Pregnancy Test: Maternal Nutrition Overwhelms Statistics
The best of intentions sometimes fail. There can be many reasons. According to the Institute of Medicine, almost 60% of all pregnancies are unintended. While many factors contribute, e.g. knowledge about contraceptives, personal and cultural beliefs and behaviors, etc., the reality is that maternal nutritional status during pregnancy is important.
Vitamin D deficiency during pregnancy is linked with low birth weight, neonatal hypocalcemia, poor postnatal growth, bone fragility, and increased risk of autoimmune diseases.
Long-chain polyunsaturated fatty acids (LCPUFA) are essential for brain development, especially the omega-3 LCPUFA docosahexaenoic acid (DHA) which represents 97% of the LCPUFA in the brain. Double-blind, randomized controlled trials (RCT) have demonstrated that maternal LCPUFA DHA status during pregnancy affects the supply of lipids provided to the infant. A supplement of 600 mg DHA daily during pregnancy results in greater gestation duration and infant size.
Bernard and colleagues examined associations between dietary maternal LCPUFA intakes, measured by dietary surveys at 24 and 28 wk gestation, and childhood neurodevelopment at 2 and 3y of age. A total of 2,002 women were enrolled. Based on a 55% participation rate they report a significant negative correlation between high n6:n3 intake and neurodevelopment, assessed by the Communicative Development Inventory (CDI). However, the results (Table 4) need to be put in perspective. With 4 different measurements of childhood neurodevelopment, e.g. CDI, ASQ, PMT-5, etc., and 20 variables, e.g. n6 LCPUFAs, n3LCPUFAs, n6:n3 ratios, and individual fatty acids, etc., the authors found 2 significant correlation and 1 significant interaction (breastfed vs never-breast fed). This means 3 significant observations among 80 (=20x4), <4% of comparisons were significant. As Dr Gerard Dallal, writes, there are statistical risks in making multiple comparisons.
It is difficult to draw insights from a paper using maternal dietary records on childhood development years later. However, it isn’t difficult to conclude that nutrients essential for growth and development, such as folic acid, vitamin D, and DHA, during pregnancy and the first 2 years will have a profound effect on child development.
De-Regil LM, Fernandez-Gaxiola AC, Dowswell T, Pena-Rosas JP. Folic acid supplements before conception and in early pregnancy (up ot 12 weeks) for the prevention of birth defects. 2010 Cochrane Database of Systematic Reviews doi:10.1002/14651858.CD007950.pub2
Linaberry AM, Johnson KJ, Ross JA. Childhood cancer incidence trends in association with US folic acid fortification (1986-2008). 2012 Pediatrics doi:10.1542/peds.2011-3418
Carlson SE, Colombo J, Gaajewski BJ, Gustafson KM, Mundy D, Yeast J, Georgieff MK, Markley LA, Kerling EH, Shaddy DJ. DHA supplementation and pregnancy outcomes. 2013 Am J Clin Nutr doi:10.3945/ajcn.112.050021
Mulligan ML, Felton SK, Riek AE, Bernal-Mizrachi C. Implications of vitamin D deficiency in pregnancy and lactation. 2010 Am J Obstet Gynecol doi:10.1016/j.ajog.2009.09.002
Bernard JY, De Agostini M, Forhan A, de Lauzon-Guillain B, Charles M-A, Heude B, EDEN Mother-Child Cohort Study Group. Dietary n6:n3 fatty acid ration during pregnancy is inversely associated with child neurodevelopment in the EDEN mother-child cohort. 2013 J Nutr doi:10.3945/jn.113.178640