The first three years of life are a period of rapid brain growth. Vitamin B12 is necessary for normal cell division and differentiation, as well as for the development and myelination of the central nervous system. Poor vitamin B12 status in pregnant mothers in resource-poor settings puts them at risk for poor growth and neurodevelopment in their infants. Brain development starts from conception, and pregnancy is a period of rapid growth and development for the brain. The first three years of life are a critical period for brain development.
Discussion
A recent study concluded that there is a lack of knowledge on the potential benefits of vitamin B12 on pregnancy and perinatal outcomes.21 This proposed study seeks to measure the effect of vitamin B12 supplementation from early pregnancy through 6 months postpartum on early neurodevelopment and growth in 800 Nepalese infants at 6 and 12 months. Our results can be used to inform both regional dietary guidelines for Nepalese and South Asian pregnant women.
There is no commercial funding for this work This study has been approved by National Health and Research Council, Nepal (NHRC 253/2016) and Regional Committee for Medical and Health Research Ethics of Western Norway (2016/1620/REK vest). Investigators who have contributed to the conceptualizing, conducting, as well as being involved in the data analyses and manuscript writing will be eligible for authorship and be responsible to share outcomes with different stakeholders through publications and workshops. The results from this study may support new dietary guidelines for Nepalese and possibly South Asian pregnant women that can lead to improved pregnancy outcomes, neurodevelopment and cognitive functioning in children. There is no commercial funding for this work.
Strengths and limitations of this study
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This trial will be testing the effects of maternal vitamin B12 supplementation during pregnancy and postpartum on early child development and growth. It is a large-scale, randomized controlled trial.
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We are using a variety of tools to comprehensively assess neurodevelopment in this population. These tools have all been used before in similar populations.
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There is a chance that not all women will have poor vitamin B12 status, which could mean that this study won't have enough power to accurately detect any important differences.
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The primary outcomes of the study will be measured when the children are 6 and 12 months old, however the benefits of improved vitamin B12 status in the mother might not be measurable in the children until later childhood.
Background
Cobalamin (vitamin B12) deficiency is common in many low and middle-income countries.1 2 This is not surprising as the main source of vitamin B12 is animal source foods, which are expensive and for cultural and religious reasons often not eaten at all. In several studies of women and children, we have demonstrated that poor vitamin B12 status is common in South Asia.3–5 There is also compelling evidence that vitamin B12 deficiency occurs frequently during pregnancy,2 6 7 and case studies have demonstrated harmful effects of severe vitamin B12 deficiency on the developing infant brain.8 9 The consequences of mild or subclinical vitamin B12 deficiency are less clear but it has been shown to be associated with decreased cognitive performance in both the elderly and children.10–13 Three randomized controlled trials (RCT) have measured the effect of vitamin B12 supplementation on neurodevelopment in children: In a Norwegian trial, an intramuscular injection of B12 substantially improved the motor development in 6-week-old infants after 1 month,14 another intervention study in low birthweight children recently confirmed these findings.15 The infants in these studies had evidence of suboptimal vitamin B12 status, but none was severely deficient. We found a beneficial effect of vitamin B12 supplementation for 6 months on neurodevelopment in young North Indian children.16 In this study, where the children were supplemented daily with two recommended daily allowances (RDA) for 6 months, the effect of vitamin B12 supplementation was more apparent in children who had evidence of vitamin B12 deficiency at the start of the study. Many low and middle-income countries have a high prevalence of cobalamin (vitamin B12) deficiency.1 2 This is not surprising, as the main source of vitamin B12 is from animal-based foods, which are expensive and often not eaten at all for cultural and religious reasons. A study conducted in North India found that children who were supplemented with two recommended daily allowances (RDA) of vitamin B12 for six months had improved neurodevelopment,16 with the effect being more apparent in those who were deficient in vitamin B12 at the start of the study.
During pregnancy, vitamin B12 is exchanged between the mother and fetus.18 Infants born to mothers with adequate vitamin B12 levels usually have enough stores of the vitamin to last several months. However, babies born to mothers who are deficient in vitamin B12 are susceptible to deficiency at an early age.19
Maternal vitamin B12 deficiency has been associated with increased risk of common pregnancy complications, including spontaneous abortion, low birth weight, intrauterine growth restriction and neural tube defects.20–22 Children born to vitamin B12-deficient women are at increased risk for adverse health outcomes, including developmental abnormalities and anaemia.9 23 In a recent RCT in Bangalore, India, daily maternal vitamin B12 supplementation (50 µg/day) during pregnancy through 6 weeks postpartum substantially improved maternal vitamin B12 status and increased breast milk and infant plasma vitamin B12 concentrations.24 In this study, the proportion of children being born small for gestational age was lower in the vitamin B12 group than in the placebo group (25% vs 34%); however, no difference was found in neurodevelopment in infants at 9 months of age.25 Similar improvements in vitamin B12 status were found among Bangladeshi mothers and infants when supplemented with 250 µg of vitamin B12 from 11 to 14 weeks of pregnancy through 3 months postpartum.26 In this study, women who were randomized to receive vitamin B12 also had an improved immune response to the pandemic influenza A (H1N1) vaccine.
During the first 1000 days after conception, brain growth is rapid and myelination of the brain occurs. This makes the brain susceptible to influences from the environment. Vitamin B12 deficiency has been associated with demyelination and brain atrophy in infants. It is not known what maternal vitamin B12 deficiency does to early brain myelination, neurodevelopment and cognitive function.
Hypothesis to be tested
In Nepalese women, giving 50 micrograms of vitamin B12 every day from early pregnancy, no later than week 15, and until 6 months after the baby is born, improves the baby's physical growth, as well as the baby's scores on tests of cognitive skills, language skills, and/or motor skills.
Specific objectives
Primary objectives
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The aim of the study is to improve cognitive, language and motor scores of the Bayley-III by giving 50 μg of vitamin B12 to the mother every day from early pregnancy until 6 months postpartum.
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The purpose of the study is to see if giving 50 micrograms of vitamin B12 to pregnant women from early pregnancy until 6 months after they give birth will improve their infant's z-scores for length, weight, and weight-for-length at 12 months.
Secondary objectives
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The purpose of this study is to see if giving vitamin B12 to pregnant women starting early in their pregnancy and continuing for six months after their baby is born can improve the mother's and baby's levels of hemoglobin. The study will also look at the effect of the mother's and baby's hemoglobin levels on the baby's cognitive development at six and twelve months old.
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We want to know if giving vitamin B12 to pregnant women from early pregnancy until 6 months after they give birth will help improve the cognitive function of their infants, as measured by the Bayley-III test at 24 months old.
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To improve development, daily maternal administration of vitamin B12 should begin from early pregnancy and continue until 6 months postpartum, as measured by the Ages and Stages Questionnaire, Third Edition (ASQ-3). This should be continued until the child is 6-12 months old.
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The purpose of this study is to see if giving vitamin B12 to mothers from early pregnancy to 6 months after birth will improve their infants' motor function as measured by the Test of Infant Motor Performance at 45 days.
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The researchers wanted to see if giving vitamin B12 to pregnant women starting early in their pregnancy and continuing until six months after they give birth would reduce the risk of having a complicated delivery.
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The purpose of this study is to determine whether taking vitamin B12 during pregnancy reduces the risk of having a baby that is small for gestational age.
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The efficacy of vitamin B12 on growth and development should be explored in various subgroups.
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To investigate whether daily maternal administration of vitamin B12 from early pregnancy until 6 months postpartum has an effect on sleep and activity patterns of infants, researchers need to measure changes in these patterns.
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The effects of daily maternal administration of vitamin B12 from early pregnancy until 6 months postpartum on heart rate variability will be measured.
Methods
Study setting
The study site is Bhaktapur, located 14 kilometers east of Kathmandu. Bhaktapur is an ancient city, known for its traditional temples and buildings, and is listed as a UNESCO World Heritage site. Bhaktapur is mostly Hindu and Buddhist, though it is a mixed community. Bhaktapur is primarily an agricultural community located at 1400 meters above sea level. The population is predominantly Newar, though there are migrant workers from other ethnic groups who work in the city's carpet factories. The climate in Bhaktapur is humid subtropical, with a wet and hot season from May to August, and a dry and cool season from October to March. The staple food in this area is rice, and the way it is eaten changes depending on the season, how much work there is in the fields, and what other foods are available. A lot of different local green leafy vegetables are eaten mainly in the winter and spring.
Eligibility criteria
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Pregnant women aged 20 to 40 who are in early pregnancy, no later than 15 weeks pregnant.
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People who live in Bhaktapur municipality and the areas surrounding it in Bhaktapur district.
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availability of informed consent.
Exclusion criteria
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taking dietary or multivitamin supplements containing vitamin B12;
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There are certain chronic diseases that people are currently being treated for, such as tuberculosis, diabetes, hypertension, hypo or hyperthyroidism, pernicious anaemia, Crohn’s disease, and the use of anticonvulsant drugs.
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Severe anemia is defined as a hemoglobin concentration less than 7 g/dL. Hemoglobin concentration will be measured immediately after blood is collected at enrollment, using the HemoCue system.
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People suffering from conditions that require treatment with vitamin B12, such as pernicious anaemia, and strict vegans, may be at risk for vitamin B12 deficiency.
Intervention
GC Rieber Compact produces the supplements. The vitamin and placebo tablets are the same in composition, taste, smell, and appearance, except for the cyanocobalamin content. The compositions of the tablets follow the recipe of the commercial product ‘Seven OceanS Emergency Ration.' Each daily dose (placebo or 50 µg vitamin B12) also contains 31 kcal from the 6.95 g vehicle, which mainly consists of dextrose and palm oil. The first dose of supplementation will be given by research staff at the hospital. Mothers will then be instructed to properly store the supplements and consume them every day, preferably in the morning. During the weekly visits, our research staff will record consumption of the supplement during the last 7 days, including iron, folic acid, and calcium, and also count the amount of remaining supplements. The gynecologists' conducting the study will check to make sure the participants are taking their supplements as prescribed during their visits to the hospital. Additionally, supervisors for the study will randomly select days to visit the participants' mothers at home to check whether they are complying with the supplement regimen.
Cointervention
Folic acid (0.4 mg) will be given to all pregnant women for the first 2 months of pregnancy, followed by iron (60 mg elemental iron) and calcium supplements (500 mg) until 45 days after delivery, per WHO guidelines.30
Recruitment procedure, confirmation of pregnancy and assessment of gestational age
After delivery, the delivery and birth outcomes are registered We will be using a hospital and community-based surveillance system to identify pregnant mothers (figure 1). We have records of newly married couples in the study area that are updated quarterly. We will be collecting information on pregnancies monthly through household surveys or phone calls. Women with a history of interrupted menstruation cycles or pregnancies detected by standard human chorionic gonadotropin kits will be screened in the hospital. In these women, pregnancy and gestational age will be estimated through ultrasonography (USG). Follow-up USG will be performed between 18 and 22 weeks for anomalies scanning. After delivery, the delivery and birth outcomes will be recorded.
Discussion
This study proposes to measure the effect of vitamin B12 supplementation from early pregnancy through 6 months postpartum on neurodevelopment and growth in Nepalese infants at 6 and 12 months. This trial will add to the knowledge on the potential beneficial effects of vitamin B12 on pregnancy and perinatal outcomes. The results from this study may contribute to necessary updates to WHO guidelines on antenatal care for a positive pregnancy experience.
