Comprehensive Pregnancy Study Notes (Week 3 Core Content)

Maternal Adaptations

• Chadwick sign: bluish-purple coloration of the vaginal mucosa and cervix
• Goodell sign: softening of the cervix
• Hegar sign: softening of the lower uterine segment or isthmus

Signs of Pregnancy

Presumptive pregnancy signs

• Fatigue (12 weeks)
• Breast tenderness (3 to 4 weeks)
• Nausea and vomiting (4 to 14 weeks)
• Amenorrhea (4 weeks)
• Urinary frequency (6 to 12 weeks)
• Hyperpigmentation of skin (16 weeks)
• Fetal movements (quickening) (16 to 20 weeks)
• Uterine enlargement (7 to 12 weeks)
• Breast enlargement (6 weeks)

Probable pregnancy signs

• Braxton Hicks contractions (16 to 28 weeks)
• Positive pregnancy test (4 to 12 weeks); HCG level > $25 \, mU/mL$
• Abdominal enlargement (14 weeks)
• Ballottement (16 to 28 weeks)
• Goodell sign (5 weeks)
• Chadwick sign (6 to 8 weeks)
• Hegar sign (6 to 12 weeks)

Positive pregnancy signs

• Ultrasound verification of embryo or fetus (4 to 6 weeks)
• Fetal movement felt by experienced clinician (20 weeks)
• Auscultation of fetal heart tones via Doppler (10 to 12 weeks)

Uterus and Cervical Changes

• Uterus: Increase in size, weight, length, width, depth, volume, and overall capacity; pear shape to ovoid shape; positive Hegar sign
• Enhanced uterine contractility; Braxton Hicks contractions
• Ascent into abdomen after first 3 months
• Fundal height by 20 weeks’ gestation at level of umbilicus; 20 cm; reliable determination of gestational age until 36 weeks’ gestation
• Cervical changes: Softening (Goodell sign); mucus plug formation; increased vascularization (Chadwick sign); ripening about 4 weeks before birth

Vagina and Ovaries

• Vagina: Increased vascularity with thickening; lengthening of vaginal vault; secretions more acidic, white, and thick (leukorrhea)
• Ovaries: Enlargement until 12th to 14th week; cessation of ovulation

Breast and GI

Breast

• Increase in size and nodularity to prepare for lactation; tenderness, increase in nipple size, becoming more erect and pigmented (estrogen and progesterone)
• Production of colostrum: antibody-rich, yellow fluid that can be expressed after the 12th week; conversion to mature milk after delivery

GI

• Gums: hyperemic, swollen, and friable (due to estrogen and blood vessel proliferation)
• Ptyalism; dental problems; gingivitis
• Decreased peristalsis and smooth muscle relaxation; constipation; increased venous pressure; hemorrhoids
• Slowed gastric emptying; heartburn (decrease caffeine, chew slowly, stay sitting up after eating)
• Prolonged gallbladder emptying
• Nausea and vomiting (NPO if needed)

Cardiovascular and Respiratory

Cardio

• Increase in blood volume: ext{Volume}
  ightarrow 1.5 imes ext{prepregnancy}
• Increase in cardiac output; increased venous return; increased heart rate
• Slight decline in blood pressure until midpregnancy, then returning to prepregnancy levels
• Increase in number of RBCs; plasma volume > RBC leading to hemodilution (physiologic anemia)
• Increase in iron demands, fibrin and plasma fibrinogen levels, and some clotting factors, leading to hypercoagulable state

Respiratory

• Breathing more diaphragmatic than abdominal due to increased diaphragmatic excursion, chest circumference, and tidal volume (≈40%)
• Increase in oxygen consumption
• Congestion secondary to increased vascularity

Renal and Musculoskeletal

Renal

• Dilation of renal pelvis; elongation, widening, and increase in curve of ureters
• Increase in length and weight of kidneys
• Increase in glomerular filtration rate; increased urine flow and volume
• Increase in kidney activity with woman lying down; greater increase in later pregnancy with woman lying on side

Musculoskeletal

• Softening and stretching of ligaments holding sacroiliac joints and pubis symphysis
• Postural changes: increased swayback and upper spine extension
• Forward shifting of center of gravity
• Increase in lumbosacral curve (lordosis); compensatory curve in cervicodorsal area
• Waddle gait

Integumentary and Endocrine

Integumentary

• Hyperpigmentation; mask of pregnancy (facial melasma)
• Linea nigra
• Striae gravidarum
• Varicosities
• Vascular spiders
• Palmar erythema
• Decline in hair growth; increase in nail growth

Endocrine

• Thyroid gland: slight enlargement; increased activity; increase in BMR
• Pituitary gland: enlargement; decrease in TSH, GH; inhibition of FSH and LH; increase in prolactin, MSH; gradual increase in oxytocin with fetal maturation
• Pancreas: insulin resistance due to hPL and other hormones in second half of pregnancy
• Adrenal glands: increase in cortisol and aldosterone secretion
• Prostaglandin secretion
• Placental secretion: $hCG,\, hPL,\, relaxin,\, progesterone,\, estrogen$

Nutritional Needs

• Direct effect of nutritional intake on fetal well-being and birth outcome
• Need for vitamin and mineral supplement daily
• Folic acid increase – prevents neural tube defects (+ alpha fetoprotein)
• Example: Citrus fruits
• Dietary recommendations: increase protein, iron, folate, and calories
• Use of USDA’s Food Guide MyPlate: increase fruits, veggies, and whole grain; decrease saturated fats, trans fats, and cholesterol
• Avoidance of some fish due to mercury content
• Avoid smoking and alcohol

Maternal Weight Gain

• Healthy weight BMI: 25 to 35 lb
  • First trimester: 3.5 to 5 lb
  • Second and third trimesters: 1 lb/week
• BMI < 19.8: 28 to 40 lb
  • First trimester: 5 lb
  • Second and third trimesters: +1 lb/week
• BMI > 25: 15 to 25 lb
  • First trimester: 2 lb
  • Second and third trimesters: 2/3 lb/week

Terminology

• G (gravida): the current pregnancy
• T (term births): the number of pregnancies ending >37 weeks’ gestation, at term
• P (preterm births): the number of preterm pregnancies ending >20 weeks or viability but before completion of 37 weeks
• A (abortions): the number of pregnancies ending before 20 weeks or viability
• L (living children): number of children currently living

Nagele’s Rule and Dating

• Nagele’s rule: used to calculate estimated date of birth (EDB/EDD)
• Steps: Use first day of LNMP; Subtract 3 months; Add 7 days; Add 1 year
• Example: LNMP = 11/21/2007
  • Subtract 3 months: 8/21/2007
  • Add 7 days: 8/28/2007
  • Add 1 year: 8/28/2008 → EDB
• Expression:
  $ext{EDB} = ext{LMP} - 3 ext{ months} + 7 ext{ days} + 1 ext{ year}$
• Note: Ultrasound dating is the best method for dating a pregnancy

Pelvimetry

• Pelvic capacity determines whether fetus can pass through birth canal
• Used to help decide on elective cesarean if cephalopelvic disproportion risk
• Timing: 37–39 weeks gestation
• Adequate pelvis inlet: >$12\text{ cm}$

Lab Tests and Follow-Up

• Urinalysis; Complete blood count; Blood typing; Rh factor
• Rubella titer; Hepatitis B surface antigen; HIV, VDRL, RPR testing
• Cervical smears; Ultrasound
• Follow-up visits:
  • Every 4 weeks up to 28 weeks
  • Every 2 weeks from 29 to 36 weeks
  • Every week from 37 weeks to birth
• Assessments at visits:
  • Weight and BP compared to baseline values
  • Urine testing for protein, glucose, ketones, nitrites
  • Fundal height; Quickening/fetal movement; Fetal heart rate

Fundal Height

• Used to assess fetal growth; distance from pubic bone to top of uterus in cm
• After 24 weeks, fundal height often matches the weeks of gestation (± 2 cm)

Assessment of Fetal Well-Being

• Amniocentesis (physical abnormalities)
• Ultrasonography
• Doppler flow studies (blood flow)
• Alpha-fetoprotein analysis (neural tube defects)
• Nonstress test (NST); measures fetal heart rate in response to movement
• Contraction stress test; evaluates fetal response to contractions
• Biophysical profile

Kick Counts

• Purpose: monitor fetal movements to detect distress
• Typical goal: 10 movements (kicks, flutters, or rolls) in 1 hour in third trimester (weeks 28–40)
• Steps to count:
  • Choose a quiet time when fetus is typically active
  • Lie on left side or sit semi-Fowler
  • Place hands on belly and start a timer
  • Count each kick until 10; note minutes needed
  • Daily monitoring after 28 weeks (26 weeks if high risk)

Trimester Symptom Snapshot

• 1st trimester symptoms: urinary frequency, fatigue, nausea/vomiting, breast tenderness, constipation, nasal stuffiness/epistaxis, cravings, leukorrhea, backache, hemorrhoids, flatulence with bloating
• 2nd trimester symptoms: return of first-trimester discomforts, shortness of breath and dyspnea, heartburn/indigestion, dependent edema, Braxton Hicks contractions
• 3rd trimester symptoms: as above with emphasis on increased discomfort and pressure

Self-Care for Pregnancy

• Personal hygiene; avoidance of saunas and hot tubs; perineal care
• Dental care; breast care; proper clothing; appropriate exercise; sleep/rest
• Sexual activity and sexuality considerations; employment; travel (Zika) precautions
• Immunizations and medications during pregnancy

Feeding Choices

Breast-feeding

• Advantages and disadvantages
• Colostrum: first milk; lasts 2–4 days after birth
• Transitional milk: begins ~4 days after birth; lasts ~2 weeks; nutrient- and antibody-rich
• Mature milk: from ~14 days after birth onward; provides necessary nutrients
• Oxytocin release during breastfeeding

Bottle feeding

• Advantages and disadvantages

Fetal Heart Rate and Variability (Overview)

• Tachycardia: >$160\text{ bpm}$
• Baseline heart rate: $110-160\text{ bpm}$
• FHR Variability:
  • Absent variability: amplitude range undetectable
  • Minimal: < $5\,\text{ BPM}$
  • Moderate: $6-25\,\text{ BPM}$
  • Marked: > $25\,\text{ BPM}$

Fetal Heart Rate Patterns (illustrative labeling)

• Accelerations, Early Decelerations, Variable Decelerations, Late Decelerations are patterns observed on FHR tracing
• Context: Uterine contractions may accompany decelerations
• Notation: A, B, C, D, E correspond to different waveform events on the tracing

Nonstress Test (NST)

• Definition: Test measuring fetal heart rate in response to movement; reactive vs nonreactive
• Purpose: Ensure fetus is healthy and getting enough oxygen; typically after 28 weeks
• Process: Two elastic belts with sensors; records for about 30 minutes; charted results

When to Use NST

• Post-dates (past due date)
• High-risk pregnancy
• Decreased fetal movement
• Fetus small for gestational age
• Expecting multiples
• Rh-negative

NST Results: Reactive vs Nonreactive

• Reactive NST (reassuring): fetus’ heart rate accelerates with movement or contractions
• Criteria: at least two accelerations within 20 minutes
• Thresholds by gestational age:
  • ≥ 32 weeks: at least two accelerations of at least $15\times 15\text{ BPM and seconds}$ within 20 minutes
  • < 32 weeks: at least two accelerations of at least $10\times 10\text{ BPM and seconds}$ within 20 minutes
• Nonreactive NST
  • Accelerations do not occur or are insufficient within the testing period
  • May indicate need for additional testing; could reflect sleep state, oxygen issues, or medication effects

Additional Notes on NST and FHR Interpretation

• Reactive NST implies adequate fetal oxygenation and autonomic response; nonreactive NST requires follow-up testing to determine cause
• Contractions and fetal movements are key triggers for accelerations
• Clinical context and repeat testing guide management decisions