Week 4 part 2: labour & delivery

  • Explain the normal processes of childbirth:

    • Premonitory signs

    • Mechanisms of birth

    • Stages and phases of labour

  • Differentiate between prelabour and true labour.

Settings for Childbirth

  • Hospitals

  • Freestanding birth centres

  • Home

  • Patients should have the autonomy to choose where they wish to give birth.

Signs of Impending Labour

  • Indicators that labour may begin soon:

    • Braxton Hicks contractions (practice contractions)

    • Lightening (the fetus drops into the pelvis)

    • Backache

    • Cervical changes

    • Increased vaginal discharge (bloody show)

    • Energy surge (nesting instinct)

    • Weight loss

    • Flu-like symptoms

    • Rupture of membranes (water breaking)

The Five Ps of the Birth Process

  1. Powers

    • Uterine contractions are vital in the labour process:

      • They cause the cervix to efface (thin) and dilate (open), allowing the fetus to descend through the birth canal.

    • Phases of contractions:

      • Frequency (how often contractions occur)

      • Duration (how long contractions last)

      • Intensity (strength of contractions): measured as mild, moderate, or strong.

    • Pushing combines the power of uterine contractions and voluntary maternal efforts to propel the fetus downward.

  2. Passage

    • The birth canal (passage) includes:

      • Bony pelvis: Four types of pelvic shapes:

      • Gynecoid (optimal for childbirth)

      • Android

      • Anthropoid

      • Platypelloid

      • Soft tissues: Will yield more easily with prior vaginal births, aiding in the comfort of contractions and pushing.

  3. Passenger

    • The passenger comprises the fetus, placenta, and amniotic membranes.

    • Fetal head structure plays a crucial role in labour:

      • Sutures and fontanelles (anterior and posterior) allow for changes in shape (moulding) as the head moves through the birth canal.

    • Fetal lie: Orientation of the fetus in relation to the pregnant person's spine.

      • Types: Longitudinal (preferred) or transverse.

    • Fetal attitude: Relation of fetal body parts to each other, with flexion being the most favourable for vaginal birth.

    • Fetal presentation: The part of the fetus entering the pelvis first (e.g., head or breech)

      • Most common presentations include: Vertex, brow, face, breech (frank, full, footling), and transverse.

  4. Position

    • Maternal positioning has significant effects on labour:

      • Upright positions (walking, squatting, sitting, kneeling) often lead to shorter labours.

      • Frequent position changes during labour are encouraged. The supine position is not beneficial.

  5. Psyche

    • The mental state of the labouring individual can heavily influence the progress of labour:

      • A relaxed and positive mindset may improve coping with discomfort.

      • Anxiety and fear can lead to the secretion of catecholamines, which may inhibit uterine contractions and divert blood flow.

    • Cultural and individual values will shape experiences and coping mechanisms regarding childbirth.

Comparison of Prelabour and True Labour

Feature

Prelabour (Prodromal Labour)

True Labour

Contractions

Gradually develop into a regular pattern; irregular or do not increase

Become stronger and more effective with walking; regular pattern

Discomfort

Felt in the lower back and abdomen, often like menstrual cramps

Felt in the abdomen and groin

Bloody show

Often present

Usually not present

Cervix changes

No change in effacement or dilation

Progressive effacement and dilation occur

When to Go to the Hospital or Birth Centre

  • Signs you should go include:

    • Increase in frequency, duration, and intensity of contractions.

    • Inability to cope at home anymore.

    • Ruptured membranes and group B streptococcus (GBS) status presence.

    • Presence of bleeding other than a bloody show.

    • Decreased fetal movement.

    • Any other concerning situations.

Inspection of Amniotic Fluid

  • Assessments of amniotic fluid include:

    • Color: Normal is clear; green may indicate the fetus has passed meconium.

    • Odour: Any unusual odour may indicate infection.

    • Amount:

      • Scant (trickle)

      • Moderate (approximately 500 mL)

      • Large (≥ 1,000 mL)

  • After membranes rupture, assess fetal heart rate (FHR) for 1 minute.

  • Utilize the Nitrazine test for further evaluation.

Fetal Health Surveillance

  • Key components include evaluating:

    • Frequency, duration, and intensity of uterine contractions (assessed in 10-minute intervals).

    • Fetal heart rate (FHR) via intermittent auscultation or continuous electronic fetal monitoring (EFM).

Continuous Electronic Fetal Monitoring (EFM)

  • Recommended for high-risk pregnancies and records FHR continuously.

  • Safety alert regarding monitoring frequency:

    • Every 15 to 30 minutes in the first stage of labour.

    • Every 5 minutes or immediately after each contraction in the second stage.

The Labour Process

#1 First Stage of Labour (longest stage)

  • Divided into three phases:

    • Latent Phase: Duration 4-6 hours; cervix dilates 1-4 cm; contractions every 20 minutes down to 5 minutes, lasting 15-40 seconds at mild to moderate intensity.

    • Active Phase: Duration 2-6 hours; cervix dilates 4-7 cm; contractions every 2-5 minutes, lasting 40-60 seconds at moderate to firm intensity. - Behaviours: apprehensive, anxious, introverted, perspires, facial flushing, may request pain relief, may need epidural or analgesia

    • Transition Phase: Duration 30 minutes to 2 hours; cervix fully dilates to 10 cm; contractions every 2-3 minutes, lasting 60-90 seconds at firm intensity. Behaviours: irritable, may want to give up, restless, tremor of legs, may request medication, nausea, vomitting

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Care and Management of Labour

  • The nurse should guide the labouring individual on positions and techniques, ensuring supportive measures are in place.

  • Assist in coping strategies and provide ongoing evaluation and adjustment of the care plan as needed.

Stages of Labour

#2 Second Stage: Expulsion of the fetus with contractions approximately 1.5-3 minutes apart, lasting 60-80 seconds at firm intensity. Episiotomy may be necessary.

  • Cervix dilation is 10 cm

  • Contractions: q 1 1/2- 3 mins apart

  • Duration: 60 – 80 seconds

  • Intensity: firm

  • Episiotomy may be performed if needed

  • Behaviours: bulging perineum. May pass stool, uncontrollable urge to push, states baby is coming. Exhaustion after each contraction. May find it difficult to focus on directions

#3 Third Stage: Duration lasts between 5-30 minutes; expulsion of the placenta. Nurses assess blood loss, monitor vital signs, and facilitate newborn care.

  • Duration: 5 – 30 minutes

  • Contractions – intermittent

  • Intensity – mild to moderate

  • Umbilical cord is cut

  • Placenta is delivered

  • Uterus contracts to size of grapefruit

  • Episiotomy/laceration is sutured

  • Behaviours: Elation, relief, tremors, tears

#4 Fourth Stage: Recovery phase focusing on uterine tone, Lochia assessment and supporting maternal/newborn bonding.

  • Uterus remains midline, firmly contracted at or below umbilicus

  • Lochia rubra saturates perineal pad (no more than one pad per hour)

  • Cramping may occur

  • Birthing person may have shaking chills related to thermoregulation response

  • Behaviours: get acquainted period between birthing person, infant, partner

    First period of reactivity - breastfeed infant

Cesarean Delivery Overview

  • Incision types in cesarean deliveries include:

    • Vertical through skin and uterus.

    • Horizontal through the skin (first skin crease) and uterus.

Maternal Adaptations to Labour

  • Changes manifest through multiple systems:

    • Hematologic and cardiovascular involvement.

    • Respiratory alterations.

    • Adjustments in renal and gastrointestinal function

Mechanisms of Labour: Cardinal Movements

The cardinal movements describe how the fetus navigates through the maternal pelvis during labour, allowing safe delivery.

  1. Descent

    • The fetal presenting part (usually the head) moves downward into the maternal pelvis.

  2. Engagement

    • Occurs when the presenting part reaches the level of the ischial spines (station 0).

    • Indicates the widest part of the fetal head has passed through the pelvic inlet.

  3. Flexion

    • The fetal head flexes so the chin touches the chest.

    • Contractions assist by guiding the head through the pelvic curve.

  4. Internal Rotation

    • As the fetus enters the pelvis, the occiput (back of the head) is usually oriented toward the right or left side.

    • The shape of the maternal pelvis causes the head to rotate so the occiput aligns under the symphysis pubis.

  5. Extension

    • Once the fetal head reaches the vaginal opening, it extends to pass under the pubic symphysis and out of the birth canal.

  6. Restitution and External Rotation

    • After the head is born in extension, it spontaneously turns (restitutes) to align with the shoulders.

    • Shoulders rotate to fit through the pelvis.

  7. Expulsion

    • The anterior shoulder is delivered first, followed by the posterior shoulder, and then the rest of the body.

Fetal Heart Rate (FHR) & Fetal Respirations

Fetal Heart Rate:

  • Normal range: 110–160 bpm during pregnancy.

  • Decelerations may occur during contractions due to temporary reduced placental blood flow—important to monitor.

Fetal Respirations:

  • Passage through the birth canal helps clear fetal lungs and mucous.

  • Maternal tissue compression assists in expelling fluid from respiratory passages.

  • C-section babies may require more suctioning, as they miss the “vaginal squeeze” benefit.

Maternal Physiologic Changes During Labour

Hematologic System:

  • Increased oxygen demand, similar to vigorous aerobic activity.

  • Cardiac output:

    • Moderate increase during first stage.

    • During second stage (pushing), can increase 40–50% above pre-labour levels.

  • Pulse: Often elevated due to exertion, dehydration, and exhaustion.

  • Blood pressure: Usually remains stable.

Respiratory System:

  • Respirations increase with pain and exertion.

  • Higher oxygen demand raises risk of hyperventilation, dry mouth, and dehydration.

Renal System:

  • Bladder: Pressure from presenting part may cause overfilling, decreased sensation to void, and edema.

  • Impact: Full bladder can slow labour; intermittent catheterization may be needed.

Gastrointestinal System:

  • Labour delays gastric emptying, increasing risk of nausea and vomiting.

  • Current guidelines allow clear fluids during labour.

C-Section: What to Expect & Nursing Role

Monitoring:

  • Surgical dressing: Check for bleeding or signs of infection.

  • Pain: Assess frequently; manage with prescribed analgesics.

  • Output: Monitor urine (catheter if present) and bowel function.

  • Gas pain: Common due to anesthesia; encourage ambulation if possible.

  • Blood clots: Monitor calves for swelling, redness, warmth (DVT risk).

Mobility & Assistance:

  • Encourage early ambulation when safe.

  • One-to-one assistance for initial bathroom trips.

Patient Education:

  • Expect some gas pain and limited mobility.

  • Importance of monitoring incision, pain, and signs of complications.

Fetal Heart Rate (FHR) & Electronic Monitoring

Normal Baseline FHR:

  • 110–160 beats/min

Variability:

  • Fluctuations above and below baseline, giving a sawtooth appearance.

  • Along with accelerations and decelerations, variability is a normal finding.

  • Abnormal findings require specialized perinatal training.

Monitoring Guidelines:

  • Intermittent monitoring with Doppler is best practice unless continuous monitoring is indicated due to pregnancy/labour concerns.

Electronic Fetal Monitoring (EFM):

  • Records FHR in the upper grid and uterine contractions in the lower grid.

  • Sawtooth FHR tracing reflects constant variability.

  • Grid details:

    • Dark black lines: 1-minute intervals

    • Light black lines: 10-second intervals