Reproductive Exam 1: Physiology & Adaptations of Pregnancy; Physiology of Labor and Birth

Reproductive changes during pregnancy: uterine and ovary

• Uterine: Predictable growth pattern, Braxton Hicks contractions

• Ovaries: Corpus luteum sustains early pregnancy, releases estrogen and progesterone

Reproductive changes during pregnancy: vaginal/cervical and breasts

• Vaginal & Cervical changes

  • Goodell sign – soften of cervix

  • Chadwick sign – bluish color of cervix

• Breasts: 

  • Larger, areola darken

  • estrogen makes mammary tissues highly vascular, Striae gravidarum appear

  • Progesterone stimulates growth and alveoli

  • Colostrum appears (nutrient-dense fluid)

Endocrine changes during pregnancy

• HPA: prolactin, ACTH, and GH levels increase 

• Pituitary gland gradually produces more prolactin as pregnancy goes on

• Pancreas produces increased levels of insulin as pregnancy progresses, countered by placenta secreting anti-insulin hormone (hPL) to keep glucose levels stable

• Placental Hormones: hCG, hPL, progesterone, estrogen

cardiovascular changes during pregnancy

• Expanded blood volume (30-50%) increases cardiac output (but not BP)

  • Can result in anemia

• Systolic murmur usually heard due to increased cardiovascular load

• HR increases 10-20 BPM

• Mild leukocytosis is normal

• Pregnancy causes decreased SVR, B/P may drop 10-15 mmHg

• Supine hypotensive syndrome

renal changes during pregnancy

• Renal blood flow increases 50% (increased urinary frequency and drop in SCr) 

• Delayed clearance and incomplete emptying increases risk of urinary tract infection

• GFR leads to glucosuria, proteinuria, and albuminuria

Integumentary changes during pregnancy

• Increased sweat gland activity

• Hyperpigmentation (linea nigra, striae gravidarum, melasma) 

• Vascular changes (angiomas, varicose veins, palmar erythema, pruritus) 

• Increased hair and nail growth

GI changes during pregnancy

• Mouth: gingivitis, gums bleed easily, ptyalism (increased salivation)

• N/V, heartburn/reflux

  • Hyperemesis Gravidarum (HEG): When nausea and vomiting of pregnancy interferes with ADLs, causes weight loss, food intolerance

• Increased intestinal emptying time and decreased mobility → constipation

• Gallstones and cholestasis

immune system changes throughout pregnancy

• Conception – 12 weeks: Weakened immune system

• 12-34 weeks: hyperimmune

• 34 weeks-birth: decreased immune response

• Maternal IgG antibodies cross placenta to passively protect the fetus (short term immunity)

Naegle’s Rule for due date

First Day of Last Menstrual Period (LMP) minus 3 months + 7 days

Fundal height use and process

• Provider uses a tape measure to measure from pubic bone to the top of uterus

• This measurement (in cm) reflects the size of your uterus

• indicator of fetal growth and gestational age

GTPAL

• Gravidity: Total number of pregnancies 

• Parity: Number of pregnancies greater than or equal 20 weeks, irrespective of outcome (Primipara– pregnant for the first time or multipara– 2+ pregnancies)

  • Term: Born at or after 37 weeks

  • Preterm: Born 20-36.6 weeks

  • Abortions: Spontaneous or elective 

  • Living: Number of living children

Potential Signs of Impending Labor

• descent or “lightening” of fetus

• cervical changes, “ripening”

• blood show/losing of mucus plus

• nesting

• GI distress (N/V/D)

• increasing frequency of Braxton-Hicks contractions

signs of True Labor

• Rupture of membranes

• Descent of the presenting part of the fetus

• Generally, contractions become stronger, more regular, and longer despite comfort measures

false labor

• Braxton-Hicks contractions: no pattern, may go away with rest OR activity

• Can occur/begin days or weeks before true labor

• Can be painful to the patient and cause distress

• No cervical change

Presumptive Signs (Subjective Signs)

• Amenorrhea (absence of menstruation)

• N/V

• Breast tenderness and enlargement

• Fatigue

• Frequent urination

• Quickening (first fetal movements felt by mother, usually around 18–20 weeks for first-time moms)

• Skin changes (e.g., chloasma, linea nigra, striae gravidarum)

Probable Signs (Objective Signs)

• Positive pregnancy test (detects hCG but false positives/negatives possible)

• Chadwick’s sign: bluish discoloration of cervix/vagina

• Goodell’s sign: softening of the cervix

• Hegar’s sign: softening of the lower uterine segment

• Ballottement: passive fetal movement felt when the cervix is tapped

• Braxton Hicks contractions

Positive Signs (Diagnostic Signs)

• Fetal heartbeat detected by Doppler (around 10–12 weeks) or fetoscope (17–20 weeks)

• Fetal movement felt by examiner (not just mother)

• Visualization of the fetus on ultrasound (can be detected as early as 5–6 weeks with transvaginal ultrasound)

4 stages of labor

1. Dilation Stage

2. Expulsion (Pushing) Stage

3. Placental Stage

4. Recovery Stage

First stage/dilation stage events

• cervical effacement and dilation

• 3 phases

  • latent/early labor

  • active labor

  • transition

second stage/expulsion stage events

• fetal expulsion

• 10cm/complete dilation

third stage/placental stage events

• placental separation and expulsion

• delivery of placenta

fourth stage/recovery stage events

• 1-2 hours postpartum

• period of high maternal and fetal risks

Describe data collected during the initial assessment of the laboring patient

• dilation: widening/opening

• effacement: thinning of cervix muscle fibers

• station: where the lowermost part of the fetal presenting part resides in relation to the ischial spines (plus or minus)

Understand the 4 P’s that affect the labor and birth process

• Powers– contractions (strength, frequency, adequacy)

• Passage– bony pelvis (shape, trauma, age)

• Passenger– fetus/baby (size, presentation, positioning, conditions)

• Person/Psyche– coping, support, comfort, pain, fatigue

fetal factors that can influence labor/birth

• size/head size

• presentation– part of the fetus that enters the pelvis first

• fetal lie– relation of the long axis of the fetus to the long axis of the mother

• fetal attitude– relation of fetal body parts to one another

fetal presentation positions

• Cephalic (head first)

• Breech

  • Frank: feet near head, butt presents first

  • Complete: feet near butt, both present first

  • Footling: One or both feet present below the buttocks, foot/feet present first

• Shoulder 

fetal lie positions

• Vertex or longitudinal: up and down

• Transverse: side to side

fetal attitude positions

• Vertex presentation: head completely flexed (ideal)

• Military presentation: moderate flexion

• Brow presentation: poor flexion (extension, “looking up”)

• Face presentation: full extension (looking out of pelvis)

List acceptable fetal heart rate and variability criteria in fetal monitoring

• Normal FHR is 100-160

• Variability: fluctuations in the FHR baseline that are irregular in amplitude and frequency

  • Absent– bad

  • Minimal: <5

  • Moderate: 6-25, normal

  • Marked: over 25

  • Fetal sleep and medications can affect variability

  • Loss of variability can be a sign of fetal hypoxemia, metabolic acidosis, or fetal neurologic injury 

• Periodic changes

  • Accelerations always reassuring

  • Decelerations not always bad

Apply terminology used to describe contractions including frequency, duration, intensity for monitoring

• Frequency: beginning to beginning of 2 contractions

• Duration: how long a contraction lasts

• Intensity: palpation or internal monitor (subtracting the baseline uterine pressure from the peak height of the contraction)

Review characteristics/considerations in the assessment of rupture of membranes

• Marks beginning of labor

• Need to know time, characteristics (color, amount, odor)

• Test to confirm: Nitrazine paper/Amniswab, Fern test, Lab confirmation (Amnisure)

• Increased risk of infection

  • Check temp at least every 2 hours and for signs/symptoms of infection

  • Keep clean and dry