A pregnant woman requires the right amount of nutrients for healthy development of the fetus. It has been reported that during the first three months of pregnancy, a woman does not require additional calorie intake compared to the next two trimesters, when an additional 300 calories per day are essential for the baby to grow to reach proper birth weight. A drastic increase or decrease in weight during pregnancy can lead to health hazards for the mother and the baby. With the advent of vegetarianism, it is important to understand some shortcomings of this type of diet during pregnancy and put in place practices to overcome the same, to aid in the overall healthy development of the fetus.

Common problems associated with vegetarianism during pregnancy:

Developmental issues in the fetus:

Protein is considered an essential building block and is imperative for the development of the fetus. The pregnant woman needs to consume protein rich food to get the complete benefits of essential amino acids. According to the Physicians Committee for Responsible Medicine, pregnant women in the second and third trimester have to consume extra protein, since protein, fat, and minerals are deposited in the fetal tissues and placenta in order for the fetus to gain the normal weight before birth.

Though plant protein is sufficient, a variety of sources need to be considered to get the requisite amount of protein. These include soy, peanut butter, nuts, quinoa, tofu, etc.

Hypospadias:

Hypospadias is a male birth defect where the opening on the penis for the urethra is not located where it should be. This defect is attributed to the high levels of phytoestrogens that are found in a vegetarian diet. A nationwide study in the USA has listed one case of hypospadias in every 270 births in the year 1990. A study conducted in the year 2000 in the UK reveals that vegetarian mothers have a 4% chance of delivering a baby with hypospadias. An association has been reported between hypospadias and nutrients like choline, methionine, vitamin B12, etc., all of which are scarce in a vegetarian/vegan diet. 

Iron deficiency:

Low iron intake can lead to low birth weight and cognitive problems in infants. While meat and fish are rich in iron, many plant foods also contain iron. The average iron requirement for pregnant women is estimated to be roughly 22mg/day. Since iron is the main component of hemoglobin, pregnant women with low hemoglobin (less than 8gm/dL) carry a risk of anemia that might lead to fetal growth abnormalities and pre-term birth.

Iron from an animal source is called heme-iron and is absorbed at a better rate than the plant-based iron or non-heme iron. Therefore, it is important for pregnant vegetarian women to attain the optimal level of suggested iron intake for their pregnancies to proceed normally.

Vitamin B12 deficiency:

A study compared serum vitamin B12 concentration in a lacto-ovo vegetarian diet and low meat consumers. Vitamin B12 deficiency was found in both categories when compared to a meaty western diet. Since low serum vitamin B12 is associated with macrocytic anemia, neurologic complexities, and cognitive impairments, pregnant vegetarian women may need a vitamin B12 supplement to ensure proper fetal development.

Thus, the risk of nutrient deficiency is high in pregnant women who follow a vegetarian diet, especially those who avoid dairy and eggs. Pre-natal vitamin supplements are available that can compensate for iron, vitamin B12, folic acid, omega-3 fatty acids, and essential nutrients in pregnant vegetarian women. The right vegetarian food chart can help compensate for the nutrient loss.

References:

Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. Washington, DC: National Academy Press; 2002.

(2003). Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets. J Am Diet Assoc, 103, pp.748-756.

Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, Institute of Medicine. Dietary reference intakes for individuals, elements. Washington, DC: National Academy Press; 2004.

Koebnik, C., Hoffmann, I., Dagnelie, P.C., Heins, U.A., Wickramasinghe, S.N., Ratnayaka, I.D., et al. Long-term ovo-lacto vegetarian diet impairs vitamin B-12 status in pregnant women. J Nutr. 2004, 134, pp. 3319-3326.

Norris, J. (2012 Jun). Hypospadias and Vegetarian Diets. Retrieved from http://www.veganhealth.org/articles/hypospadias

(2013 Jul 15). What Can I Do to Promote a Healthy Pregnancy? Retrieved from http://www.nichd.nih.gov/health/topics/preconceptioncare/conditioninfo/pages/healthy-pregnancy.aspx

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