Labor

Labor Definitions:
What happens if a fetus is delivered before 24 weeks?

The fetus is not viable before 24 weeks

Labor Definitions:
What is it called if a fetus is delivered between 24-37 weeks?

Premature (Pre-term)

Labor Definitions:
What is it called if a fetus is delivered after 37 weeks?

Full term

Labor Definitions:
What does dilation refer to?

How dilated the cervical os is

Labor Definitions:
What does effacement refer to?

Thickness of the cervix
-Distance from the internal os to the external os

Stages of Labor:
What is stage 1 of labor?

From the onset of labor until the cervix is fully dilated (10 cm)

Stages of Labor:
What is stage 2 of labor?

From the time the cervix is fully dilated until the baby is delivered

Stages of Labor:
What is stage 3 of labor?

From the time the baby is delivered until the time the placenta is delivered

Stages of Labor:
During what stage does cervical effacement and dilation take place?

Stage 1
-Lasts until the cervix is fully dilated

What is the fetal lie?

Description of the long axis of the fetus relative to the mother

What are the two possible positions of a longitudinal fetal lie?

Head presenting
Breech presenting
--Depends which part is facing down

A longitudinal lie can present with either the head or the breech. Which of these should be delivered vaginally?

Only deliver head-first vaginally
--If breech first, the cervix can tighten around the neck

What is a transverse fetal lie?

Fetus is positioned horizontally

What is an oblique fetal lie?

Fetus is positioned diagonally

What is the fetal presentation?

The part of the fetus that is closest to the birth canal

What is the presenting body part in a longitudinal lie?

Either the head or the breech

What is the presenting body part in a transverse lie?

Shoulder

What is cephalic presentation?

This is the 'normal' position
-Head flexed, occipital fontanel presenting

What is breech presentation?

Butt first

What is the fetal attitude?

The posture of the fetus

The fetal attitude is the posture of the fetus. What is normal?

Rolled into a ball
-Fetus bends over -> back is convex
-Legs flexed over abdomen
-Arms crossed over thorax

What is the fetal position?

Where the fetus is in relation to the birth canal

A Freidman curve is used to plot stage 1 of labor
-X axis = time
-Y axis = cervical dilation
What is the latent phase?

Cervix is slowly dilating

The latent phase of stage 1 labor is when the cervix is slowly dilating. How long does this last?

Lasts up to 20 hours
-Until the cervix reaches 3-5cm

Are contractions occurring during the latent phase of stage 1 labor? How dilated is the cervix?

Yes, contractions are occurring
Cervix is < 3-5cm dilated

Once the cervix reaches 3-5cm, the mother is in what point in labor?

Active labor

Once a woman is in active labor, how quickly does the cervix dilate?
-Nullip?
-Multip?

Nullip - 1.2 cm/hr
Multip - 1.5 cm/hr

Active labor begins when the cervix is 3-5 cm dilated. When does it continue until?

Once the cervix is fully dilated, stage 2 labor begins

What is a protraction disorder in labor?

Protraction = the cervix is dilating, but just dilating slowly

What is an arrest disorder in labor?

The cervix is not dilating at all

What are the cardinal fetal movements to get out of the birth canal?
-Wedding analogy

1 - Engage (engagement)
2 - Descent (out of the church)
3 - Flexion (flex the heads to avoid getting hit with rice)
4 - Internal rotation (turn to look at each other)
5 - Extension (look up to see where limo is)
6 - Externally rotate (wave goodbye to ever

How long does stage 2 of labor last?

Very variable
--Up to 3 hours

What defines stage 2 of labor?

From the time the cervix is fully dilated until the baby is delivered

What is stage 3 of labor?

Delivery of the placenta

How long does stage 3 of labor last?

Usually less than 30 minutes

Before the placenta is delivered, there must be signs that it is separated from the uterus. What happens if the placenta is delivered before the it separates?

It pulls the uterus with it
--Prolapsed uterus = EMERGENCY

Labor Dystocia (Problems with Labor):
There can be problems with 3 P's. What are they?

Power
Passenger
Passageway

Labor Dystocia (Problems with Labor):
The first P is Power. What is the problem here?

The uterus is not contracting

Labor Dystocia (Problems with Labor):
How is a problem with Power dealt with?

The uterus is not contracting
--Give Pitocin (synthetic oxytocin)

Labor Dystocia (Problems with Labor):
The second P is Passenger. What is the problem here?

Problem with the position/size/presentation of the fetus

Labor Dystocia (Problems with Labor):
The third P is Passageway. What is the problem here?
-Bone
-Fat

Bone structure of the pelvis or obesity is blocking the birth canal

What are some contraindications to vaginal delivery?
-Abnormal placenta?
-Umbilical cord?
-C-section?
-Herpes?
-Pelvis?

Abnormal placental implantation
Umbilical cord presentation
Previous c-section
Active genital herpes
Pelvic structure won't accommodate fetus

Contraindications to a Vaginal Delivery:
What is an example of an abnormally implanted placenta?

Placenta previa
--Placenta is implanted over the cervical os

Contraindications to a Vaginal Delivery:
Why is a previous c-section a contraindication?

The scar from the c-section is not as strong as the normal uterine tissue
--When the uterus is contracting, it may rupture through the scar

Contraindications to a Vaginal Delivery:
Why is active genital herpes a contraindication?

Herpes can be transmitted to the fetus