Thiamine Deficiency


The information provided below is for readers based in the United States of America. Readers outside of the United States of America should seek the information from local sources.

What is thiamine deficiency during pregnancy?

Thiamine (thiamin) deficiency is a deficiency of thiamine, also called vitamin B1, which can develop for several reasons, including alcoholism (common) and a lack of thiamine in the diet. There also are important connections between thiamine deficiency and diabetes because of the role that thiamine plays in the metabolism of sugars. Classically, the simple lack of thiamine in the diet has been associated with certain diets, especially those dominated by polished rice. This does not happen today, in developed countries, due to the enrichment of numerous foods with thiamine, but thiamine deficiency is possible in the setting of the popular gluten-free diet, which avoids whole grains (a good source of thiamine) yet is appropriate, only for those who suffer from celiac disease, but not for everybody else. During pregnancy, your need for thiamine increases, and thiamine deficiency can develop as a complication of hyperemesis gravidarum (HG), a condition that features severe nausea and vomiting, with weight loss and liver problems.

How common is thiamine deficiency during pregnancy?

Thiamine deficiency is rare in non-alcoholics, but the chances of developing it are elevated in those who avoid foods that are abundant in thiamine, such as whole grains, legumes, and breakfast cereals. Nearly all packaged foods that contain grain are enriched with thiamine, but people who avoid gluten are at a particular risk of inadequate thiamine intake because gluten-free foods essentially are the foods that are made without wheat. Consequently, you should not eat gluten-free, unless you have celiac disease. Other factors that put you at risk for thiamine deficiency include HIV/AIDS, bariatric surgery, diuretic medication (medication to increase water excretion through the kidneys). Diabetes type 2, which is characterized by a reduced ability of the body to respond to insulin, entails an increased need for thiamine, so it is both a cause of thiamine deficiency and a condition that thiamine deficiency can exacerbate.

How is thiamine deficiency during pregnancy diagnosed?

Mild thiamine deficiency is very difficult to diagnose because symptoms are mild and not specific to the condition. Consequently, the index of suspicion for thiamine deficiency tends to be very low for non-alcoholics. Hence, doctors have no reason to order tests for levels of thiamine in the blood and urine. As the deficiency worsens, however, various symptoms develop that collectively are characteristic of a disease called beriberi, which is characterized by various symptoms involving both the nervous system and the cardiovascular system. Additionally, various metabolic abnormalities often emerge, including lactic acidosis. The combination of effects provides a hint of possible thiamine deficiency, leading to tests for thiamine levels in blood and urine samples. Most importantly, thiamine deficiency can be assessed by measuring the activity of an enzyme called erythrocyte transketolase (EKTA), which requires thiamine to function, and which is vital to connecting biochemical pathways that break down glucose (blood sugar) to release energy with pathways that build up various biochemical compounds from glucose. Thus, if EKTA activity is low, this supports a diagnosis of thiamine deficiency.

Does thiamine deficiency cause problems during pregnancy?

Symptoms of beriberi include tingling (paresthesia) and loss of sensation (anesthesia) in the hands and feet, breathing difficulty, vomiting, and cardiovascular problems that may include a rapid heartbeat and collection of fluid throughout the body (edema). Ultimately, the cardiovascular effects (known classically as wet beriberi) can lead to heart failure, while the nervous system effects (dry beriberi) can reach the point of two very severe complications. One such complication is called Wernicke encephalopathy (WE). Typically triggered by the administration of intravenous fluids with glucose (sugar), WE is characterized by three neurological abnormalities, all of which occur in most cases: One is the weakness of the muscles that move the eyes (ophthalmoparesis) with rapid, repetitive movement of the eyes back and forth (nystagmus). Another abnormality is the lack of full control of voluntary muscles and coordinated body movements (ataxia), and the third abnormality is confusion. The other neurological complication is Korsakoff syndrome, which is a psychotic disorder that begins with memory loss, followed by what is called confabulation, in which the person unwittingly invents information to fill in the memory gaps. The combination of WE and Korsakoff syndrome is known as Wernicke-Korsakoff syndrome (WKS).

Does thiamine deficiency cause problems for the baby?

Thiamine deficiency increases the risk of adverse outcomes of pregnancy, including spontaneous abortion (miscarriage), fetal death, and stillbirth.

What to consider about taking medications when you are pregnant or breastfeeding:

  • The risks to yourself and your baby if you do not treat the thiamine deficiency
  • The risks and benefits of each medication you use when you are pregnant
  • The risks and benefits of each medication you use when you are breastfeeding

What should I know about using medication to treat thiamine deficiency during pregnancy?

Thiamine deficiency is treated with 50-100 mg of thiamine administered intravenously (IV) and then smaller amounts (such as 10 mg) injected daily intramuscularly (IM) for a week. Thiamine therapy must begin before the woman is given any glucose (dextrose). Otherwise, there is great danger that glucose can trigger the development of WE.

Who should NOT stop taking medication for thiamine deficiency during pregnancy?

Thiamine therapy should continue for a week.

What should I know about choosing a medication for my thiamine deficiency during pregnancy?

It is important to stay in communication with your health care provider as the release of new studies over time can change the outlook on the role of specific medications during pregnancy.

You may find Pregistrys expert reports about the medications to treat this condition here. Additional information can also be found in the sources listed below.

What should I know about taking a medication for my thiamine deficiency when I am breastfeeding?

Like pregnancy, breastfeeding increases your need for thiamine, due to the thiamine needs of the baby. Rather being a risk for a nursing baby, thiamine supplementation is vital to assure that your milk supplies the baby with adequate thiamine. If your doctor determines that your thiamine status is not good, then you may need to feed your infant with formula.

What alternative therapies besides medications can I use to treat my thiamine deficiency during pregnancy?

There is no alternative to thiamine therapy if you are deficient.

What can I do for myself and my baby when I have thiamine deficiency during pregnancy?

Follow the instructions of your physician. If the condition has not advanced to the point of Ko
rsakoff syndrome, then it is reversible with thiamine therapy. If WE is recognized early and treated with thiamine, then your condition can improve dramatically within a matter of days. To lower your risk of developing a thiamine deficiency, take pregnancy vitamin supplements and eat foods that are abundant in thiamine, such as whole grains, legumes, and breakfast cereals (generally, foods containing grains are fortified with thiamin and certain other nutrients). Do not seek out gluten-free foods, unless you have been diagnosed with celiac disease. If you have diabetes, your condition should be evaluated frequently as pregnancy advances.

Resources for thiamine in pregnancy:

For more information about Wernicke encephalopathy during and after pregnancy, contact (800-994-9662 [TDD: 888-220-5446]) or contact the following organizations:

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Last Updated: 19-01-2020
General information

It is very common for women to worry about having a miscarriage or giving birth to a child with a birth defect while they are pregnant. Many decisions that women make about their health during pregnancy are made with these concerns in mind.

For many women these concerns are very real. As many as 1 in 5 pregnancies end in a miscarriage, and 1 in 33 babies are born with a birth defect. These rates are considered the background population risk, which means they do not take into consideration anything about the health of the mom, the medications she is taking, or the family history of the mom or the baby’s dad. A number of different things can increase these risks, including taking certain medications during pregnancy.

It is known that most medications, including over-the-counter medications, taken during pregnancy do get passed on to the baby. Fortunately, most medicines are not harmful to the baby and can be safely taken during pregnancy. But there are some that are known to be harmful to a baby’s normal development and growth, especially when they are taken during certain times of the pregnancy. Because of this, it is important to talk with your doctor or midwife about any medications you are taking, ideally before you even try to get pregnant.

If a doctor other than the one caring for your pregnancy recommends that you start a new medicine while you are pregnant, it is important that you let them know you are pregnant.

If you do need to take a new medication while pregnant, it is important to discuss the possible risks the medicine may pose on your pregnancy with your doctor or midwife. They can help you understand the benefits and the risks of taking the medicine.

Ultimately, the decision to start, stop, or change medications during pregnancy is up to you to make, along with input from your doctor or midwife. If you do take medications during pregnancy, be sure to keep track of all the medications you are taking.