Labor and Its Signs

Labor

• Labor is the process of expelling the fetus, membranes, umbilical cord, and placenta from the uterus.
• Labor involves changes in connective tissue, cervical effacement and dilation, and rhythmic uterine contractions.

Premonitory Signs of Labor

• Lightening: The presenting part of the fetus settles into the pelvic inlet.
  • Occurs 10-14 days before labor in primiparas and 1 day before or on the day of labor in multiparas.
  • Signs: Relief of dyspnea, relief of abdominal tightness, increased frequency of voiding, increased varicosities, shooting pains down the legs/leg cramps.
• Increased Braxton Hicks' Contractions: Painless, irregular abdominal contractions that are relieved by walking.
  • Occur 3-4 weeks before labor.
• Sudden Burst of Maternal Energy/Activity: Due to the hormone epinephrine.
• Slight Decrease in Maternal Weight: About 2-3 lb.
  • Attributed to a drop in progesterone levels, leading to fluid excretion.
• Show: Mucus mixed with a small amount of blood from the torn capillaries of the cervix.
  • Differentiate from bleeding.
• Softening/Ripening of the Cervix.
• Rupture of the Bag of Water: An occasional sign.
• Nesting Behavior: A psychosocial sign of approaching labor.
  • The woman prepares for the baby's arrival (sewing diapers, buying a crib, etc.).

True Labor

• Contractions:
  • Regular, progressive, with increasing duration, intensity, and decreasing intervals.
  • Discomfort starts from the back (lumbosacral) radiating to the front.
  • Intensified by walking and enemas.
• Show: Present and increasing.
• Cervix: Open and dilates and effaces.

Pelvic Types

• Gynecoid Pelvis: Most common female pelvis, favorable for vaginal delivery.
• Android Pelvis: Has masculine features (wedge or heart-shaped inlet, reduced outlet).
  • Possible problems during childbirth due to the narrower outlet.
• Anthropoid Pelvis: Long, oval brim with a longer anteposterior diameter than the transverse.
  • Labor usually presents no difficulties.
• Platypelloid Pelvis: Flat pelvis with a kidney-shaped brim, reduced anteposterior diameter, and increased transverse diameter.
  • Potential for cephalopelvic disproportion.

Pelvic Structures

• Innominate Bones: Form the anterior and lateral aspects of the pelvis.
  • Ilium: Upper flaring portion, forms the hip bone.
  • Ischium: Located below the hip joint, supports the body when sitting.
  • Pubes: Front bones, connected by the symphysis pubis.
• Sacrum: Triangular shaped bone forming the posterior portion of the pelvis.
  • Composed of 5 sacral vertebrae.
  • The sacral promontory is an important obstetrical landmark.
• Coccyx: Posterior portion of the pelvis composed of five fused vertebrae.

Stages of Labor

• Latent Phase: Contractions grow stronger, lasting 40-60 seconds, and occur every 3-5 minutes.
  • Lasts approximately 3 hours in nulliparas and 2 hours in multiparas.
  • Increasing vaginal secretions and spontaneous rupture of membranes may occur.
• Active Phase:
  • Contractions become more intense, lasting longer, and cause true discomfort.
  • Emotional Response: Discomfort, perspiration, flushed, fear of losing control, irritable, self-focused.
  • Nursing Responsibilities: Coach woman on breathing and relaxation techniques, administer prescribed analgesics (taking maternal vital signs and fetal heart rate before and after).
• Transition Phase: Contractions reach their peak intensity, occurring every 2-3 minutes, lasting 60-90 seconds, and causing maximum dilatation of 8-10 cm.
  • Membranes usually rupture at full dilatation.
  • Emotional Response: Intense discomfort, nausea and vomiting, feeling of loss of control, discouragement, anxiety, panic, resistance to touch, focus on birthing.
  • Nursing Responsibilities: Reassure the woman that labor is nearing its end, reinforce breathing and relaxation techniques, encourage pant-blow breathing to remove the urge to bear down.

Pushing

• The woman contracts her diaphragm and abdominal muscles while relaxing her pelvic floor and pushes out the contents of the birth canal.
• How to Push: Deep breath, hold, close mouth, chin to chest, bear down.
  • Short pushes are ineffective, prolonged pushes (holding breath > 5 seconds) are not recommended.
• Consequences of Prolonged Pushing:
  • Valsalva Maneuver: Increases intrathoracic and cardiovascular pressure, dangerous for cardiac mothers.
  • Diminished Feto-placental Gas Exchange: Reduced oxygen perfusion across the placenta.
  • Fetal Hypoxia and Distress: Possible complications from reduced oxygen delivery to the fetus.

Cardinal Movements of Labor

• Descent: Downward movement of the biparietal diameter of the fetal head through the pelvic inlet.
  • Full descent occurs when the fetal head extrudes beyond the dilated cervix and touches the posterior vaginal floor.
• Flexion: The fetal head bends forward onto the chest, presenting the smallest AP diameter to the birth canal.
• Internal Rotation: The fetal head rotates to align with the AP diameter of the pelvis.
• Extension: The fetal head extends as it moves past the pubic symphysis.
• External Rotation: The fetal head rotates back to its original position.
• Expulsion: The fetus is delivered.

Postpartum Care

• Lochia: Maternal discharge of blood, mucus, and tissue from the uterus.
  • Lochia Rubra: Bright red, occurs during the first 3 days.
  • Lochia Serosa: Pale, serosanguinous, pinkish to brownish, occurs on days 4-10.
  • Lochia Alba: Whitish or yellowish-white, occurs from day 10-14 or up to 6 weeks postpartum.
• Assess the Patient's Vital Signs:
  • Temperature: Every hour.
  • Blood Pressure, Pulse, and Respirations: Every 15 minutes for an hour, then every 30 minutes for an hour, then every hour as long as the patient is stable.
• Observe for Uterine Atony or Hemorrhage.
• Observe for Untoward Effects from Anesthesia.
• Orient Patient to Surroundings (bathroom, call bell, lights, etc.).
• Encourage Fluid Intake.
• Assess for Urinary Bladder Distention
  • Signs of Full Bladder: Bulging lower abdomen, spongy mass between the fundus and the pubis, displaced uterus from the midline, increased lochia flow.