1. Maternal Adaptation during Pregnancy
Chapter 6:
Maternal Adaptation during Pregnancy

2. 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.

3. 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.

4. 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

5. 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

6. 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

7. 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

8. 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.

9. 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

11. 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

12. 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

13. 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

14. 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

15. 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

16. 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

18. 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

19. 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

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

21. 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

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

23. 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

24. 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

25. 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

26. 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

27. 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

28. 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

29. 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

30. 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.

31. 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.

32. Food Safety During Pregnancy
Food preparation guidelines
Listeria precautions
Seafood recommendations

33. Special Nutritional Considerations
Vegetarianism
Pica