stages of labor (textbook)

first stage

• From 0 to 10 cm dilation

• begins with the first true contraction and ends with full dilation of the cervix

• fetal membranes usually rupture but may have burst earlier or possibly even remain intact until birth

• patients usually perceive the visceral pain of diffuse abdominal cramping and uterine contractions

  • Pain mainly arises from cervical dilation, stretching of the lower uterine segment, and stretching of these structures during contractions.

Latent phase

• begins with the start of regular contractions and ends when rapid cervical dilation begins

  • Sedation can increase the duration of this phase

• mom may be talkative and perceive contractions to be similar to menstrual cramps

• may remain at home during this phase

• Cervical dilation from 0 to 6 cm

• Cervical effacement from 0% to 40%

• Nullipara can last up to 20 hours; multipara can last up to 14 hours

• Contraction frequency every 5–10 minutes

• Contraction duration 30–45 seconds

• Contraction intensity mild to palpation

  • Intensity is assessed by pressing the fundus during a contraction; if it dents at the peak of the contraction, then the contraction is mild

Active phase

• begins with an increased rate of cervical dilation (end of latent phase) until the completion of cervical dilation

• fetus descends farther in the pelvis

• mom becomes more intense and inwardly focused, absorbed in the serious work of labor, limiting interactions with those in the room

  • If they attended childbirth classes, they will use relaxation and paced breathing techniques to manage contractions.

• Cervical dilation from 6 to 10 cm

• Cervical effacement from 40% to 100%

• Nullipara lasts up to 6 hours; multipara lasts up to 4 hours

• Contraction frequency every 2–5 minutes

• Contraction duration 45–60 seconds

• Contraction intensity moderate to strong by palpation

second stage (expulsive stage)

• From complete dilation (10 cm) and effacement to birth of the newborn

• can last from minutes up to 3 hours

• Parity, delayed pushing, use of epidural analgesia, maternal body mass index, birth weight, pelvis shape, occiput posterior position, and fetal station at complete dilation all have been shown to affect the length of this stage

  • longer duration = adverse maternal outcomes and traumatic complications

    • maternal outcomes: higher rates of puerperal infection, fetal acidemia, shoulder dystocia, bony fractures, nerve palsies, scalp hematomas, and anoxic brain injuries

    • traumatic complications: uterine rupture or hemorrhage, vaginal laceration, cervical laceration, third- and fourth-degree perineal lacerations, amniotic fluid embolism, and death

• mom feels more in control and less irritable and agitated

• maternal urge to push is generally felt when there is direct contact of the fetus to the pelvic floor

  • Stretch receptors in the vagina, rectum, and perineum detect fetal pressure descending in the birth canal, triggering the urge to push along with increased abdominal pressure.

Pelvic phase: period of fetal descent

Perineal phase: period of active pushing

• Nullipara lasts up to 3 hours; multipara lasts up to 2 hours

• Contraction frequency every 2–3 minutes or less

• Contraction duration 60–90 seconds

• Contraction intensity strong by palpation

• Strong urge to push during the later perineal phase

third stage

• starts after the newborn is born and ends with the separation and birth/delivery of the placenta

• Continued uterine contractions cause the placenta to be expelled

• lasts 5-30 minutes

• If stable, the newborn bonds with mom through touch, holding, and skin-to-skin contact

  • ideal placement for baby is moms abdomen or chest which promotes a positive transition from intrauterine to extrauterine life

• average blood loss during a spontaneous vaginal delivery is less than 500 mL

Placental separation: detaching from uterine wall

• the result of a decrease in uterine surface area while contractions continue strongly

Placental expulsion: coming outside the vaginal opening

fourth stage (restorative stage or immediate postpartum period)

• 1-4 hours after the birth of the newborn

• begins once the placenta and membranes is expulsed and ends with the initial physiologic adjustment and stabilization of the birthing parent (a few hours after birth)

• time of maternal physiologic adjustment, transition, and family attachment

  • continued bonding with the newborn

  • mom feels a sense of peace and excitement, is wide awake, and is initially talkative

  • attachment process begins with inspecting the newborn and desiring to cuddle and breastfeed them

• moms body stabilizes after the labor, and after loss of the placenta, amniotic fluid, and membranes.

  • the body returns to a non-pregnant state while adjusting to postpartum changes

• Close monitoring of both mom and the newborn