, leading to less vitamin D absorption.

• Malabsorptive syndromes like cystic fibrosis (a genetic disorder that damages the lungs), cholestatic liver disease (bile formation impairment), inflammatory bowel disease, and short gut syndrome.

• Extensive skin covered by clothes.

• Northern latitudes (winter or springtime).

• Limited exposure to the sun.

• Regular use of sunscreens.

• Aging - The ability of the skin to synthesize vitamin D decreases with age.

What Are the Symptoms and Effects of Vitamin D Deficiency During Pregnancy?

Inadequate levels of vitamin D in pregnant women may lead to the following outcomes,

1. Symptoms of Vitamin D Deficiency in Mothers:

• Preeclampsia (high blood pressure during pregnancy) and hypertensive disorders.

• Bone pains.

• Muscle aches (myalgia).

• Weakness.

• Softened bones.

2. Effects of Vitamin D Deficiency on the Fetus and Newborn:

• Infant size is less than normal.

• Low birth weight babies.

• Poor skeletal mineralization leads to conditions like congenital rickets, osteopenia (loss of bone mineral density), or craniotabes (softening of skull bones).

• Impaired fetal bone ossification.

• Larger fontanelles (impaired skull ossification).

3. Vitamin D Deficiency During Lactation:

• Babies who are extensively breastfed are at a higher risk of vitamin D deficiency because human milk contains very low levels of vitamin D. However, formula-fed babies receive optimum amounts of 400 IU of vitamin D per liter.

• Breastfed infants from vitamin D-deficient mothers can sometimes manifest life-threatening conditions like hypocalcemic seizures and dilated cardiomyopathy.

4. Effects of Vitamin D Deficiency in Childhood:

• Asthma.

• Type 1 diabetes mellitus.

How to Get a Sufficient Amount of Vitamin D During Pregnancy?

Vitamins and minerals are an essential part of a pregnant woman's diet.

Following dietary and lifestyle changes can be made to cope with the deficiency of vitamin D-

• Daily sunbathing for at least 10 to 30 minutes of midday sunlight.

• The diet can include oily fish (salmon, sardines, mackerel, or herring), eggs, mushrooms, or meat.

• Eating fortified breakfast cereals, bread, cheeses, and dairy products.

• Prenatal vitamins as recommended by doctors.

What Happens to Vitamin D Toxicity During Pregnancy?

The highest daily dose that can be given during pregnancy is 4,000 IU/day. Excessive vitamin D intake during pregnancy can result in the risk of hypercalcemia (high calcium content) in the fetus.

Can Vitamin D and Calcium Be Taken During Pregnancy?

Yes, vitamin D and calcium can be taken together during pregnancy. Vitamin D helps the body absorb calcium, essential for maintaining bone health and supporting fetal development. Many prenatal supplements contain calcium and vitamin D to ensure that pregnant women meet their daily requirements for these nutrients. Pregnant women need to consult with their healthcare provider before starting any new supplements to determine the appropriate dosage.

Conclusion:

Vitamin D plays a very vital role in the human body. It is responsible for maintaining healthy bones and teeth and regulating inflammation and the body's immune function. The demand for vitamins and minerals increases as the baby grows inside the mother during pregnancy. Therefore, a pregnant mother must take special care of her nutrition.

A pregnant woman must take prenatal vitamins and supplements as prescribed by the doctor. Vitamin D deficiency can cause very severe maternal and fetal outcomes. Thus, maintaining adequate vitamin D levels through diet, daily exposure to sunlight, and vitamin D supplements are essential for a healthy pregnancy and a baby's growth and development. The vitamin D levels should be checked regularly during pregnancy so that doctors can prescribe the required supplements.