Biologic Foundations of Pregnancy

    1. Alterations affecting nutrition
      1. Physiological changes:
        1. Gastrointestinal system
          1. Gingivae soften and enlarge due to increased vascularity.
          2. Increased saliva production.
        2. Endocrine system
          1. Increased size and activity of pituitary, parathyroids, adrenals.
          2. Increased vascularity and hyperplasia of thyroid.
          3. Pancreas-increased insulin production during second half of pregnancy, needed to meet rising maternal needs; human placental lactogen (HPL) and insulinase deactivate maternal insulin; may precipitate gestational diabetes in susceptible women.
        3. Metabolism
          1. Basal metabolic rate (BMR)-increases 25% as pregnancy progresses, due to increasing oxygen consumption; protein-bound iodine (PBI) increases to 7-10 μg/dl; metabolism returns to normal by sixth postpartal week.
          2. Protein-need increased for fetal and uterine growth, maternal blood formation.
          3. Water retention-increased.
          4. Carbohydrates-need increases to spare protein stores.
            1. First half of pregnancy - glucose rapidly and continuously siphoned across placenta to meet fetal growth needs; may lead to hypoglycemia and faintness.
            2. Second half of pregnancy - placental production of antiinsulin hormones; normal maternal hyperglycemia; affects coexisting diabetes.
          5. Fat - increased plasma-lipid levels.
          6. Iron-supplements recommended to meet increased need for red blood cells (RBCs) by maternal/placental/ fetal unit.
      2. Assessment:
        1. Weight gain: 20-35 lb (11.5-16 kg); depends on Body Mass Index and prepregnant nutritional status.
        2. Normal pattern: first trimester, 2-5 lb (1-2.3 kg); remainder of gestation, approximately 1 lb/wk (0.4-0.5 kg/wk).
      3. Nursing care plan/implementation:
        4. Goal: health teaching
        1. Evaluate diet for adequacy of nutrient and caloric intake.
        2. Evaluate cultural, religious, and economic influences on diet.
        3. Review dietary recommendation for pregnancy with woman.
        4. Avoid dieting in pregnancy (even if obese).
        5. Supplement diet with vitamins, iron, or folic acid on advice of health provider.
        6. Ptyalism:
          1. Suck hard candies.
          2. Perform frequent oral hygiene.
          3. Maintain adequate oral intake (6-8 glasses/day).
          4. Use lip balm to prevent chapping.
        7. Epulis:
          1. Frequent oral hygiene.
          2. Use soft toothbrush.
          3. Floss gently.
          4. See dentist regularly.