Protein and Amino Acid Requirements during Pregnancy

Abstract

Protein forms an essential component of a healthy diet in humans to support both growth and maintenance. During pregnancy, an exceptional stage of life defined by rapid growth and development, adequate dietary protein is crucial to ensure a healthy outcome. Protein deposition in maternal and fetal tissues increases throughout pregnancy, with most occurring during the third trimester. Dietary protein intake recommendations are based on factorial estimates because the traditional method of determining protein requirements, nitrogen balance, is invasive and undesirable during pregnancy. The current Estimated Average Requirement and RDA recommendations of 0.88 and 1.1 g · kg(-1) · d(-1), respectively, are for all stages of pregnancy. The single recommendation does not take into account the changing needs during different stages of pregnancy. Recently, with the use of the minimally invasive indicator amino acid oxidation method, we defined the requirements to be, on average, 1.2 and 1.52 g · kg(-1) · d(-1) during early (∼16 wk) and late (∼36 wk) stages of pregnancy, respectively. Although the requirements are substantially higher than current recommendations, our values are ∼14-18% of total energy and fit within the Acceptable Macronutrient Distribution Range. Using swine as an animal model we showed that the requirements for several indispensable amino acids increase dramatically during late gestation compared with early gestation. Additional studies should be conducted during pregnancy to confirm the newly determined protein requirements and to determine the indispensable amino acid requirements during pregnancy in humans.

The potential of a simple egg to improve maternal and child nutrition

“…A single estimated average requirement for protein covers all pregnancy, which does not take into consideration changing needs as a pregnancy progresses. Protein requirements may be 14% to 18% greater than the current recommendation according to recent research (Elango & Ball, ). Eggs are also an important source of essential fatty acids.…”

Lysine Requirements of Healthy Pregnant Women are Higher During Late Stages of Gestation Compared to Early Gestation

“…This paucity of amino acid requirement data is due to numerous ethical and practical issues of using the traditional nitrogen balance design to study a vulnerable population, such as pregnant women (8). Recent research has focused instead on applying novel tracer techniques involving the use of stable isotopes, such as the IAAO method, in the hope of establishing requirement estimates in various physiological conditions and vulnerable populations (9,10).…”

Hyperornithinemia‐hyperammonemia‐homocitrullinuria syndrome in pregnancy: Considerations for management and review of the literature

“…Protein guidelines for pregnancy in normal woman vary between DRI of 1.1 g/kg/d (for second half of pregnancy) 7 and 1.2-1.52 g/kg/d for early to late gestation. 8 In pregnant women with urea cycle disorders, who are known to be averse to dietary protein often complicated with anorexia and nausea, and have noncompliance/inability to take ammonia scavenging medications, protein intake needs to be closely monitored to ensure normal amino acid profiles, prevent catabolism/metabolic decompensation, and avoid hyperammonemia. This is balanced with ensuring adequate nonprotein calories.…”