Life Cycle Nutrition: Pregnancy

Life Cycle Nutrition: Pregnancy

• Pregnancy nutrition is crucial for fetal development and maternal health
• Adequate nutrition prior to conception supports successful implantation and early placental growth
• The placenta facilitates vital functions including gas exchange, waste removal, and nutrient exchange between mother and fetus
• The maternal blood provides oxygen and nutrients to the fetus, and removes waste products
• Fetal blood vessels are closely intertwined with maternal vessels in the placenta, enabling transfer of substances without mixing

Stages of Embryonic and Fetal Development

• Fertilization occurs when a sperm fertilizes an egg forming a zygote; this zygote is small initially
• After implantation, the placenta develops to nourish the embryo
• The embryo grows in size and develops crucial organs and tissues, during critical weeks
• A fetus develops rapidly, increasing in size and weight by multiple orders of magnitude, over many weeks
• Critical periods of fetal growth are susceptible to nutrient deficiencies, which can cause irreversible damage to organs and have a lasting impact on the child's wellbeing.

Folate Availability and Neural Tube Defects

• Neural tube closure occurs early in gestation, typically before the 6th week
• Inadequate folate intake during this critical period can lead to neural tube defects like spina bifida
• Folic acid fortification has reduced the incidence of these defects.

Body Weight & Weight Gain in Pregnancy

• Ideal weight gain during pregnancy varies based on BMI prior to conception
• The recommended range for healthy weight gain in one pregnancy is around 11.5 - 16 kg (25 - 35 lbs).
• Low or excessively high pre-pregnancy BMI is associated with adverse outcomes (or complications).

Maternal Gestational Weight Gain (GWG)

• Maternal gestational weight gain varies by trimester, with differences in rate and recommendations depending on pre-pregnancy BMI category.
• Canadian GWG Recommendations have specified ranges of total weight gain according to different BMI categories (underweight, normal, overweight and obese). This weight gain is based on stages of pregnancy
• An incorrect weight gain amount is associated with risk of complications for both mother and child.

Risks Associated with Preterm or Low Birth Weight

• Preterm birth and low birth weight are associated with an increased risk of short-term mortality, poor long-term outcomes like childhood/adult obesity and problems with cognition
• These are associated with risk of health and developmental issues (mental, physical).

Risks Associated with High Birth Weight

• High birth weight or LGA (Large for Gestational Age) is linked with complications following birth and increased risk of childhood and adult obesity
• This gestational weight gain can lead to difficult birthing processes and long-term associated health issues.

High Risk of Complications During Pregnancy

• Factors such as obesity lead to a range of difficulties for both the mother and the developing fetus (e.g., hypertension, gestational diabetes, cesarean section).
• Various complications and adverse outcomes for maternal and child health can result from obesity during pregnancy.

Factors Contributing to Low Birth Weight

• Low weight during pregnancy, inadequate gestational weight gain, smoking, and poor maternal nutrition are among the causes of low birth weight.
• Poor maternal nutrition, smoking, and alcohol consumption while pregnant contribute to low birth weight
• Other maternal factors such as diseases or heredity can also increase rates of low birth weight.

Global Concerns of Maternal Underweight and Malnutrition

• Infant malnutrition and low birth rates are associated with global concerns for survival and development
• Factors such as poor maternal nutrition, pre-existing deficiencies, inadequate breast feeding, and other complications may increase the rate of low birth weights and malnutrition.

Additional Energy Requirements During Pregnancy

• Increased energy (calorie) needs vary by trimester, with no additional needed during the first trimester, an increase of 340kcal during the second trimester, and 450kcal during the final trimester
• The specific needs of the mother and the developing baby change during the different trimesters.

Additional Protein Requirements During Pregnancy

• Additional protein is needed during pregnancy (beyond the recommended daily allowance) and varies based on weight.
• The additional protein needs to support growth, development, and health of both mother and child.

Dietary Fat Intake During Pregnancy

• A suitable fat intake is needed during pregnancy, however, excessive fat is also linked to adverse outcomes
• DHA and arachidonic acid are important for fetal development, but careful attention must be paid to environmental contamination levels
• It is recommended to include fish in the maternal diet (but the amount needs to be monitored with caution).

General Diet/Food Advice For Pregnancy

• Limit caffeine intake to less than 300 mg/day
• Avoid uncooked animal protein, smoked fish, raw sushi, raw eggs, and raw meat, as well as non-nutritive sweeteners.
• Avoid excessive vitamin and mineral supplements
• Listeriosis (foodborne illness) risk increases during pregnancy.

Alcohol and Fetal Growth

• Alcohol consumption poses serious risks to the developing fetus particularly during the first trimester, limiting oxygen and nutrient delivery for development; and impacting cell growth during critical periods.
• Fetal Alcohol Syndrome/Spectrum Disorder (FAS/FASD) is linked with irreversible brain damage, growth retardation, and organ defects.

Exercise During Pregnancy

• Physical activity, especially low-impact exercises, are recommended
• Exercise aids in labor, reduces discomfort, and lowers risks such as gestation diabetes
• Check with a medical professional prior to initiating any new exercise regime or activity.