chapter 11: maternal adaptation during pregnancy

trimesters

3 trimesters, 13 weeks each

1st trimester: 1st day of LMP to 13 weeks and 6 days

2nd trimester: 14 weeks and 0 days to 27 weeks and 6 days

3rd trimester: 28 weeks and 0 days to 40 weeks and 6 days

pregnancy signs categorized

presumptive signs: subjective, probably signs: objective, positive signs: the only signs that can determine a pregnancy with 100% accuracy

subjective signs (presumptive signs)

symptoms a woman experiences and reports (can be caused by other conditions), least reliable indicators of pregnancy

amenorrhea (4 weeks), nausea and vomiting(4-14 weeks), excessive fatigue(12 weeks), urinary frequency(6-12 weeks), breast tenderness(3-4 weeks), quickening(16-20 weeks), hyperpigmentation of skin(16 weeks), uterine enlargement(7-12 weeks), breast enlargement(6 weeks)

objective signs (probable signs)

symptoms observed or noted on physical exam by a health care provider

goodell sign: 5 weeks (cervical softening), chadwick sign: 6-8 weeks (bluish/purple discoloration of vagina/cervix), hegar sign: 6-12 weeks (softening of the uterine isthmus), McDonald sign: body of the uterus eases against the cervix

abdominal enlargement: 14 weeks, braxton hicks contractions: 16-28 weeks, uterine/placental souffle: 13-28 weeks (soft blowing sound heard with stethoscope, synchronous with mom’s pulse), ballottement: 16-28 weeks (passive fetal movement when examiner taps of cervix), positive pregnancy test: 4-12 weeks

diagnostic changes (positive changes)

positive proof of pregnancy

ultrasound, FHR, palpation of movement by the examiner, birth of baby

changes in the uterus during pregnancy

enlarges from 2-2.5 ounces to 2-2.5 lbs, capacity increases from 10 mL to 5,000 mL (effects of estrogen)

blood flow increases with 80-90% going to the placenta as the pregnancy progresses

braxton hicks: first trimester (may begin), second and third trimesters (more noticeable), thin out (efface) the cervix

uterus exits pelvic cavity around 12 weeks gestation

20 weeks gestation: fundal height reaches the umbilicus, fundal height measured in cms, typically corresponds to gestational weeks

hegar sign: 6-12 weeks (softening of the uterine isthmus)

changes in cervix during pregnancy

mucous plug (seals endocervical canal, prevents ascent of microorganisms)

Chadwick sign: vaso-congestion, Goodell sign: cervical softening, 6-8 weeks (result of vaso-congestion and estrogen)

changes in vagina during pregnancy

estrogenic effects = increased vaginal secretions (more acidic, white, and thick.. leukorrhea), loosening of connective tissue, increased vascularity

vaginal area is “glycogen-rich” promoting growth of Candida (diabetics, signs and symptoms of yeast infection), thrust

Chadwick sign

changes to ovaries during pregnancy

no ovulation (increased estrogen and progesterone, decrease FSH)

hCG (human chorionic gonadotropin) maintains the corpus luteum

progesterone: secreted by the corpus luteum until 6-7 weeks (placenta takes over)

changes to breast during pregnancy

increase in fullness, tenderness, and size (estrogen and progesterone)

tubercles of Montgomery (sebaceous glands) become prominent

striae, areola darkens, colostrum (may begin by end of 3rd trimester)

effects of pregnancy on GI system

nausea and vomiting (first trimester, 6-12 weeks)

treatments include: ginger, doxylamine succinate 10 mg (antihistamine), vitamin B-6

changes in taste and smell, ptylism and softened gums, gingivitis, pyrosis, constipation and bloating, hemorrhoids, gall bladder

effects of pregnancy on cardiovascular

pulse increases 10-15 bpm, cardiac output increses 30-50%, blood pressure (slight decrease, lowest mid-pregnancy, then returns to pre-pregnancy levels by 3rd trimester)

heart is laterally displaced to the left making it appear enlarged, 90% of pregnant women have a systolic mumur, vena caval syndrome/supine hypotensive syndrome

blood volume increased by 50%

physiologic anemia of pregnancy, iron need increases, concerns for women with pre-existing heart disease

effects of pregnancy on respiratory

progesterone causes decrease airway resistance

oxygen consumption increases 30-40% by term, breathing changes from abdominal to thoracic

respiratory rate and depth is increased

nasal congestion (rhinitis of pregnancy), edema of nasal mucosa (estrogen)

epistaxis: edema of nasal mucosa, voice changes in tone and quality

effects of pregnancy on urinary

increased blood flow to kidneys by 40-60%, kidneys enlarged, ureters dilate

increased kidney activity when lying on back, increased kidney activity in late pregnancy when lying on side

frequency, some increased risk of UTI, increased GFR, glycosuria

effects of pregnancy on musculoskeletal

increased acidic saliva, joint relaxation/waddling gait (relaxin and weight of gravid uterus)

increased lumbodorsal spinal curve/low back ache

diastasis recti

effects of pregnancy on integumentary

MSH: areola, nipple, perianal, umbilicus, axilla

linea nigra, chlosama/melasma, striae gravidarum, spider nevi

hair growth: decreased in pregnancy, shedding after pregnancy

nail growth: increased/brittle

sweat and sebaceous glands/acne, varicose veins, palmar erythema

effects of pregnancy on endocrine

thyroid enlarges

iodine: necessary for thyroid hormone formation, fetal brain development: dependent on adequate maternal thyroid levels, maternal BMR increases by 25%

pituitary

FSH and LH: inhibited in pregnancy due to hCG and prolactine

TSH: decreased in first trimester, thought to be related to NVP

prolactin: increased through inhibited by progesterone in pregnancy, placental delivery= decreased progesterone and increased prolactin

oxytocin: gradually increases, stimulates uterine contraction and milk let down

effects of pregnancy on adrenals and pancreas

adrenals:

cortisol - increased, keeps plasma glucose levels up (for fetal use), has anti-insulin, anti-inflammatory and anti-allergenic actions

aldosterone - increased, regulation of fluid and sodium

pancreas:

maternal glucose levels - low first ½ of pregnancy (diverted to fetus)

insulin resistance - 2nd ½ of pregnancy (effects of hPL from placenta)

prostaglandins: lipid substances not hormones, soften the cervix and help initiate labor, decreased levels may contribute to HTN and pre-eclampsia

placental secretion

hCG, hPL, estrogen, progesteron, and relaxin

hCG: stimulates estrogen and progesteone by corpus luteum (necessary for pregnancy)

hPL: insulin antagonist (ensures nutrient supply to fetus)

estrogen: promotes uterine and breast duct development

progesterone: maintains endometrium, inhibits contractions

relaxin: softens cervix, relaxes joints and ligaments, relaxes uterine muscle

effects of pregnancy on immune system

enhances inflammatory response, suppressed response to some foreign antigens (protects maternal system rejection of fetus), increased risk for certain maternal infections (UTI), some chronic conditions may worsen (diabetes), some chronic conditions may stabilize (asthma)

nutritional considerations during pregnancy

pre-pregnancy weight and diet, nutritional intake during pregnancy, daily prenatal vitamin (PNV) intake, dietary reference intakes (DRIs)

most nutrients needed in pregnancy can be obtained via a health diet

2 nutrients NOT obtained in diet alone: iron, folic acid, calcium

nutritional intake effects

inadequate intake: preterm birth, low birth weight (LBW), congenital anomalies

excessive intake: fetal macrosomia (difficult birth), neonatal hypoglycemia, possible childhood obesity

maternal weight gain in pregnancy

nutritional intake in pregnancy considered more important than total pregnancy weight gain

revisions on pregnancy weight recommendations consider the following: occurrence of multiple pregnancies, pregnancies in older women of older age, those who exceed ideal weight gain during pregnancy, number of women overweight/obese when becoming pregnant

recommendations: no dieting, no skipping meals, limit soda and caffeine intake, no diuretics, no sodium restriction (unless HCP advises), participate in reasonable daily physical activity

pattern of weight gain

1st trimester: 3.5-5 lbs

2nd and 3rd trimester: 1lb a week

total rang: 25-35 lbs

maternal age: teen moms have extra nutrient needs

maternal parity: close proximity of pregnancies increases risk, special attention to nutritional needs

special pre-pregnancy weight and nutritional considerations

underweight: 28-40 lbs (BMI less than 18.5)

overweight: 15-25 lbs (BMI = 25-29.9)

obese: 11-20 lbs (BMI is 30 or higher)

calories

first trimester: no change in caloric requirements

second and third trimester: extra 300 calories/day

carbohydrates (CHOs)

provide energy, spare protein for fetal growth, needs increase last 2 trimesters

protein

growth and maintenance of tissue and energy

total intake: 80 g/day (pregnancy and lactation)

fat

provides energy

DHA (omega 3 fatty acids) - fetal brain growth, decreased risk of gestational HTN, LBW and preterm birth

sources: oily fish (tuna), fortified dairy and soy products, walnuts, flaxseed and canola oil

calcium

energy, cell production, bone mineralization

supplements: decreases risk of pre-eclampsia

amount needed: 1,000 mg/day (pregnancy and lactation)

inadequate intake: demineralization of bone in mom to meet fetal needs

best sources: milk and dairy products (food is the preferred source for calcium)

iodine

fetal neuro development

deficiency: impaired brain development (most widespread cause), cretinism in baby (physical deformities, learning disabilities)

sources: fish and iodized salt as well are dairy, eggs, liver

sodium

not restricted in pregnancy

iron

for growth and brain development for the fetus and anemia prevention for mom

absorbed best with vitamin C and between meals, baby stores in liver use during first 3-4 months after birth

sources: meats, green leafy vegetables, legumes, dried fruit, whole grains, peanut butter, bean dip, whole wheat fortified breads and cereals

pregnancy: 27 mg/day supplement needed, cannot obtain enough in diet, lactations: 9mg/day

teach: take with meals (decrease GI upset), include plenty of fluid (constipation)

fat soluble vitamins

A, D, E, K

stored in liver

overdose: hair loss, GI upset, dry and cracked skin

vitamin A

importance: vision and eye formation

retinol: a form vitamin A, needed for healthy eyes in the baby

pregnancy: 770 mcg/day lactation: 1,300 mcg/day

vitamin D

absorption and utilization of calcium and phosphorous

deficiency: improper bone calcification (rickets)

those at risk: living in northern latitudes in the winter, routine use of high SPF sunscreen

sources: sunlight, milk, butter, eggs

pregnancy and lactation: 5mcg/day

vitamin E

antioxidant, protects health of cell membrane

overdose: abnormal blood coagulation in the newborn

sources: veggies, oils, fats, eggs, grains, greens

vitamin K

necessary for synthesis of prothrombin and normal blood clotting, synthesized by bacteria in the gut

babies have a sterile gut (receive vit K injection after birth)

sources: leafy greens, liver

antibiotics: inhibit synthesis

vitamin C

formation of connective tissue, collagen, and vascular system

deficiency: scurvy (muscle weakness and capillary hemorrhages)

babies at risk: fed only cow’s milk, mom takes mega doses of vit. c (rebound scurvy)

sources: citrus fruits, broccoli, tomatoes, strawberries

pregnancy: 85mg/day, lactation:120mg/day

B vitamins

cell respiration and energy metabolism

thiamine (B1), riboflavin (B2), B6 - helps with nausea in pregnancy (fish, pork, lentils, wheat germ), B-12 - animal proteins, vegans at risk, decreased amounts associated with infertility

folic acid (folate)

neural tube development

deficiencies: neural tube defects (spina bifida, anecephaly, etc.)

those at risk: multiples, those on dilantin (seizures)

sources: dark green vegetables (broccoli, romaine lettuce, spinach), baked beans, black-eyed peas, citrus fruits, peanuts, liver

pregnancy: 600 mcg/day, lactation: 500 mcg/day

fluid during pregnancy and lactation

at least 1 quart of water daily (32 oz, 8 glasses)

artificial sweeteners

use in pregnancy: controversial (some approve, some advise against), few studies

associated with: higher birth weight, childhood obesity

mercury in fish

all fish contains some mercury, fish oils: contain omega 3 fatty acids, important for fetal growth and brain development

types of fish low in mercury and high in omega 3: shrimp, catfish, pollock, haddock, canned light tuna, salmon, sole, cod, lobster, tilapia

fish to avoid due to higher mercury levels: shark, orange roughie, swordfish, king mackerel, ahi tuna, tilefish

listeriosis

contracted by exposure to listeria (bacteria) in soil, groundwater, animals and on plants

danger to fetus: can be passed via placenta, preterm birth, miscarriage, stillbirth, neonatal death

treatment: ampicillin

to avoid: refrigerate perishable foods quickly, wash hands when preparing foods, wash hands after handling deli, hot dogs, lunch meats, etc.

avoid: soft cheeses, refrigerated smoked seafood, store-made salads, unpasteurized milk or unpasteurized milk products

salmonella

contracted by consuming food or water contaminated by affected feces

to avoid: no raw meat, poultry, seafood, no raw or undercooked eggs, no unpasteurized dairy products, wash fruits and vegetables prior to consumption, wash hands after use of toilet, wash hands after handling pets

signs and symptoms: nausea, vomiting, diarrhea, stomach cramps, possible fever, chills and headache

lactose intolerance

lack lactase (enzyme)

signs and symptoms: abdominal cramping, bloating, loose stools

most common in: Asians, African Americans, Middle Eastern descent

recommendation: lactose-free dairy products

alternate calcium sources: fortified OJ, soy milk, peanuts, almonds, sunflower seeds, broccoli, kale, salmon, molasses

vegan and vegetarian diets

adequate in pregnancy and lactation, must be well planned and include variety of foods

vegetarian diets: lacto-ovo-vegetarian, lacto-vegetarian

vegan: omit all foods originating from animals, eat only plant-based foods

concerns: ensure adequate - protein, calcium, and iron intake, weight gain, vit. B-12 and vit. D

nutrient suggestions for vegans

protein: soy foods, beans, lentils, nuts, grains, seeds

iron: variety of meat alternatives with vitamin C rich foods

calcium: soy, calcium-fortified orange juice and tofu

vitamin B-12: fortified soy foods and B-12 supplement

pregnancy discomforts, psychosocial factors, eating disorders

common discomforts: nausea and vomiting, changes in smell and taste, can affect intake

psychosocial factors: personal feelings about the pregnancy, social environment and support system

eating disorders: anorexia, bulimia

pica

intense craving for eating non-food items over a period of at least 1 months

anemia - can result from pica

ex. soil, clay, ice, laundry starch, chalk, burnt matches, paint chips, egg shells, etc.

considerations: if anemic in pregnancy and patient has a good diet, assess for pica

treatment: iron supplementation

psychosocial adaptations during pregnancy

1st trimester: disbelief, ambivalence, focus on self

2nd trimester: introspection, excitement, body changes

3rd trimester: pride, anxiety, fatigue and physical discomforts, feels vulnerable to rejection, increased worry, may retreat into safety of her home, burst of energy

experienced throughout pregnancy: introversion, mood swings, body image changes

4 psychologic tasks

safe passage through pregnancy, labor, and birth

acceptance of child by others

acceptance of self in maternal role to infant

learn to give of self for child

siblings reaction

reaction: age-dependent (may regress or ignore)

include to the extent possible

reinforce love that the child is not being replaced

father throughout pregnancy

1st trimester: pride, ambivalence, feel left out, confused by moms mood changes, may seem unreal

2nd trimester: attachment, anxiety, wife’s appearance, good communication is key

3rd trimester: visualize parental role, special time, and any fears

couvade syndrome

unintentional development of physical symptoms by woman’s partner

fatigue, increased appetite, difficulty sleeping, others