Comprehensive Study Notes: Pregnancy, Labor, and Fetal Monitoring (Transcript)

Portfolio and Study Logistics

  • Start a personal study portfolio for the semester. Use a binder (2-inch recommended) to store, organize, and track course materials.

  • Keep medication sheets (drugs discussed in lecture) and related assignments in the portfolio.

  • Three assignments to be completed for this unit:

    • Concept map on progestin (for contraception)

    • Assignment on oxytocin

    • Assignment on methergin (methylergonovine; note the lecturer spelled it as methergen in class)

  • The portfolio will be posted in the Health Care course materials (Medication portfolio form).

  • The plan is to pull the portfolio at the final evaluation to verify contents; it may or may not count toward a grade next semester (depends on program decision).

  • The portfolio is meant to help you study concepts consistently and keep track of progress across lectures.

  • Expect to hang and review the material: the portfolio is designed to be a rotating study resource you can refer back to during exams.

  • Practical piece: the “medicine portfolio form” outlines what needs to be documented (pregnancy-related changes, medications, and related notes).

  • The lecturer emphasizes keeping up with it and printing the required sheets for two-inch binders.

Anatomy and Physiological Changes in Pregnancy

  • Uterine growth and fundus (top of the uterus): The uterus expands as pregnancy progresses; the fundus rises higher in the abdomen.

  • Fundus height and gestational age:

    • By 16–18 weeks, measurements from the fundus can be used to estimate gestational age; the fundus is the top of the uterus and becomes palpable higher as pregnancy progresses.

    • After ~16 weeks, measurement is often taken from the symphysis pubis to the fundus to approximate gestational age.

  • Uterine blood flow at term: ~1200racmlmin1200 rac{ml}{min} to the uterus to support fetal needs and placental circulation.

  • The uterus is a muscle that contracts; contractions start at the top and progress downward as pregnancy advances.

  • Cervix changes during pregnancy:

    • Goodell’s sign: cervix becomes soft and pliable as pregnancy progresses.

    • Chadwick’s sign: bluish-purple color of vagina and cervix due to vascular engorgement; an early pregnancy sign.

  • Ovaries and hormones:

    • Ovaries secrete hormones (notably progesterone) to maintain a pregnancy and suppress menses.

  • Breasts:

    • Breast enlargement and tenderness due to hormonal changes as lactation prepares.

  • Cardiovascular changes:

    • Blood pressure tends to decrease due to systemic vasodilation; normal BP usually remains stable unless complications arise.

    • Cardiac size may increase to accommodate higher blood volume.

    • A mild heart murmur (S3) can be common during pregnancy and may resolve postpartum.

    • Blood volume increases by ~+45 ext{ ext{%}} over pre-pregnancy levels.

  • Respiratory changes:

    • Oxygen consumption increases by ~+20 ext{ ext{%}} to support fetal metabolism.

    • Tidal volume increases; respiratory rate may stay the same.

  • Gastrointestinal changes:

    • Progesterone relaxes smooth muscle including the esophageal sphincter, contributing to heartburn.

  • Urinary changes:

    • Bladder relaxes due to progesterone; increased uterine pressure from the growing fetus can cause stress incontinence.

  • Skin changes:

    • Hyperpigmentation is common; mask of pregnancy (melasma) and other pigment changes can occur; some report a “glow.”

  • Musculoskeletal changes:

    • Ligaments relax due to progesterone, facilitating pelvic expansion for delivery; may cause changes in shoe size and weight distribution.

  • Endocrine changes:

    • Pituitary gland increases prolactin (milk production) and oxytocin (contractions) production during pregnancy.

    • The pituitary also suppresses hormones that regulate the menstrual cycle during pregnancy.

  • Pancreas and glucose metabolism:

    • Early pregnancy: glucose may be 10–20% lower in the first trimester (risk of hypoglycemia in some patients).

    • Later pregnancy: risk of gestational diabetes increases; GTT is commonly performed around ~15extweeks15 ext{ weeks} in pregnancy.

    • Description of GTT: typically a glucose load (sugar water) with a timed blood draw (often 1 hour); abnormalities may require a follow-up test.

  • Vision and hearing:

    • Corneal edema can cause blurred vision during pregnancy; avoid new glasses until postpartum if possible.

    • Temporary ear fullness or congestion can occur.

  • Immune system:

    • Immune function is modulated: decreased risk of fetal rejection, yet autoimmune diseases (e.g., rheumatoid arthritis) sometimes improve during pregnancy; exact mechanism is not fully understood.

Diagnostic Classifications and Initial Assessment of Pregnancy

  • Classifications of pregnancy (per the textbook chart referenced):

    • Presumed (or presumptive): symptoms reported by the patient such as amenorrhea, nausea, vomiting, fatigue, breast changes, vaginal/cervical color changes, fetal movement (felt by patient) and other signs.

    • Probable: signs that are more objective but not definitive (e.g., ballotment, fetal outline palpation, and some cervicovaginal changes described in clinical texts).

    • Positive: diagnostic confirmations such as ultrasound visualization of the fetus, fetal heart tones, and fetal movement felt by examiner.

  • Classic presumptive signs cited in the lecture include amenorrhea, nausea/vomiting, fatigue, breast changes, vaginal/cervical color changes, and fetal movement reported by the patient.

  • Ballottement (probable sign): palpation or tapping of a floating fetus that rebounds with a definite movement; not definitive due to possible fibroids or other masses.

  • Palpation of fetal outline (probable sign): examiner palpates fetal outline; not always definitive due to body habitus and other factors.

  • Positive confirmation signs include:

    • Visualization of fetal cardiac activity by ultrasound

    • Fetal heart tones detectable by Doppler or auscultation

    • Movement felt by the examiner during an exam

  • Important terminology for pregnancy history:

    • Gravida: number of times the person has been pregnant (including current pregnancy if applicable).

    • Para: number of pregnancies carried to a viable gestational age (often counted as term deliveries, preterm deliveries, abortions, and living children).

    • Primigravida: first pregnancy.

    • Multigravida: more than one pregnancy.

  • GTPAL terminology and example:

    • Gravida (G): total number of pregnancies, including current.

    • Term (T): pregnancies carried to term (37–42 weeks).

    • Preterm (P): pregnancies delivered between 20 and 37 weeks.

    • Abortions (A): pregnancies ending before 20 weeks (spontaneous or elective).

    • Living (L): number of living children.

  • Example problem from the lecture to practice GTPAL (paraphrased):

    • A woman is six months pregnant with a history of one spontaneous abortion and one elective abortion in the first trimester. She has a son born at 40 weeks and a daughter born at 34 weeks.

    • Answer breakdown:

    • Gravida: 5 (she has been pregnant five times)

    • Term: 1 (the son at 40 weeks)

    • Preterm: 1 (daughter at 34 weeks)

    • Abortions: 2 (one spontaneous, one elective in the first trimester)

    • Living: 2 (two living children)

    • Note: If twins are involved in any pregnancy, they count as one pregnancy for GTPAL, but the living count may differ depending on outcomes.

  • Naegele’s rule for estimated due date (EDDs):

    • EDD ≈ LNMP − 3 months + 7 days (with some rounding for month lengths and leap years).

    • The lecturer warns about occasional confusion with month counting and knuckle-ruler tricks; test expectations may vary, but Naegele’s rule is the standard approach.

  • Last Normal Menstrual Period (LNMP): the start date of the last normal menstrual period used to estimate gestational age.

  • Alternative mnemonic discussed in lecture: “Naegele’s method” and using knuckle counting as a teaching aid for month lengths; not a formal clinical method, but a learning tool in the session.

  • Weight gain and nutrition:

    • Typical recommended total weight gain during pregnancy is roughly 2535extpounds25-35 ext{ pounds} (varies by pre-pregnancy BMI).

    • Important nutritional emphasis: folic acid supplementation.

  • Folic acid supplementation:

    • Recommended dose: 0.4extmg/dayo0.8extmg/day0.4 ext{ mg/day} o 0.8 ext{ mg/day} for the first 3 months; after that, 0.6extmg/day0.6 ext{ mg/day}.

    • Rationale: prevents neural tube defects and supports fetal neural development; associated with reduced risk for cleft palate and other neural tube issues.

    • If patient is taking methotrexate or other interfering drugs, folic acid considerations may differ.

  • Diagnostic testing (overview): ultrasound, Doppler, CVS, amniocentesis, and non-stress testing

    • Ultrasound: used for early confirmation and dating; transvaginal ultrasounds are common in early pregnancy (around 8 weeks); can involve an external wand or transvaginal probe

    • Doppler ultrasound: used to assess blood flow in the umbilical cord and placenta

    • Chorionic villus sampling (CVS): typically performed around ~12 weeks to examine fetal chromosomes/DNA for suspected anomalies; relatively high reliability with some risk

    • Amniocentesis: performed later (often 15–20 weeks or later) to assess fetal lung maturity or chromosomal conditions, or in cases of suspected anomalies; involves sampling amniotic fluid via needle

    • Amniotic fluid assessment: ultrasound can detect oligohydramnios or polyhydramnios; amniosynthesis used to analyze fluid

    • Non-stress test (NST): evaluated to assess fetal well-being by monitoring fetal heart rate in response to fetal movement

  • Non-stress test (NST) specifics:

    • Reactive NST: at least two fetal heart rate accelerations within 20 minutes

    • Nonreactive NST: not meeting the reactive criteria; may require retesting, stimulus, or further testing

    • Interventions during NST include providing maternal glucose intake (orange juice or snack) to wake the fetus if sleeping, or adjusting maternal position to optimize placental perfusion.

Labor, Contractions, and Cervical Changes

  • Four Ps of labor:

    • Power (uterine contractions): maternal effort driving delivery

    • Passage (pelvis): birth canal anatomy and tissue that can expand

    • Passenger (fetus and placenta): baby’s position, placenta, membranes

    • Position/attitude (spine and lie): fetal orientation and position

  • Contractions:

    • Contractions begin gradually, not abruptly; initial contractions are sporadic and irregular (Braxton Hicks) before labor becomes established

    • Increment: rising intensity of a contraction toward the peak

    • Peak (active): contraction reaches its maximum intensity

    • Decrement: contraction subsides

  • Frequency, duration, and interval (resting tone):

    • Frequency: time from the start of one contraction to the start of the next

    • Duration: time from start to end of a single contraction

    • Interval: time between the end of one contraction and the start of the next (uterine resting tone)

  • Assessing contraction intensity:

    • A monitor (electronic fetal monitor) can show timing and pattern but does not reliably measure true contraction intensity

    • Actual contraction intensity is assessed manually by feeling the abdominal fundus: mild (nose), moderate (chin), strong (forehead)

  • Cervix and labor progression:

    • Engaged fetal head: designated by station, with zero being engagement; negative stations are high, positive stations are deeper into the pelvis

    • Dilation: progression from 0 to 10 centimeters; “fingertip” dilation (~1 cm) is an early marker

    • Effacement: thinning of the cervix, expressed as a percentage (0% to 100%); 100% effacement means the cervix is fully thinned

    • In a first-time mother, dilation typically starts after 100% effacement; in multiparous patients, dilation may commence earlier but still follows the pattern of thinning first

  • Fetal positioning and Leopold’s maneuvers:

    • Leopold’s maneuvers at around 36 weeks can help determine fetal lie and position if needed

    • Types of lie/position include longitudinal, oblique, and transverse; typical ideal is longitudinal with occiput anterior (LOA) or occiput posterior (LOP) orientation

    • Positions described with LOA/ROA: left/right (L/R) and occiput (O), face (A/P), or transverse (T); not typically memorized for all positions, but you should recognize that they refer to fetal orientation

  • Breech and other presentations:

    • Breech: frank breech, full breech, footling breech (feet/legs presenting)

    • Most breech presentations are delivered via cesarean section; some cases may attempt external cephalic version (not detailed in the lecture)

  • Membrane rupture and labor induction:

    • ROM = rupture of membranes; AROM = artificial rupture of membranes (e.g., using a crochet-hook-like instrument)
      -ROM often accelerates labor by increasing uterine contractions and removing the barrier to the presenting part

  • Fetal monitoring terminology (NST, etc.):

    • Fetal heart rate baseline and variability are key indicators of fetal well-being

    • Accelerations are brief increases in fetal heart rate, often corresponding to fetal movement or contractions

    • Decelerations are categorized as early, late, variable, or sinusoidal, with different clinical implications:

    • Early decelerations: mirror contractions; head compression; generally benign

    • Late decelerations: lag behind contractions; indicative of uteroplacental insufficiency; may require intervention

    • Variable decelerations: abrupt dips; suggest cord compression (e.g., nuchal cord); can be benign or urgent depending on pattern and accompanying signs

    • Sinusoidal pattern: ominous, associated with hypoxia or anemia; not reassuring

    • Documentation on the strip is critical; mark events with medication administration times as they occur to interpret the strip accurately

Stages of Labor and Postpartum Care

  • Stage 1: Onset of labor to full dilation

    • Latent phase: cervix softens and begins dilating; patient generally comfortable, less intense contractions

    • Active phase: rapid dilation and increased pain; transition (the most intense part) may include tremors, vomiting, and intense discomfort

  • Stage 2: From full dilation to delivery of the baby

    • The clinician checks for the descent of the head; episiotomy may be performed or natural tearing may occur (episiotomy is a surgical incision of the vaginal wall to enlarge the vaginal opening in some cases)

  • Stage 3: Delivery of the placenta

    • Placenta delivery occurs naturally; excessive pulling of the placenta is avoided

  • Stage 4: Postpartum period immediately after delivery

    • Fundal massage is performed to ensure the uterus stays firm and to prevent hemorrhage. A firm fundus indicates good involution; a boggy uterus signals postpartum hemorrhage risk and requires massage and assessment

    • Postpartum assessment includes vaginal discharge (lochia), bleeding amount (should not be excessive), and pain management

  • Practical postpartum care notes:

    • Healthcare providers lead fundal massage to promote firm contractions and reduce hemorrhage risk

    • Documentation of lochia quality, clots, and overall bleeding is essential

    • Patient education on how to continue fundal massage and signs of potential complications after discharge

Practical Examples and Quick Reference Notes

  • Fetal Growth and Measurements:

    • Fundal height correlates with gestational age in many cases after 16 weeks; measurement from pubic symphysis to fundus provides a rough gestational age estimate

  • Estimating Due Date (Naegle’s Rule):

    • EDD ≈ LNMP − 3 months + 7 days

    • Example approximation (illustrative, not a fixed case): If LNMP = 1/25/2024, EDD ≈ 10/25/2024 + 7 days = 11/01/2024 (subject to calendar rounding and leap year considerations)

  • Progestin, Oxytocin, and Methergin (methylergonovine) in clinical context:

    • Progestin: contraceptive use and pregnancy maintenance considerations (as discussed in lecture)

    • Oxytocin: stimulates contractions; used to induce or augment labor

    • Methergin (methylergonovine): uterotonic used to prevent postpartum hemorrhage; dosing and administration require careful monitoring

  • GTT (Glucose Tolerance Test) and glucose changes during pregnancy:

    • Early pregnancy: potential hypoglycemia due to lower glucose levels

    • Mid-to-late pregnancy: risk of gestational diabetes increases; screening with a glucose tolerance test around the mid-second trimester is common

  • Fetal surveillance terminology:

    • NST components include baseline heart rate, variability, accelerations, and decelerations

    • Reactive NST indicates adequate fetal oxygenation and CNS function, while nonreactive NST may require further testing or assessment

  • Pelvic and cervical dynamics:

    • Effacement and dilation are essential to understand labor progression

    • Engagement and station (−3 to +3; 0 is engagement; +3 is crowning) help determine fetal position in the pelvis

  • Important clinical caution: during ultrasound or invasive tests, explain procedures and maintain patient modesty; provide patient education about what to expect (transvaginal ultrasound, amniocentesis, CVS, etc.)

  • Clinical judgment and documentation:

    • Always document timing of interventions (e.g., medication administration) on strips and charts for accurate interpretation

    • Recognize that individual variations exist in anatomy and fetal presentation; use Leopold’s maneuvers and serial exams to assess progress and fetal well-being