Labor Onset Theories and Signs

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What triggers the release of oxytocin during labor onset?

Decrease in uterine muscle stretching

Increase in progesterone

Low fetal cortisol levels

Pressure on the cervix (correct)

Which factor influences labor onset by changing the hormone balance in the body?

Constant levels of estrogen

Rising fetal cortisol levels (correct)

Increased levels of progesterone

Decreasing placental age

What is an indicator that labor is approaching in a pregnant woman?

Increased abdominal pressure

Frequent urination

Softeness of the cervix (correct)

Dizziness during standing

What is lightening in the context of labor signs?

Descent of the fetal presenting part into the pelvis Signup and view all the answers

Which sign of labor occurs when a woman feels energetic just before labor begins?

Increased level of activity Signup and view all the answers

Which characteristic best describes the contractions of true labor?

Begin irregularly but become regular and predictable Signup and view all the answers

What causes Braxton Hicks contractions to become stronger just before labor?

Hormonal changes in the body Signup and view all the answers

What is referred to as the 'bloody show' during labor?

The expulsion of the mucus plug combined with blood Signup and view all the answers

What risk is associated with the rupture of membranes during labor?

Intrauterine infection Signup and view all the answers

What is the role of prostaglandins in labor onset?

They initiate contractions in conjunction with oxytocin Signup and view all the answers

What is most commonly true about false labor contractions?

They usually disappear with physical activity. Signup and view all the answers

When does lightening typically occur for primiparas?

Approximately 10 to 14 days before labor Signup and view all the answers

At what point is labor typically induced after the rupture of membranes if it does not start spontaneously?

Within 24 hours Signup and view all the answers

Which of the following best describes a physiological change associated with labor onset?

Increased release of epinephrine Signup and view all the answers

What is the significance of Goodell’s sign in pregnancy?

Indicates cervical ripening Signup and view all the answers

Where are true labor contractions typically felt first?

In the lower back Signup and view all the answers

Study Notes

Theories of Labor Onset

Labor is influenced by a combination of factors from the mother and fetus
Factors include:
- Uterine muscle stretching, releasing prostaglandins
- Pressure on the cervix, stimulating oxytocin release from the posterior pituitary
- Oxytocin stimulation working with prostaglandins to initiate contractions
- Change in the ratio of estrogen to progesterone (increased estrogen stimulates contractions)
- Placental age triggering contractions at a set point
- Rising fetal cortisol levels reducing progesterone and increasing prostaglandin formation
- Fetal membrane production of prostaglandins stimulating contractions

Signs of Labor

Preliminary signs of labor should be taught to all pregnant women
Lightening: Descent of the presenting fetal part into the pelvis, typically 10-14 days before labor in first-time mothers
- Associated with shooting leg pain, increased vaginal discharge, urinary frequency due to pressure on the bladder, relief from pressure on the diaphragm and shortness of breath.
- In later pregnancies, lightening may occur on the day of labor or after it has begun.
Increased activity level: Increased energy levels in the morning of labor, related to an increase in epinephrine (due to a decrease in progesterone). Epinephrine prepares the body for labor.
Braxton Hicks contractions: Strong contractions felt towards the end of pregnancy; can be mistaken for true labor

Ripening of the Cervix

Ripening of the cervix, a sign only observable through a pelvic exam, is an integral factor
During pregnancy, the cervix feels softer than usual, similar to an earlobe's consistency (Goodell's sign)
At term, the cervix is very soft, described as "butter-soft"

Signs of True Labor

Uterine Contractions: The surest sign that labor has begun
- Productive uterine contractions (involuntary, intensity can be painful in early labor)
- Breathing exercises can help control discomfort
Show: Cervix softens and ripens, the mucus plug that filled the canal during pregnancy is expelled; blood mixed with mucus produces a pink tinge (bloody show)
Rupture of membranes: Labor can begin with the rupture of the membranes; can be a sudden gush or a slow seeping of clear fluid from the vagina;
- Intrauterine infection and umbilical cord prolapse are two risks associated with ruptured membranes
- If labor hasn't started within 24 hours, induction may be necessary.

Differentiation Between True and False Labor Contractions

False Labor Contractions: Irregular, localized to abdomen, can stop with activity or sleep.
True Labor Contractions: Regular, felt in lower back first, become more intense, continue regardless of activity, lead to cervical dilation.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the theories surrounding labor onset, exploring the various physiological factors that influence labor in mothers and fetuses. It also includes essential preliminary signs of labor that all pregnant women should be aware of, such as lightening and its associated symptoms.