Maternal Adaptation during Pregnancy Chapter 6: Maternal Adaptation during Pregnancy

Signs of Pregnancy Presumptive (possible) signs: Subjective data woman experiences and reports to health care provider Taken alone, each sign can have other causes besides pregnancy Probable signs: Objective signs measured by trained examiner Positive signs: Diagnostic confirmation Ultrasound, fetal heartbeat, etc.

Signs of Pregnancy (cont.) Possible signs of pregnancy and other potential causes Tender breasts Could be caused by hormonal changes Amenorrhea (missed period) Hormonal imbalance, emotional distress, or illness Frequent urination UTI, nervousness, etc.

Signs of Pregnancy (cont.) Probable signs of pregnancy and other potential causes Presence of hCG in blood May be due to hydatidiform mole Presence of hCG in urine May be due to choriocarcinoma Uterine growth May be due to tumors Ballottement of fetus May be elicited by a tumor

Signs of Pregnancy (cont.) Probable signs of pregnancy (objective) Chadwick sign The bluish-purplish color of the cervix, vagina, and perineum Hegar sign Softening of the uterine isthmus Goodell sign Softening of the cervix

Signs of Pregnancy (cont.) Positive signs of pregnancy Visualization of fetus by ultrasound Fetal heart sounds by fetal stethoscope Fetal movements palpable by a trained practitioner Fetal movements visible

Question Starting somewhere around the sixth week of the pregnancy hCG begins to be found in the urine. However, hCG in urine is not a positive sign of pregnancy. What could its appearance in the urine be due to? a. Choriocarcinoma b. Hydatidiform mole c. UTI d. Pelvic tumor

Answer a. Choriocarcinoma Rationale: Pregnancy tests measure the presence of human chorionic gonadotropin (hCG) in the urine or the blood. hCG levels can be elevated in conditions other than pregnancy, such as hydatidiform mole and choriocarcinoma.

Physiologic Adaptation to Pregnancy Reproductive changes Uterine changes Change in weight, capacity Changes in wall structure Expansion from pelvis into abdominal cavity Blood supply increases

Physiologic Adaptation to Pregnancy (cont.) Reproductive changes (cont.) Cervix and ovaries Vascularity increases, and glandular tissue multiplies during pregnancy Thick mucous plug develops in the opening of the cervix Ovulation stops Corpus luteum continues to function and produces progesterone for approximately 6 to 7 weeks

Physiologic Adaptation to Pregnancy (cont.) Reproductive changes (cont.) Vagina and perineum Vagina and perineum are affected by hormonal changes and increased blood supply to the area Vagina takes on a bluish-purplish hue, Chadwick sign Increased secretions

Physiologic Adaptation to Pregnancy (cont.) Reproductive changes (cont.) Breasts Tenderness in the first few weeks of pregnancy Nodularity of breast tissue Prominent areola with deepened pigmentation Prominent projections of Montgomery tubercles

Physiologic Adaptation to Pregnancy (cont.) Endocrine changes Pituitary enlarges Prolactin levels increase progressively Increased protein binding Thyroid gland increases in size Need for insulin increases

Physiologic Adaptation to Pregnancy (cont.) Hematologic changes Blood volume increases by 40% to 45% Red blood cell volume increases up to 30% Plasma volume increases by 50% Hemoglobin slightly decreases to 11 to 12.5 g/100 mL Hematocrit decreases

Physiologic Adaptation to Pregnancy (cont.) Cardiovascular changes Blood pressure decreases slightly Heart rate increase averages 10 to 15 beats per minute Cardiac output increases Supine hypotensive syndrome Latter half of pregnancy

Physiologic Adaptation to Pregnancy (cont.) Respiratory changes Nasal mucosa edematous due to vasocongestion Nasal congestion and voice changes possible Accommodations to maintain lung capacity May feel short of breath when eupneic Third trimester diaphragm pressure

Physiologic Adaptation to Pregnancy (cont.) Musculoskeletal changes Lordosis increases Diastasis recti abdominis GI changes Intestines are displaced to the sides and upward Pressure changes in stomach and esophagus Leads to heartburn Constipation

Physiologic Adaptation to Pregnancy (cont.) Urinary changes Renal and ureteral dilation Glomerular filtration rate increases by 50% Glycosuria

Physiologic Adaptation to Pregnancy (cont.) Integumentary changes Chloasma (mask of pregnancy) Brown blotchy areas on the forehead, cheeks, and nose Linea nigra The skin in the middle of the abdomen may develop a darkened line Striae (stretch marks) May develop on the abdomen in response to elevated glucocorticoid levels

Psychological Adaptation to Pregnancy First-trimester task Accept the pregnancy Second-trimester task Accept the baby Third-trimester task Prepare for parenthood

Changing Nutritional Requirements of Pregnancy Fetus needs nutrients and energy to build new tissue Woman needs nutrients to build her blood volume and maternal stores Increased demand for energy and for almost every nutrient type Most nutrient requirements can be met through careful attention to diet Several nutrients require supplementation during pregnancy

Changing Nutritional Requirements of Pregnancy (cont.) Energy requirements and weight gain Increased caloric intake of 300 kcal/day During second, third trimesters Recommended weight gain dependent upon prepregnancy BMI First trimester: 3 to 4 lb total Remainder of pregnancy: 1 lb per week Total weight gain: 25 to 35 lb for a woman with a normal BMI

Nutrients Needed during Pregnancy and their Functions Protein requirements Growth and repair of fetal tissue, placenta, uterus, breasts, and maternal blood volume Mineral requirements Prevent deficiencies in the growing fetus and maternal stores Iron Formation of hemoglobin; essential to the oxygen- carrying capacity of the blood

Nutrients Needed during Pregnancy and their Functions (cont.) Mineral requirements (cont.) Calcium Nerve cell transmission, muscle contraction, bone building, and blood clotting Phosphorous: Promotes strong bone growth Zinc Fetal growth and maternal milk production Iodine Promotes normal thyroid activity, preventing specific birth defects

Vitamin Requirements during Pregnancy Folic acid (Vitamin B9) Necessary for formation of the nervous system Prevents up to 70% neural tube defects Diet should include at least 400 mcg of folic acid per day Vitamin A Recommended intake via beta-carotene Too much can be toxic to the fetus Too little can stunt fetal growth and cause impaired dark adaptation and night blindness

Vitamin Requirements during Pregnancy (cont.) Vitamin C Essential in the formation of collagen, a necessary ingredient to wound healing Vitamin B6 Necessary for the healthy development of the fetus’s nervous system Vitamin B12 Needed to maintain healthy nerve cells, RBCs, form DNA

Question Which vitamin is most important for development of the central nervous system? a. Vitamin B12 b. Vitamin B6 c. Vitamin B9 d. Vitamin B1

Answer c. Vitamin B9 Rationale: Folic acid (B9) is a B vitamin that can prevent up to 70% of birth defects of the central nervous system called neural tube defects.

Dietary Supplementation Iron supplementation is recommended for all pregnant women after 28 weeks' gestation. If the woman has low hemoglobin, is obese, or is carrying twins, higher doses of iron are necessary. Folic acid supplementation is recommended prenatally and during pregnancy to prevent neural tube defects.

Food Safety During Pregnancy Food preparation guidelines Listeria precautions Seafood recommendations

Special Nutritional Considerations Vegetarianism Pica