🍼Lifecycle Nutrition Unit 2 – Preconception and Pregnancy Nutrition

Key Nutritional Concepts

• Macronutrients provide energy and include carbohydrates, proteins, and fats
  • Carbohydrates are the body's primary energy source and include sugars, starches, and fiber (whole grains, fruits, vegetables)
  • Proteins are essential for growth, repair, and maintenance of tissues and consist of amino acids (lean meats, poultry, fish, legumes)
  • Fats provide energy, support cell membrane structure, and aid in the absorption of fat-soluble vitamins (healthy fats include avocados, nuts, seeds, olive oil)
• Micronutrients are vitamins and minerals required in smaller amounts for various bodily functions
  • Vitamins are organic compounds that support immune function, vision, bone health, and energy metabolism (vitamin A, B vitamins, vitamin C, vitamin D)
  • Minerals are inorganic elements that play crucial roles in bone formation, fluid balance, and enzyme function (calcium, iron, magnesium, potassium)
• Balanced diet includes a variety of nutrient-dense foods from all food groups to meet nutritional needs
• Nutrient density refers to the amount of nutrients per calorie in a food
  • Nutrient-dense foods provide substantial amounts of vitamins, minerals, and other beneficial compounds with relatively few calories (leafy greens, berries, lean proteins)
• Caloric balance is the relationship between energy intake from food and energy expenditure through physical activity and bodily functions
  • Maintaining a balanced caloric intake is essential for achieving and maintaining a healthy weight

Preconception Nutrition

• Preconception nutrition focuses on optimizing maternal health and nutrient stores before pregnancy
• Folic acid supplementation of 400-800 mcg per day is recommended at least one month before conception to reduce the risk of neural tube defects
• Adequate iron intake and stores are crucial to prevent anemia and support fetal development
  • Iron-rich foods include lean red meat, poultry, fish, legumes, and fortified cereals
• Maintaining a healthy weight before pregnancy reduces the risk of complications such as gestational diabetes and preeclampsia
• Consuming a balanced diet with a variety of nutrient-dense foods ensures adequate intake of essential vitamins and minerals
• Limiting alcohol consumption and avoiding smoking and illicit drugs improve fertility and reduce the risk of adverse pregnancy outcomes
• Regular physical activity before pregnancy promotes healthy weight management and cardiovascular health

Physiological Changes During Pregnancy

• Increased blood volume by approximately 50% to support fetal growth and development
  • Plasma volume increases more than red blood cell mass, leading to physiological anemia
• Cardiac output increases by 30-50% to accommodate increased blood volume and fetal circulation
• Respiratory changes include increased tidal volume and minute ventilation to meet increased oxygen demands
• Gastrointestinal changes such as reduced motility and increased transit time can cause constipation and heartburn
• Renal function adapts to handle increased blood flow and filtration, leading to increased urinary frequency
• Weight gain during pregnancy is essential for fetal growth and development
  • Recommended weight gain varies based on pre-pregnancy BMI (body mass index)
• Hormonal changes, such as increased levels of progesterone and relaxin, contribute to physiological adaptations

Nutritional Needs During Pregnancy

• Energy requirements increase by approximately 340-450 additional calories per day in the second and third trimesters to support fetal growth and maternal tissue development
• Protein needs increase by 25 grams per day to support fetal tissue development and maternal tissue expansion
  • Adequate protein intake is crucial for proper fetal brain development and growth
• Folate requirements increase to 600 mcg per day to support rapid cell division and prevent neural tube defects
• Iron needs increase to 27 mg per day to support increased maternal blood volume and fetal iron stores
  • Iron deficiency anemia during pregnancy can lead to preterm birth and low birth weight
• Calcium requirements remain at 1000 mg per day, but absorption efficiency increases to meet fetal skeletal development needs
• Vitamin D needs increase to 600 IU per day to support calcium absorption and fetal bone development
• Omega-3 fatty acids, particularly DHA (docosahexaenoic acid), are essential for fetal brain and eye development
  • Pregnant women should consume 8-12 ounces of low-mercury fish per week or consider DHA supplements

Common Pregnancy-Related Nutrition Issues

• Nausea and vomiting, particularly in the first trimester, can affect nutrient intake and lead to dehydration
  • Strategies to manage nausea include eating small, frequent meals, avoiding strong odors, and consuming ginger or vitamin B6 supplements
• Heartburn and acid reflux are common due to reduced lower esophageal sphincter tone and increased intra-abdominal pressure
  • Avoiding large meals, staying upright after eating, and consuming smaller, more frequent meals can help alleviate symptoms
• Constipation can occur due to decreased gastrointestinal motility and increased water absorption
  • Increasing fiber intake, staying hydrated, and engaging in regular physical activity can promote regular bowel movements
• Gestational diabetes mellitus (GDM) is a form of diabetes that develops during pregnancy and can affect fetal growth and development
  • Managing GDM involves monitoring blood glucose levels, following a balanced diet, and engaging in regular physical activity
• Pica, the craving and consumption of non-food items, can occur during pregnancy and may indicate nutrient deficiencies
  • Iron deficiency anemia is often associated with pica, and addressing nutrient deficiencies can help manage these cravings

Dietary Recommendations and Meal Planning

• Consume a variety of nutrient-dense foods from all food groups to meet increased nutritional needs
  • Include whole grains, fruits, vegetables, lean proteins, and healthy fats in each meal
• Limit intake of high-mercury fish (shark, swordfish, king mackerel) to reduce fetal exposure to neurotoxins
• Avoid raw or undercooked meats, poultry, eggs, and unpasteurized dairy products to reduce the risk of foodborne illnesses
• Limit caffeine intake to less than 200 mg per day, as excessive consumption may increase the risk of miscarriage and low birth weight
• Plan meals and snacks to ensure consistent nutrient intake throughout the day
  • Eating smaller, more frequent meals can help manage nausea and heartburn
• Consider working with a registered dietitian to develop a personalized meal plan that meets individual nutritional needs and preferences
• Read food labels to make informed choices and avoid potentially harmful ingredients

Impact of Maternal Nutrition on Fetal Development

• Maternal nutrition plays a critical role in fetal growth, development, and long-term health outcomes
• Inadequate nutrient intake can lead to fetal growth restriction, low birth weight, and increased risk of chronic diseases in adulthood
  • Folic acid deficiency increases the risk of neural tube defects (spina bifida, anencephaly)
  • Iron deficiency anemia is associated with preterm birth, low birth weight, and impaired cognitive development
• Excessive maternal weight gain and obesity are associated with an increased risk of macrosomia (high birth weight), childhood obesity, and metabolic disorders
• Gestational diabetes can lead to fetal hyperinsulinemia, macrosomia, and increased risk of type 2 diabetes in offspring
• Maternal malnutrition during critical periods of fetal development can result in epigenetic changes that affect gene expression and long-term health outcomes
  • The Dutch Hunger Winter study demonstrated the impact of maternal famine on offspring health, including increased risk of obesity, diabetes, and cardiovascular disease
• Adequate intake of omega-3 fatty acids, particularly DHA, supports fetal brain and eye development and may improve cognitive outcomes

Special Considerations and Risk Factors

• Adolescent pregnancy requires additional nutritional support to meet the needs of both the growing mother and developing fetus
  • Adolescent mothers are at higher risk for nutrient deficiencies, particularly iron, calcium, and folate
• Vegetarian and vegan diets during pregnancy require careful planning to ensure adequate intake of essential nutrients
  • Nutrients of concern include protein, iron, calcium, vitamin B12, and omega-3 fatty acids
  • Supplementation and fortified foods can help meet nutritional needs
• Multiple gestation (twins, triplets) increases nutritional demands and requires additional caloric and nutrient intake
  • Consultation with a registered dietitian can help ensure adequate nutrition for multiple fetuses
• Substance abuse during pregnancy, including alcohol, tobacco, and illicit drugs, can have detrimental effects on fetal development
  • Alcohol consumption is associated with fetal alcohol spectrum disorders (FASD) and neurodevelopmental impairments
  • Smoking during pregnancy increases the risk of preterm birth, low birth weight, and sudden infant death syndrome (SIDS)
• Chronic medical conditions, such as diabetes, hypertension, and autoimmune disorders, require specialized nutrition management during pregnancy
  • Pregestational diabetes requires strict blood glucose control to reduce the risk of congenital anomalies and fetal complications
  • Hypertension management may involve dietary modifications, such as reduced sodium intake and increased consumption of fruits and vegetables