Vitamin B12 Deficiency in Expecting Mothers

Vitamin B12, also called cobalamin, is a water-soluble vitamin essential for red blood cell formation, neurological function, and DNA synthesis. During pregnancy, B12 requirements increase to support the rapid cell division occurring in both the mother's body and the developing fetus. A deficiency arises when intake or absorption of this vitamin is inadequate to meet these heightened demands.

Vitamin B12 deficiency is a particularly relevant concern in India, where a large proportion of the population follows vegetarian diets. Studies have shown that up to 70% of Indian adults may have suboptimal B12 levels. Since vitamin B12 is found almost exclusively in animal-derived foods, vegetarian and vegan women are at the highest risk of deficiency during pregnancy.

The body can store vitamin B12 in the liver for several years, but during pregnancy these stores are drawn upon more rapidly. Women who enter pregnancy with already low B12 reserves may develop clinically significant deficiency as the pregnancy progresses, particularly during the second and third trimesters when fetal demands peak.

Dietary insufficiency is the primary cause of B12 deficiency, especially among vegetarian and vegan women. Plant-based diets provide negligible amounts of B12 unless fortified foods or supplements are included. Even lacto-vegetarian diets that include dairy and eggs may not provide enough B12 to meet the increased requirements of pregnancy, depending on the quantity consumed.

Malabsorption disorders represent another important cause. Conditions such as pernicious anemia (an autoimmune condition affecting intrinsic factor production), atrophic gastritis, celiac disease, and Crohn's disease can impair B12 absorption in the gut. Certain medications, including proton pump inhibitors and metformin, can also reduce B12 absorption over time.

Women who have undergone bariatric surgery or have a history of chronic gastrointestinal issues may have reduced capacity to absorb B12 from food. Additionally, frequent use of antacids or acid-reducing medications can lower stomach acid production, which is necessary for releasing B12 from food proteins before absorption.

Early symptoms of B12 deficiency are often mild and nonspecific, including fatigue, weakness, and a general feeling of malaise. As the deficiency progresses, neurological symptoms may emerge, such as tingling or numbness in the hands and feet, difficulty with balance, and memory problems. These nerve-related symptoms can be mistaken for pregnancy-related discomforts.

B12 deficiency can cause a type of anemia called megaloblastic anemia, characterised by abnormally large red blood cells. Symptoms include pallor, rapid heartbeat, shortness of breath, and a smooth, sore tongue. Some women may experience mood changes, including depression and irritability, which can overlap with normal emotional fluctuations during pregnancy. A simple blood test measuring serum B12 and methylmalonic acid levels can confirm the diagnosis.

For the mother, B12 deficiency increases the risk of megaloblastic anemia, which reduces the oxygen-carrying capacity of the blood and causes persistent fatigue. Neurological damage from prolonged deficiency, if left untreated, can become irreversible. Low B12 levels have also been associated with elevated homocysteine, a risk factor for cardiovascular complications and pregnancy loss.

For the baby, adequate maternal B12 is essential for normal brain and nervous system development. Deficiency during pregnancy has been linked to neural tube defects, intrauterine growth restriction, and preterm birth. Babies born to B12-deficient mothers may themselves have low B12 stores, leading to developmental delays, feeding difficulties, and failure to thrive in early infancy.

Research from Indian studies has highlighted that maternal B12 deficiency may also affect the baby's metabolic programming, potentially increasing the child's risk of insulin resistance and related conditions later in life. These findings underscore the importance of addressing B12 status early in pregnancy or, ideally, before conception.

Animal-derived foods are the primary natural sources of vitamin B12. Eggs, milk, curd, paneer, fish, and lean meats provide meaningful amounts. For non-vegetarian women in Visakhapatnam, including locally available fish and seafood in regular meals can help maintain adequate B12 levels. Eggs and dairy products are accessible options for lacto-ovo vegetarian families.

For strictly vegetarian or vegan women, fortified foods are essential. Look for B12-fortified plant milks, breakfast cereals, and nutritional yeast. However, relying solely on fortified foods may not guarantee adequate intake, making supplementation advisable. Your doctor may recommend oral B12 supplements or, in cases of malabsorption, sublingual tablets or intramuscular injections.

Starting B12 supplementation before conception is ideal, especially for vegetarian women. Prenatal vitamins that include B12 are widely available and should be part of the pregnancy nutrition plan. Discuss your dietary pattern with your healthcare provider so that appropriate testing and supplementation can be arranged early in your pregnancy journey.

All women following vegetarian or vegan diets should have their B12 levels tested early in pregnancy or during preconception planning. If you experience symptoms such as persistent fatigue, tingling in your extremities, mood changes, or difficulty concentrating, bring these to your doctor's attention. Blood tests for serum B12, complete blood count, and methylmalonic acid can help establish the diagnosis.

Your obstetrician in Visakhapatnam can guide you on the appropriate form and dosage of B12 supplementation based on your levels and dietary habits. If you have a condition that affects B12 absorption, more frequent monitoring and alternative delivery methods such as injections may be recommended. Early identification and treatment of B12 deficiency can prevent neurological complications and support your baby's optimal development.