Despite a 48.2% prevalence of vitamin B12 deficiencies in the sample, the report did not note an association between B12 and LBWs.
The researchers, from Bengaluru, India, and the Netherlands, highlights the importance of their findings: “There is a growing need to counsel pregnant women on the right diets to ensure adequate vitamins B12 and B6 and folate are consumed.”
“It is essential to conduct large-scale studies investigating the combined role of nutrients involved in OCM to guide the development of intervention. Such steps can ensure intake of folate and micronutrients during preconception and pregnancy to prevent low birth weight,” they stress.
There is a great prevalence of infants born with a LBW, with a UNICEF report stating it had affected 20 million children in 2015. This is especially prominent in low- and middle-income countries with the highest annual figures in Asia, representing a major public health issue in India.
LBWs have been linked to significant health issues in the long-term, increasing risk of metabolic complications, cardiovascular disease and all-cause mortality. The mother’s nutrition plays a key part in the occurrence of LBW, with the B-vitamins of B12, folate and B6 noted to be particularly critical due to their involvement in metabolism and DNA synthesis.
Following this, previous studies have demonstrated a strong association between LBW occurrence and such micronutrients and folate levels, in comparison energy and protein intakes. Yet, there is still a limited understanding with regards to this association.
In addition, it has been established that there are highly prevalent levels of vitamin B12 in India, which has been hypothesised to potentially result from the high population of vegetarians. There is a general lack of further nutrient deficiency data in this region.
Considering this, the researchers sought to investigate this relationship between micronutrient status and birth outcomes, specifically looking into vitamin B6, B12, and folate levels during pregnancy.
The study utilised participants from the ongoing ‘Maternal Antecedents of Adiposity and Studying the Transgenerational Role of Hyperglycaemia and Insulin’ (MAASTHI) cohort, with 300 pregnant women aged between 18 and 45 years old.
Socioeconomic and anthropometric data was obtained, paired with collated blood samples between weeks 24 and 32 of gestation. Levels of B6, B12, folate, homocysteine, and methylmalonic acid (MMA) levels were analysed.
It was reported that there were significantly low levels of vitamin B12 in 48.5% of the population of women studied, as well as low levels of folate in 42%. 10.4% demonstrated low levels of vitamin B6.
Following this, the researchers established a significant relationship between both B6 and folate and birth weight, with folate deficiencies resulting in a doubled risk of low birth weight.
“Our findings reveal a significant association between vitamin B6 levels and impaired folate levels with low birth weight,” the report concludes, continuing to draw attention to a study highlighting the improvement of birth weights following the associated supplementation. The findings shed light onto the possible importance of considering such interventions for regions with prevalent deficiencies.
Following that lack of association between vitamin B12 and birth weights, the researchers hypothesise: “Considering the coenzymatic role of B12, it may not be as influential as nutrients such as folate that serve as a methyl donor in one-carbon metabolism.”
The scientists stress the importance of long term RCTs to further investigate this association, to ultimately improve the long-term health outlooks for infants with LBWs.
“Vitamin B6 Levels and Impaired Folate Status but Not Vitamin B12 Associated with Low Birth Weight: Results from the MAASTHI Birth Cohort in South India”
by R. Deepa, Siddhartha Mandal, Onno C. P. Van Schayck and Giridhara R. Babu