Maternal micronutrient status should be viewed as a continuum across the pre-conception, pregnancy, and lactation period. From adolescence onwards, a woman’s nutrient needs are higher, yet the fulfillment of her nutrition requirements is more at risk than that of a man. As a girl, adolescent, pregnant woman, or young mother – a woman’s access to nutritious foods is limited by socio-cultural inequities.
The development and growth of a fetus require additional energy and nutrients, hence their requirements during pregnancy are increased. The same is true for breastmilk production and increased nutrient requirements of lactating mothers. Without compensatory dietary intake, the mother’s nutrient stores risk being depleted.
Additional energy costs of pregnancy are around 300-390 kcal/day [11, 12]. Additional energy costs of lactation are estimated to be around 630-650 kcal/day [13, 14].
Micronutrient needs are also increased during pregnancy and lactation, though levels depend on the specific mineral or vitamin. RDAs for several of the B-vitamins for instance are 25-30% higher in pregnancy and up to 50 % higher in lactation than for non-pregnant non-lactating women.
Women are especially vulnerable to anemia. For women aged 12-49, iron is needed to make the new blood that replaces the blood lost during each menstrual period. Women who are not consuming enough iron-rich foods are at risk for developing anemia and may need supplementation to prevent low iron levels.
While iron and folate receive the most attention, multiple micronutrient deficiencies occur simultaneously when diets are poor. Pregnant and breastfeeding women are even more vulnerable to nutritional deficiencies due to higher needs to support the growth and development of their baby and harmful consequences of deficiencies on pregnancy outcomes.[15]
For instance, iodine is essential in the first 16 weeks of pregnancy; without it, miscarriages and stillbirths are more common, and the development of a baby’s brain and healthy cognition is compromised. Poor maternal B-vitamin status may be a major global cause of homocysteinemia and poor pregnancy outcomes. Vitamin D deficiencies are associated with poor fetal and infant skeletal growth and mineralization, and poor infant tooth mineralization. While women need 2.5 times more iron than men on average, this requirement increases further during pregnancy.[16]
References
11. Hytten, F.E. 1980. Nutrition. Pp. 163–192 in F. Hytten, editor; and G. Chamberlain, editor. , eds. Clinical Physiology in Obstetrics. Blackwell Scientific Publications, Oxford.
12. Most, J., Dervis, S., Haman, F., Adamo, K. B., & Redman, L. M. (2019). Energy Intake Requirements in Pregnancy. Nutrients, 11(8), 1812.https://doi.org/10.3390/nu11081812
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6723706/
13. Joop M.A. van Raaij, C.M. Schonk, S.H. Vermaat-Miedema, M. E. M. Peek. Energy cost of lactation, and energy balances of well-nourished Dutch lactating women: Reappraisal of the extra energy requirements of lactation. April 1991, American Journal of Clinical Nutrition 53(3):612-9. DOI:10.1093/ajcn/53.3.612
14. Nancy F Butte1,* and Janet C King2 (2005). Energy requirements during pregnancy and lactation. Public Health Nutrition: 8(7A), 1010–1027 DOI: 10.1079/PHN2005793 http://elactancia.org/media/papers/DietaNecesidadesBF-PubHealNut2005.pdf
15. Keats EC, Haider BA, Tam E, Bhutta ZA. Multiple‐micronutrient supplementation for women during pregnancy. Cochrane Database of Systematic Reviews 2019, Issue 3. Available here (Accessed 17 February 2022).
16. Lindsay H Allen, Multiple micronutrients in pregnancy and lactation: an overview, The American Journal of Clinical Nutrition, Volume 81, Issue 5, May 2005, Pages 1206S–1212S, https://doi.org/10.1093/ajcn/81.5.1206