Maternity and Neonatology Study Guide: Lecture 10

Determining the Estimated Date of Delivery

Naegele’s Rule: This is the standard formula used to calculate the estimated date of delivery (EDD). * Take the first day of the last menstrual period (LMP). * Add 7 days to that date. * Subtract 3 months from the result.
Example Case Study: * Patient's last menstrual period was between June 10 and 15. * Calculation: June 10 + 7 days = June 17. June 17 - 3 months = March 17. * Estimated Date of Delivery = March 17.

Weight Gain During Pregnancy

First Trimester (Weeks 1 to 12): * The patient should gain approximately $1\,lb$ per month. * Total weight gain for the first trimester should be $3\,lbs$ .
Second and Third Trimesters: * The patient should gain $1\,lb$ every week.
Total Ideal Weight Gain: * The total ideal weight gained during the entire pregnancy is $28\,lbs$ $\pm 3\,lbs$ . * The acceptable range is between $25\,lbs$ and $31\,lbs$ .
The Alternative Method (Quick Calculation): * A "quick and dirty" way to determine the ideal weight at a specific point in gestation is: $\text{Number of weeks gestation} - 9$ .
Assessing Weight Gain Deviations: * Within $\pm 1$ to $2\,lbs$ of ideal: The patient is WNL (Within Normal Limits). * Within $\pm 3\,lbs$ of ideal: The nurse must assess the patient. * Within $\pm 4\,lbs$ or more of ideal: This indicates trouble; the nurse must perform a Biophysical Profile (BPP) on the fetus.

Weight Gain Practice Questions

Question 1: A woman is in her 28th week of gestation and has gained $22\,lbs$ . What is your impression? * Long Method: First trimester (12 weeks) = $3\,lbs$ . Current week (28) - 12 weeks = 16 weeks remaining. At $1\,lb$ per week, that is $16\,lbs$ . Total ideal = $3 + 16 = 19\,lbs$ . The patient has gained $3\,lbs$ extra. Impression: Assess the patient. * Short Method: $28 - 9 = 19\,lbs$ . Gained $22$ , which is $3\,lbs$ over. Impression: Assess the patient.
Question 2: A pregnant woman at 31 weeks gestation has gained $15\,lbs$ . What is your impression? * Short Method: Ideal weight = $31 - 9 = 22\,lbs$ . * Comparison: $22 - 15 = 7\,lbs$ less than ideal. * Impression: There is trouble; the nurse needs to assess the biophysical profile (BPP) on the fetus.

Fundal Height

Palpation Milestones: * The fundus cannot be palpated until week 12. * Week 12: The fundus is located midway between the umbilicus and the pubic symphysis. * Week 20 to 22: The fundus can be palpated at the level of the umbilicus.
Clinical Significance: * Trimester Identification: Allows the examiner to determine which trimester the pregnancy is in (useful if the patient is unconscious). * Diagnostic Utility: A fundus that is significantly larger than normal for the gestational age may indicate a molar pregnancy.

Signs of Pregnancy

Positive Signs (Definitive): 1. Fetal skeleton visible on x-ray. 2. Presence of the fetus on an ultrasound. 3. Auscultation of the fetal heart using a Doppler. 4. Examiner palpates fetal movement (fetal outline). Note: This must be the examiner, not the mother's report.
Maybe Signs (Presumptive/Probable): 1. Positive hCG tests (Urine/Blood): These are not definitive as they can result from other conditions, such as cancer. 2. Chadwick Sign: Cervical color change to cyanosis (bluish discoloration of the vulva, vagina, and cervix). 3. Goodell Sign: Softening of the cervix ("Good and Soft"). 4. Hegar Sign: Softening of the lower uterine segment.
Mnemonic for Maybe Signs: Chadwick \rightarrow Goodell \rightarrow Hegar. They are in alphabetical order and move anatomically upward from the vulva/vagina/cervix to the uterus.

Gestational Milestones and Ranges

Fetal Heart Rate (FHR): Can be heard first between 8 and 12 weeks gestation.
Quickening (Baby Kicks): First felt between 16 and 20 weeks gestation.
Application Questions: * "When would you first?": Use the earliest date (Fetal Heart: 8 weeks; Quickening: 16 weeks). * "When would you most likely?": Use the midway date (Fetal Heart: 10 weeks; Quickening: 18 weeks). * "When should you [milestone] by?": Use the latest date (Fetal Heart: 12 weeks; Quickening: 20 weeks).

Prenatal Visit Schedule

Once a Month: Until week 28.
Every Other Week: Between week 28 and week 36.
Once a Week: After week 36 until delivery or week 42.
Week 42: If the patient has not delivered, labor can be induced or a C-section performed.
Question: If a woman visits for her 12th-week checkup, when is the next visit? * Answer: 16 weeks (4 weeks/1 month later).

Laboratory Values and Physiological Changes

Hemoglobin (Hb): Hb levels naturally fall during pregnancy. While the normal female range is $12$ to $16\,g/dL$ , pregnant women tolerate lower levels. * First Trimester: Normal down to $11\,g/dL$ . * Second Trimester: Normal down to $10.5\,g/dL$ . * Third Trimester: Normal down to $10\,g/dL$ .
UWorld Specific Hb Thresholds: * 1st & 3rd Trimester: $11\,g/dL$ . * 2nd Trimester: $10.5\,g/dL$ . * Anemia Evaluation: Required if Hb is under $9\,g/dL$ .

Management of Common Pregnancy Complaints

Morning Sickness: * Occurs primarily in the 1st trimester. * Treatment: Eat dry carbohydrates before getting out of bed (not just before breakfast).
Urinary Incontinence: * Seen in the 1st and 3rd trimesters. * Treatment: Patient should void every 2 hours from the start of pregnancy until 6 weeks postpartum.
Difficulty Breathing (Dyspnea): * Seen in the 2nd and 3rd trimesters. * Treatment: Assume the tripod position (leaning forward with hands on knees or a desk/table).
Back Pain: * Seen in the 2nd and 3rd trimesters. * Treatment: Perform pelvic tilt exercises.

Labor and Birth Fundamentals

Valid Sign of Labor: The onset of regular and progressive contractions.
Dilation: The opening of the cervix from $0$ to $10\,cm$ .
Effacement: The thinning of the cervix, from thick to $100\%$ effaced (paper-thin).
Station: The relation between the fetal presenting part and the mother’s ischial spines (the narrowest part of the pelvis). * Positive Numbers: The baby has passed through the tightest squeeze. * Negative Numbers ( $-3, -2, -1$ ): The baby cannot get through vaginally and may require a C-section. * Engagement: Station $0$ (presenting part is at the ischial spines).
Lie: The relationship between the spine of the mother and the spine of the baby. * Vertical Lie: Spines are parallel; compatible with vaginal birth. * Transverse Lie (Perpendicular): "T for Trouble," requires a C-section.
Presentation: The most common are ROA (Right Occiput Anterior) or LOA (Left Occiput Anterior). If forced to choose, pick ROA.

Stages and Phases of Labor

Stage 1: Onset of Labor (Cervical Dilation and Effacement). Divided into 3 phases: 1. Latent (Phase 1): Dilation $0$ to $4\,cm$ . Contractions $5$ to $30$ minutes apart, lasting $15$ to $30$ seconds. Intensity: Mild. 2. Active (Phase 2): Dilation $5$ to $7\,cm$ . Contractions $3$ to $5$ minutes apart, lasting $30$ to $60$ seconds. Intensity: Moderate. 3. Transition (Phase 3): Dilation $8$ to $10\,cm$ . Contractions $2$ to $3$ minutes apart, lasting $60$ to $90$ seconds. Intensity: Strong.
Stage 2: Delivery of the Baby.
Stage 3: Delivery of the Placenta.
Stage 4: Recovery. Lasts 2 hours until bleeding stops.
Postpartum Start: Officially begins 2 hours after the delivery of the placenta.

Nursing Priorities and Uterine Dynamics

Priorities by Stage/Phase: * First Stage (Phase 2/Active): Pain management. * First Stage (Phase 3/Transition): Checking dilation, breathing, and pain management. * Second Stage: Clearing the baby’s airway. * Third Stage: Assessing the placenta for smoothness/intactness and ensuring a 3-vessel umbilical cord (not 2).
Uterine Contraction Safety Limits: * Contractions should be no longer than $90$ seconds and no closer than $2$ minutes. * Exceeding these limits defines Uterine Tetany or Uterine Hyperstimulation; the nurse must stop Pitocin if running.
Assessment of Contractions: * Frequency: Measured from the beginning of one contraction to the beginning of the next. * Duration: Measured from the beginning to the end of a single contraction. * Intensity: Purely subjective; assessed by palpating the fundus with the pads of the fingers.

Labor Complications and Protocols

Protocol for "OP" (Occiput Posterior/Back Pain): "OP = Oh Pain". 1. Position: Move mother to Knee-Chest position. 2. Push: Use a fist to apply counter-pressure to the sacrum.
Protocol for Prolapsed Cord: 1. Push: Push the fetal head up and off the cord. 2. Position: Place mother in Knee-Chest or Trendelenburg position. 3. Preparation: Prepare for immediate C-section.
Protocol for All Other Complications (Tetany, Hypotension, Toxemia, etc.): Use the mnemonic "LION". * L: Left side (reposition the mother). * I: IV (start/increase fluids). * O: Oxygen. * N: Notify Health Care Provider (HCP). * Critical Order: If Pitocin (Pit) is running, stop it first, then implement LION.
Systemic Pain Medication Administration: * Do not administer systemic pain meds if the baby is likely to be born at the time the medication reaches its peak. * Scenario 1: Primigravida at $5\,cm$ wants IV pain med. Action: Hold the medication; the peak occurs in $15$ to $30$ minutes, coinciding with delivery. * Scenario 2: Multigravida at $8\,cm$ wants IM pain med. Action: Do not administer medication.