Nursing Management During Pregnancy - Comprehensive Notes

Prenatal Care: Goals and Overview

• Early prenatal care is crucial for the health of the woman and the unborn baby

• Best strategy: seek care before conception

• Goals of prenatal care:

  • Optimize the health of the woman

  • Optimize the health of the fetus

  • Increase the odds that the fetus is born healthy to a healthy mother

• Focus areas include risk identification, history taking, fetal well-being assessment, and recognizing danger signs

Teratogens: Definition, Timing, and Categories

• Teratogens are substances or processes that can cause birth defects

• Severity depends on two factors:

  • Timing of exposure during fetal development

  • Type of teratogen

• Embryonic period is the most critical for teratogenic effects because organ systems are forming

• Teratogens fall into three categories: ingested, infectious, or environmental

• Ingested examples:

  • Dilantin (phenytoin), chemotherapy agents, tetracycline, alcohol, smoking

• Infectious examples:

  • Varicella, rubella, cytomegalovirus (CMV)

• Environmental examples:

  • Radiation exposure, mercury exposure

Medication Categories in Pregnancy (FDA/labeling-style categories)

• Medications are categorized as A, B, C, D, X in terms of fetal risk

  • A and B: typically no real risk involved

  • C: risk is questionable or uncertain

  • D and X: proven risk to the fetus; should be avoided if possible

• In life-threatening situations, category D may be used after patient-practitioner discussion

• General rule: all pregnant women should avoid any medication without consulting their physician first

Other Risk Factors for Adverse Pregnancy Outcomes

• Isotretinoin (Accutane) or similar acne meds (including some topical forms)

• Alcohol misuse

• Antiepileptic drugs

• Diabetes

• Folic acid deficiency

• Hepatitis B, HIV/AIDS

• Hypothyroidism

• Maternal phenylketonuria (PKU) or phenylalanine crosses placenta via aspartame

• Rubella infection history

• Obesity

• Oral anticoagulants

• Sexually transmitted infections (STIs)

• Smoking

First Prenatal Visit: Timing, Purpose, and Major Components

• Ideally occurs as soon as the woman suspects pregnancy (missed period/late period trigger)

• Often the longest visit; establishes baseline data for all future visits

• Major element: obstetrical history

• Components discussed below in detail

Obstetrical History: Gravid/Para and GTPAL

• Gravid: state of being pregnant; refers to the pregnant woman and the number of pregnancies

• Para: number of deliveries at 20 weeks or greater gestation

• Nulligravida: never been pregnant

• Primigravida: pregnant for the first time

• Multigravida: pregnant more than once

• GTPAL system:

  • G: Gravida – number of pregnancies

  • T: Term deliveries – 38 to 42 weeks gestation

  • P: Pre-term deliveries – greater than 20 weeks but before 37 completed weeks

  • A: Abortions – loss of pregnancy before 20 weeks or viability

  • L: Living children – number of currently living children

Medical/Surgical History and Other History Components

• Major medical problems (e.g., heart disease, diabetes) that require closer surveillance

• Prenatal records should list all medications (prescription, OTC, herbal remedies)

• Determine risk factors for infectious diseases and immunization status; assess HIV risk

• Family history for potential genetic testing needs

• Ethnicity: important due to carrier status for certain conditions (e.g., sickle cell anemia frequently carried in African-Americans)

• Social history: environmental factors influencing pregnancy (social support, housing, nutrition, alcohol/drug use, exposure to toxins)

Physical Exam and Pap Smear Considerations

• Physical exam performed by the practitioner; nurse may assist (e.g., Pap smear)

• Pap smear in pregnancy can cause small vaginal bleeding; inform patient that this can be normal, but excessive bleeding should be reported

• Prior pregnancies with miscarriages/abortions/anxiety considerations may require extra support

• Pelvic size and shape measurements may be taken to assess fetal progression

Laboratory Tests at First Visit

• Serum pregnancy test to confirm pregnancy

• CBC to assess anemia and overall status

• Blood type and antibody screen (Rh status) for compatibility

• Infectious disease testing: HIV, HBV, STI screening as indicated

• Rubella titer

• Urine screening and culture for bacteria

• Pap smear (to rule out cervical pathology)

• Glucose screening (baseline or risk-based as indicated)

Due Date Estimation (Estimated Date of Delivery, EDD)

• Terminology:

  • EDD: Estimated Date of Delivery

  • EDC: Estimated Date of Confinement (older term)

  • “Due date” is commonly used

• Nagel's Rule: a common method to calculate EDD

  • Calculation approach using last menstrual period (LMP):

  • Subtract 3 months from LMP, then add 7 days

  • Alternatively, add 280 days to the LMP date

  • Example:

  • If LMP = August 8, subtract 3 months → May 8, add 7 days → May 15

  • Therefore, EDD = May 15

  • Formally: $ext{EDD} = ext{LMP} + 280 ext{ days} = ( ext{LMP} - 3 ext{ months}) + 7 ext{ days}$

• Gestational wheel: a visual tool around which you align the LMP to determine EDD

• Ultrasound can also be used to determine the most accurate due date, especially if there is uncertainty with LMP

Subsequent Prenatal Visits: Schedule and Routine Assessments

• Normal pregnancy visit schedule (adjust for high-risk cases):

  • Up to 28 weeks: every 4 weeks

  • 29–36 weeks: every 2 weeks

  • 37 weeks to delivery: weekly

• At each visit, perform:

  • Weight

  • Blood pressure

  • Urine protein screening

  • Glucose screening (when indicated)

  • Fetal heart rate check

• Ongoing assessment of danger signs and fetal well-being indicators:

  • Question about danger signs (see list later)

  • Fetal movement monitoring

  • Contractions

  • Bleeding

  • Membrane rupture

• Pelvic exam frequency: not routinely repeated until near delivery

• Fundal height measurements to assess fetal growth/progress

Routine Screening and Timing During Pregnancy

• 15–20 weeks: Maternal serum alpha-fetoprotein (MSAFP) screening

• 24–28 weeks: Gestational diabetes screening for all women

• 28 weeks: Rh-negative mothers screened for antibodies; administer anti-D immunoglobulin (RhoGAM) if indicated; if baby Rh-positive, plan RhoGAM after delivery

• 35–37 weeks: Group B streptococcus (GBS) screening; if positive, administer antibiotics during delivery to prevent neonatal infection

Assessment of Fetal Well-Being

Fetal Kick Counts

• Can be performed at home, work, or elsewhere

• Fetal movement typically felt starting around 16–20 weeks

• Procedure: pick a time of day to relax; count each movement (kick or position change); continue until 10 movements are counted

• Normal expectation: at least 10 movements in 2 hours

• If >2 hours pass or movement is not felt, contact the healthcare provider

Ultrasound

• Uses high-frequency sound waves to visualize fetal and maternal structures

• Purposes:

  • Estimate gestational age

  • Observe fetal growth and anatomy

  • Diagnose pregnancy complications

• Approaches:

  • Transabdominal: ultrasound probe on the abdomen; full bladder may help early visualization; a wedge under the hip reduces supine hypotensive syndrome; gel applied to abdomen

  • Transvaginal: ultrasound probe inserted into the vagina; provides clearer images; used in earlier pregnancies

• Positioning considerations: lithotomy position with draping for privacy during transvaginal scans

Maternal Serum Alpha-Fetoprotein (MSAFP) Screening

• AFP is a protein produced by the fetus; small amounts cross into maternal circulation

• Timing: typically measured at 16–20 weeks gestation

• Purpose: screen for neural tube defects (e.g., anencephaly, spina bifida)

• Interpretation: abnormal results require follow-up ultrasound and/or amniocentesis

• Note: ~90% of pregnancies with abnormal MS AFP still result in healthy babies; results create important emotional considerations for parents

Triple Marker / Multip marker Screening

• Combines MS AFP with two other hormones: human chorionic gonadotropin (hCG) and unconjugated estriol

• Purpose: increase sensitivity and accuracy for detecting chromosomal abnormalities

• Interpretation:

  • Low MS AFP with low estriol and elevated hCG suggests Down syndrome

  • Low levels of all three markers suggest trisomy 18 (Edward syndrome)

Amniocentesis (Diagnostic Test)

• Diagnostic procedure: needle aspiration of amniotic fluid

• Timing: usually 15–20 weeks; generally not performed before 12 weeks due to risk

• Process:

  • Ultrasound guides needle to a pocket of amniotic fluid

  • A spinal needle (20–22 gauge) is used; first 0.5 mL is discarded to avoid maternal cell contamination

  • Approximately 20 mL of fluid is collected for testing

  • Fetal heart rate monitored by ultrasound during the procedure

  • Post-procedure: patient rests; monitor vital signs and watch for leakage, vaginal bleeding, cramping, or contractions

  • Results: typically available in 2–3 weeks; highly accurate

• Risks: small risks of spontaneous abortion, fetal injury, chorioamnionitis (infection of fetal membranes)

• Post-procedure care: Rh-negative mothers should receive RhoGAM

Chorionic Villus Sampling (CVS)

• Diagnostic procedure for placental tissue to obtain fetal cells for chromosomal analysis

• Timing: typically 8–12 weeks gestation (earlier than amniocentesis allows earlier decision-making)

• Procedure:

  • Ultrasound confirms placental location and gestational age

  • Patient positioned in lithotomy; vagina and cervix cleansed with antiseptic

  • A small catheter is inserted through the cervix to obtain placental tissue (transvaginal approach)

  • Alternatively, a transabdominal approach with needle can be used

  • Faster results than amniocentesis

• Indications: same as amniocentesis (e.g., risk of chromosomal abnormalities)

Indications for Amniocentesis and CVS (General Guidelines)

• Advanced maternal age (> 35 years)

• Previous offspring with chromosomal anomalies

• History of recurrent pregnancy loss

• Ultrasound-detected fetal anomalies

• Abnormal MSAFP, triple marker, or multimarker screen

• Parental carriers of recessive genetic traits (e.g., cystic fibrosis, sickle cell disease, Tay-Sachs)

Non-Stress Test (NST)

• Non-invasive test to assess fetal well-being

• No special preparation required

• Method: fetal heart rate monitor placed on the abdomen; may use a handheld marker for movements

• Interpretation: reactive NST requires at least two accelerations of the fetal heart rate above baseline, each at least $15 ext{ beats per minute (bpm)}$ above baseline and lasting at least $15 ext{ seconds}$ within a 20-minute period

• If fewer than two accelerations occur within 20 minutes, the NST is considered non-reactive; monitoring may continue for another 20 minutes due to fetal sleep cycles (~20 minutes)

Contraction Stress Test (CST)

• Assesses fetal response to contractions (stress of reduced uteroplacental blood flow)

• Method: electronic fetal monitoring (EFM) to watch fetal response during contractions

• How contractions are produced:

  • Spontaneous contractions

  • Nipple stimulation to induce contractions

  • IV Pitocin to induce contractions

• Goal: achieve three contractions of at least 40 seconds duration within a 10-minute window

• Interpretation:

  • Negative CST: no late decelerations with contractions (favorable)

  • Positive CST: presence of late decelerations indicating potential fetal compromise

Biophysical Profile (BPP)

• Composite test combining NST and ultrasound assessments

• Five variables measured:

  • NST (fetal heart rate accelerations)

  • Ultrasound assessment of: breathing movements, body movements, fetal tone, and amniotic fluid volume

• Scoring: each variable scored 0 (absent/abnormal) or 2 (present/normal); maximum total score = 10

• Interpretation:

  • 8–10: fetal well-being

  • 6: possible fetal asphyxia; closer monitoring or additional testing recommended

  • 4: probable fetal asphyxia; delivery may be considered

  • 0–2: ominous; immediate delivery may be warranted

Danger Signs in Pregnancy (When to Seek Help)

• Fever or severe, unrelieved vomiting

• Headache unrelieved by analgesics (e.g., Tylenol)

• Visual disturbances (blurred vision or spots before the eyes)

• Epigastric or abdominal pain

• Sudden weight gain or edema of hands/face

• Vaginal bleeding

• Painful or frequent urination (dysuria)

• Sudden gush or continuous leakage of fluid from the vagina

• Decreased fetal movement

• Signs of preterm labor: uterine contractions, lower dull backache, pelvic pressure, menstrual-like cramps, increased vaginal discharge

• A general sense that something isn’t right should prompt evaluation

Ethical, Practical, and Real-World Considerations

• Informed consent is required for invasive tests like amniocentesis and CVS

• Counseling and support are important when results are abnormal or ambiguous (emotional impact on parents and families)

• Decisions about invasive testing depend on balance of risks, benefits, and patient values

• Importance of patient education about normal variations and expected signs during pregnancy

Quick Reference: Key Formulas, Timelines, and Milestones

• Due date estimation (Nagel's Rule):

  • Formulas:

  • $ext{EDD} = ext{LMP} + 280\text{ days}$

  • $ext{EDD} = ( ext{LMP} - 3\text{ months}) + 7\text{ days}$

  • Example: LMP = August 8 → EDD = May 15

• Fetal movement expectation (Kick counts): at least 10 movements in 2 hours

• NST criteria for a reactive test: ≥2 accelerations, each ≥$15\text{ bpm}$ above baseline, lasting ≥$15\text{ seconds}$ within 20 minutes

• CST target contractions: 3 contractions of ≥40 seconds within 10 minutes

• BPP scoring: 0–2 (ominous), 4 (probable asphyxia), 6 (possible asphyxia), 8–10 (normal well-being)

Summary of Practical Implications

• Comprehensive prenatal care integrates history, physicals, labs, imaging, and fetal surveillance

• Timely screening tests and appropriate follow-up enable early detection and management of potential problems

• Clear communication with patients about risks, test purposes, and possible outcomes is essential for informed decision-making and reducing anxiety

• Ethical considerations (informed consent, counseling) are central to management of invasive diagnostics and abnormal screening results