Name the Five Factors that affect Labor; 

The 5 P's

 Beginning of Chapt. 9

1. Passenger (Fetus & Placenta)
2. Passageway (Birth Canal) {Fetal head, Attitude, Lie, Presentation, Position of fetus}
3. Powers (Contractions)
4. Position of mother
5. Psychologic response of Mother

The fetal Head

2 Parietal Bones

2 Temporal Bones

1 Occipital Bone

1 Frontal Bone

 Membranous Sutures

1. Sagittal
2. Lambdoidal
3. Coronal
4. Frontal 

 What are Fontanels?

Where are they located?

 Membrane-filled spaces

Located where the sutures intersect

During labor, after ROM's,

 palpation of fontanels and sutures during vaginal examination reveals what about the fetus?

• Fetal Presentation
• Fetal Position
• Fetal Attitude 

1. The Anterior fontanel
2. The Posterior fontanel
    

Describe the shape of the anterior &

posterior fontanels

1. Anterior Fontanel- Larger of these; Diamond shaped approx. 3cm by 2cm
2. Posterior Fontanel- Triangular approx. 1cm by 2cm

1.  Anterior- Lies at the junction of the sagittal, coronal, and frontal sutures (soft spot; top of head).
2. Posterior- Lies at the junction of the sutures of the two parietal bones & the occipital bone (back of head). 

Anterior fontanel closes by 18 months

Posterior fontanel closes 6-8 weeks

after birth

Sutures & Fontanels 

• What is molding?
• How does it accomodate the fetal skull during labor?
• When does the newborn assume their normal shape of the head

1. Molding is the slight overlapping of the bones that occurs during labor
2. The capacity of the bones to slide over one another permits adaptation to the various diameters of the maternal pelvis
3. Within 3 days after birth 

Part of the fetus that enters

 the pelvic inlet first

 What are the three main presentations?

1. Cephalic presentation (Occiput--Head first)
2. Breech presentation (Sacrum--buttocks or feet first)
3. Shoulder presentation (Scapula--Shoulder first; transverse lie- C/S required

C/S= Cesarean Section

 Part of the fetal body first felt by the

examiner (Dr. or RN), during a vaginal exam

Vertex

1. Fetal Lie
2. Fetal Attitude
3. Extension or Flexion of the fetal head 

1. What are the two primary lies?
2. Where is the long axis of the fetus positioned r/t the mothers long axis?

1. Longitudinal or Vertical--Fetus' long axis is parallel with the long axis of the mother 
2. Transverse, Horizontal, or Oblique---Fetus'long axis is at a right angle diagonal to the long axis of the mother

1. Longitudinal lies are what two types of presentations?
2. What type of delivery does a transverse lie require?

1. Cephalic or Breech presentations
2. C/S b/c vaginal birth cannot occur when the fetus stays in a transverse lie.  Oblique lie, is uncommon and fetus usually coverts to the longitudinal or transverse lie during labor. 

The relationship of the fetal body parts to each other/or relationship of the presenting part

What is the following attitude known as:

The back of the fetus is rounded so that the chin is flexed on the chest, the thighs are flexed on the abdomen, and the legs are flexed at the knees.  The arms are crossed over the thorax, and the umbilical cord lies between the arms and the legs.

What is approx. 9.25 cm at term,

Is the largest transverse diameter, and

Is an important indicator of fetal head size called?

Biparietal Diameter

In a well-flexed cephalic presentation, the biparietal diameter will be the widest part of the head entering the pelvic inlet.

• Position is denoted by a three-letter abbreviation.  (ie. ROA, LOA,RSA, ect)

• Explain what each letter stands for 

First Letter = Location of the presenting part in the right (R) or left (L) side of the mothers' pelvis.

The middle letter = The specific presentation part of the fetus----Point of reference (O for occiput, S for sacrum, M for mentum (chin), and Sc for scapula (shoulder).

The 3rd letter = Location of the presenting part in relation to the anterior (A), posterior (P), or transverse (T) portion of the maternal pelvis.

If the occiput is the presenting part and is located in the right anterior quadrant of the maternal pelvis....then list the abbreviation

If the sacrum is the presenting part and is located in the left posterior quadrant of the maternal pelvis....then list its abbreviation

--The relationship of the presenting part of the fetus to an imaginmary line drawn between the maternal ischial spines

--Is a measure of the degree of descent of the presenting part of the fetus through the birth canal....Is known as?

Station

The placement of the presenting part is measured in cm above or below the ischial spines.

(ie. When the lowermost portion of the presenting part is 1cm above the  the spines = station is -1.  At the level of the spines =  station is 0.  When the presenting part is 1cm below the spines = station is +1.

Birth is imminent when at +4 or +5cm

Station should be determined when labor begins so you can measure fetus' rate of descent during labor.

What term indicates that the largest transverse diameter of the presenting part of the fetus has passed through the maternal pelvic inlet into the true pelvis and corresponds to station zero (0)

The passageway/ or birth canal is composed of what?

---The mothers rigid bony pelvis

The soft tissues of the:

            Cervix

            Pelvic floor muscles

            Vagina

            Inroitus (external opening to the vagina)

If babies presenting part is +3 what is occuring?

The infant's presenting part is crowning and delivery is imminent

If the soft tissues contribute to vaginal birth of the fetus, espescially the musclualr layers of the pelvic floor, then what is the maternal pelvis' role?

Maternal pelvis plays a far greater role in the labor process b/c the fetus must successfully accommodate itself to this rigid passageway.  Thus, the size and shape of the pelvis need to be determined befor labor begins

What is the bony pelvis separated by?

What two parts is the pelvis divided into

• Brim or inlet

1. True pelvis- Involved in birth, divided into 3 planes (the inlet or brim; the midpelvis, or cavity; and the outlet)
2. False pelvis- Part above the brim; plays no part in childbearing.

Because the fetus must first pass beneath the pubic arch, a narrow subpubic angle will be less accommodating than a rounded wide arch.

Gynecoid---50% of all women

Brim = slightly ovoid or transversely rounded

Shape =  Round

Depth = Moderate

Ischial Spines = Blunt, somewhat widely separated

Scrum = Deep, curved

Subpubic arch = Wide

Usual mode of birth = Vaginal, Sponatneous, Occipitoanterior position

The contractions  of the uterine body exert downward pressure on the fetus, pushing it against the cervix.  What does this cause the cervix to do?

The cervix effaces (thins), and dilates (opens) sufficiently to allow the first fetal portion to descend into the vagina. 

Involuntary contractions

Primay powers are responsible for:

          -Effacement of cervix= shortening/ thinning normally 2-3cm long and 1cm thick

          -Dilation of cervix= widening of the cervical opening

* When cervix is fully dilated it can no longer be palpated

* Full dilation marks the end of the first stage of labor

--The urge to bear down

--Have no effect on cervical dilation

--Valsalva Maneuver is discouraged b/c it cuts off oxygen to the baby.

What are the benefits of frequent position changes during labor for woman

--Relieves fatigue

--Increase comfort

--Improve circulation

Lightening-Dropping

Low back pain

Bloody show

Weight loss of 0.5-1.5kg

Surge of energy= Nesting