Intrapartum and Labor Theories Quiz

Objectives

• Students will be able to discuss theories of labor onset
• Describe signs and symptoms of labor
• Differentiate between true and false labor
• Contrast advantages and disadvantages of different childbirth settings
• Explain the 5 Ps and how they influence labor and birth
• Differentiate the 4 stages of labor
• Identify nursing actions for each stage
• Identify common discomforts
• List 5 nursing diagnoses for childbearing women

Intrapartum

• Also known as parturition or childbirth
• Begins with contractions and ends 4 hours after delivery
• All products of conception – baby, placenta, fetal membranes – are expelled
• Intrapartum care covers labor and delivery
• Terms like toco- and toko- relate to childbirth
• Eutocia: normal labor
• Dystocia: difficult labor

Labor

• Uterine contractions expel the fetus and products of conception
• Parturient woman: woman in labor
• Puerpera: woman who has given birth

Theories of Labor Onset

• Uterine stretch theory: Hollow muscular organs contract when stretched to capacity.
• Oxytocin theory: Rising oxytocin levels stimulate contractions near term.
• Prostaglandin theory: Fetal membranes produce prostaglandins, hormones that start uterine contractions.
• Progesterone theory: Decreasing progesterone around term allows uterine contractions to occur.
• Aging placenta theory: Aging placenta produces less progesterone, leading to rising prostaglandin and estrogen levels and promoting contractions. Also includes fetal adrenal and pituitary hormones initiation of labor.

Passenger (Fetus)

• Fetal head: Major presenting part; bony and noncompliant.
• Sutures and fontanelles: Spaces between skull bones allow for molding during birth. Important landmarks include the sinciput (brow), vertex (top), and occiput (back of the head). Various diameters (biparietal, bitemporal, bimastoid) are essential to understand fetal head's relationship to pelvic dimensions.
• Fetal lie: Relationship of fetal long axis to mother's long axis. Longitudinal lie (parallel) is most common. Transverse lie (perpendicular) is unusual.
• Fetal attitude: Relationship of fetal parts to each other. Complete flexion is most favorable for vaginal birth.
• Fetal presentation: Part of fetus first entering the pelvis. Cephalic (head first) is desirable; breech or shoulder presentations are less ideal.
• Different types of presentations (Vertex, complete breech, Frank Breech, Footling breech) & their associated attitudes (attitude of flexion, extension...).

Passageway (Pelvis)

• Pelvis is the birth canal, divided into false and true pelvis.
• Important measurements include diagonal conjugate, true conjugate, obstetrical conjugate, and ischial tuberosity diameter.
• Soft tissue structures (cervix, vagina, perineum) must stretch. Progesterone and relaxin impact tissue elasticity.
• Specific pelvic shapes (gynecoid, anthropoid, platypelloid, android) influence vaginal delivery options.

Powers

• Uterine contractions: Primary power driving labor. Phases include increment, acme, and decrement; intensity is measured in millimeters of mercury (mmHg).
• Frequency: Time between the start of one contraction to the start of the next, measured in minutes.
• Duration: Length of a contraction, measured in seconds.
• Intensity: Strength of contractions, measured in mmHg.
• Hydrostatic pressure: Pressure from amniotic fluid aids in cervical dilation.
• Maternal pushing: Important in the second stage of labor.

Psyche/Psychological Response of Mother

• Psychological state, feelings experienced, coping mechanisms play a significant role during labor.

Position of Mother:

• Frequent changes in positions during labor are crucial for comfort and circulation. Upright, lateral, semi-recumbent positions are beneficial
• Positions like sitting, kneeling, squatting, walking, semi-sitting, side-lying offer support and aid in labor.

Fetal Position

• Relationship of the fetus' presenting part (e.g., occiput, sacrum) to the maternal pelvis, categorized by its relationship to the left, right, anterior, and posterior sides. e.g. Left occipital anterior (LOA)

Station

• Level of fetal presenting part relative to the ischial spine, an anatomical landmark in the mother's pelvis.

False and True Labor

• False labor (Braxton Hicks) contractions aren't progressive, aren't regular in intensity, frequency, or duration, and often diminish with activity or rest.
• True labor contractions are progressive in intensity, frequency, and duration. They are regular, typically intensify with activity, and cause cervical dilation and effacement.