From the Guidelines
Thiamine (vitamin B1) plays a crucial role in pregnancy, particularly in preventing complications such as Wernicke's encephalopathy and beriberi, and its recommended daily intake is 1.4 mg for pregnant women.
Importance of Thiamine in Pregnancy
Thiamine is an essential nutrient that should be obtained through a balanced diet including whole grains, pork, fish, beans, and fortified foods like breakfast cereals. Most prenatal vitamins contain adequate thiamine, typically 1.5-3 mg per dose, so additional supplementation is usually unnecessary unless specifically prescribed by a healthcare provider 1.
Recommendations for Thiamine Intake
The daily dose recommendation for thiamine supplementation during pregnancy is >12 mg, as suggested by the consensus recommendations for periconception, antenatal, and postnatal care 1. However, for women with hyperemesis gravidarum, a dosage of 100 mg daily for a minimum of 7 days, followed by a maintenance dosage of 50 mg daily, is recommended to prevent refeeding syndrome and Wernicke encephalopathy 1.
Key Considerations
It is essential to note that thiamine deficiency during pregnancy is rare in developed countries but can lead to serious complications, including Wernicke's encephalopathy, beriberi, and potential adverse effects on fetal development. Women with hyperemesis gravidarum, alcohol use disorder, or malabsorption conditions may require higher doses of thiamine, and it is crucial to consult with a healthcare provider before starting any supplement during pregnancy to ensure it's appropriate for specific needs. Thiamine is water-soluble and generally considered safe during pregnancy, with excess amounts excreted in urine.
Summary of Findings
In summary, thiamine is a vital nutrient during pregnancy, and its recommended daily intake is 1.4 mg for pregnant women. While most prenatal vitamins contain adequate thiamine, women with hyperemesis gravidarum or other conditions may require higher doses, and it is essential to consult with a healthcare provider before starting any supplement. The evidence from recent studies, including the 2024 study published in Gastroenterology 1, highlights the importance of thiamine in preventing complications during pregnancy.
From the FDA Drug Label
Studies in pregnant women have not shown that thiamine hydrochloride increases the risk of fetal abnormalities if administered during pregnancy. If the drug is used during pregnancy, the possibility of fetal harm appears remote. Because studies cannot rule out the possibility of harm however, thiamine hydrochloride should be used during pregnancy only if clearly needed The role of Thiamine (Vitamin B1) in pregnancy is to be used only if clearly needed, as studies have not shown an increased risk of fetal abnormalities, but cannot completely rule out the possibility of harm 2, 3.
- Key points:
- Thiamine hydrochloride may be used during pregnancy if clearly needed
- The possibility of fetal harm appears remote, but cannot be completely ruled out
- Studies have not shown an increased risk of fetal abnormalities with thiamine hydrochloride use during pregnancy
From the Research
Role of Thiamine in Pregnancy
Thiamine, also known as Vitamin B1, plays a crucial role in pregnancy due to its involvement in various metabolic processes. The following points highlight its importance:
- Thiamine is essential for glucose oxidation, insulin production by pancreatic beta-cells, and cell growth 4.
- Approximately 50% of women develop a biochemical thiamine deficiency during pregnancy, while the thiamine status falls but remains within normal limits in most other women 4.
- Thiamine supplementation during pregnancy may improve glucose tolerance and stimulate intra-uterine growth, thereby preventing low birth weight 4.
Thiamine Deficiency in Pregnancy
Thiamine deficiency can have severe consequences during pregnancy, including:
- Varied manifestations such as thiamine deficiency-related neuropathy, high-output heart failure, heart failure with reduced ejection fraction, Wernicke's encephalopathy, gastric beriberi, and thiamine-responsive acute pulmonary hypertension 5.
- Increased risk of low birth weight, cardiovascular disease, and diabetes mellitus in later life 4.
- Poor perinatal outcomes, including early infant death 6.
Prevention and Treatment of Thiamine Deficiency
Prevention and treatment of thiamine deficiency are crucial to avoid its consequences:
- Thiamine supplementation can be a safe preventive measure during pregnancy 4.
- Early recognition of clinical features and thiamine therapy can be life-saving 5.
- Treatment with thiamine is safe and effective, with dosing guidelines varying widely 7.
- Prevention efforts depend on local and regional circumstances, including dietary diversification, food fortification, and/or supplementation of children and women at risk 7.
Prevalence of Thiamine Deficiency
The prevalence of thiamine deficiency varies by region:
- Thiamine deficiency is common in many parts of Asia and Africa, affecting up to a third or more of children and women of child-bearing age 7.
- A high prevalence of thiamine deficiency occurs in pregnant women in areas endemic for thiamine deficiency, such as Kashmir 6.
- Low thiamine status is associated with poor nutritional status as well as poor perinatal outcomes 6.