Process of labor

labor

labor

• is a coordinated sequence of involuntary, intermittent uterine contractions.

• It is the series of events that expels the fetus and placenta out of the mother's body.

• This is made possible by the presence of uterine contractions and abdominal pressure that push the fetus out during the expulsion period of delivery.

• estrogen theory

• progesterone withdrawal theory

• prostaglandins theory

• oxytocin theory

• fetal cortisol theory

Hormonal factors (EPPOF)

estrogen theory

During pregnancy, most of the estrogens are present in a binding form. During the last trimester, more free estrogen appears increasing the excitability of the myometrium and prostaglandins synthesis

prostaglandin theory

• In the latter part of pregnancy, fetal membranes and uterine decidua increase prostaglandin levels.

• This hormone is secreted from the lower area of the fetal membrane (forebag)

• A decrease in progesterone amount also elevates the prostaglandin level.

• Synthesis of prostaglandin, in return, cause uterine contraction thus labor is initiated

progesterone withdrawal theory

• As pregnancy advances, changes in the relative effects estrogen and progesterone encourage the onset of labor.

• A marked increase in estrogen level is noted in relation to progesterone, making the latter hormone less effective in controlling rhythmic uterine contractions.

• Also, in later pregnancy, rising fetal cortisol levels inhibit progesterone production from the placenta. Reduce progesterone formation initiates labor

progesterone

the hormone designed to promote pregnancy. It is believed that presence of this hormone inhibits uterine motility.

oxytocin theory

Pressure on the cervix stimulates the hypophysis to release oxytocin from the maternal posterior pituitary gland as pregnancy advances, the uterus becomes more sensitive to oxytocin. Presence of this hormone causes the Initiation of contraction of the smooth muscles of the body (uterus is composed of smooth muscles).

fetal cortisol theory

Increased cortisol production from the fetal adrenal gland before labor may influence its onset by increasing estrogen production from the placenta

• Uterine distension theory

• Stretch of the lower uterine segment

mechanical factors

uterine distention theory

Like any hollow organ in the body, when the uterus in distended to a certain limit, it starts to contract to evacuate its contents. This explains the preterm labor in case of multiple pregnancy and polyhydramnios.

stretch of the lower uterine segment

• The idea is based on the concept that any hollow body organ when stretched to its capacity will inevitably contract to expel its contents.

• The uterus, which is a hollow muscular organ, becomes stretched due to the growing fetal structures. In return, the pressure increases causing physiologic changes (uterine contractions) that initiate labor.

• Theory of Aging Placenta

• Bradley Theory

• Lamaze

• Alexander Technique

• HypnoBirthing

other theories of labor (TBLAH)

theory of aging placenta

• Advance placental age decreases blood supply to the uterus.

• This event triggers uterine contractions, thereby, starting the labor.

bradley theory

focuses on the natural aspect of birth. This theory of labor asks you to start preparing for your labor during your pregnancy through good nutrition, prenatal exercises and practicing various relaxation techniques. This theory of childbirth focuses on the role of your coach to support and serve as your advocate during your pregnancy and labor.

lamaze

• focuses on providing you with essential information and techniques to help make your birthing experience the one that you truly wanted.

• Pain management techniques such as controlled breathing, massage and changing positions. Although this labor encourages the mother to avoid unnecessary medical interventions such as continuous electronic fetal monitoring, it emphasizes the fact that the regarding Interventions such as pain medication.

alexander technique

• educates about the effect of posture has on the laboring body.

• Through organized lessons that teaches various positions to improve posture and relieve pain during both pregnancy and childbirth, this theory of labor in pregnancy relies primarily on natural methods to help the birthing experience.

• This theory of labor encourages to keep the body relaxed, which may facilitate a quicker, less painful birth.

hypnobirthing

• A theory of labor operating on the belief that the laboring pain will be greatly reduced if the mother will not experience fear or tension.

• uses self-hypnosis to improve the birthing experience.

• The patient will learn breathing and relaxation techniques that will allow the mother to be a calm but active participant in the delivery.

• Similar to Lamaze, this theory of labor focuses on teaching techniques that the mother can use with or without medical interventions such as epidurals.

Power, Passage, Passenger, Presenting part, Psyche

5Ps of Labor

uterine contractions

During the first stage of labor these are the primary force that moves the fetus through the maternal pelvis

Maternal Pushing efforts

During the second stage of labor uterine contractions continue to propel the fetus through the pelvis. In addition, the woman feels an urge to push and bear down as the fetus distends her vagina and puts pressure on her rectum.

1. increment

2. acme

3. decrement

3 phases of contraction

increment

building up of the contraction (longest phase)

acme

peak of the contraction

Decrement

letting up of the contraction

frequency, duration, intensity

are used to describe uterine contractions during labor.

frequency

refers to the time between the beginning of one contraction and the beginning of the next contraction.

duration

is measured from the beginning of one contraction to the completion of that same contraction

intensity

refers to the strength of the contraction during acme

true pelvis

• which forms the bony canal through which the fetus must pass

• 3 sections: inlet, pelvic cavity (midpelvis), and outlet.

sutures

The fetal skull is made up by a number of bones divided by _____

moulding

allows the pelvis to accommodate the fetal head

Caput succedaneum

is the medical term for an area of localized swelling or edema present on the head of a newborn baby following vaginal delivery.

vertex presentation

- Most common type

- Head is flexed.

- Occiput

- Subocipitobregmatic

military presentation

- Head is neither flexed nor extended.

- Occipitofrontal

brow presentation

- Fetal head partially extended.

- Largest anteroposterior diameter

- Sinciput

1. 97%

2. 3%

percent:

1. cephalic presentation

2. breech presentation

breech presentation

- Attitude of the fetus’s hips and knees

- Note Sacrum landmark

complete breech

- Fetal knees and hips are flexed

- Thighs on abdomen

- Calves on posterior of thighs

- buttocks and feet

frank breech

- Fetal hips flexed.

- Knees extended.

- buttocks

footling breech

- fetal hips and legs extended

- single/ double

- feet of the fetus

psyche

is a crucial part of childbirth. Marked anxiety and fear decrease a woman’s ability to cope with pain in labor.

2-4 weeks

baby drops lower into mom’s pelvis _______ before delivery

first stage of labor

onset of contractions to full dilation & effacement of the cervix stage of effacement & dilation.

fetal trashing

hyperactivity of fetus due to lack of Oxygen

second stage of labor (fetal stage)

• Complete dilatation and effacement to birth

• Crowning occurs

BULGING OF PERENIUM

surest sign of delivery initiation

third stage of labor (placental stage)

• 3 – 10 minutes after child birth

• 1 st sign: Fundus rises – CALKIN’S SIGN

brant-andrew’s maneuver

• Slowly pulling the cord and wind at the clamp

• Rapidly – may cause uterine inversion

• involves placing a clamp on the umbilical cord close to the vulva - a technique for expelling the placenta from the uterus

fourth stage of labor (recovery stage)

• First 1 – 2 hours after delivery of placenta

• Maternal observation – body system stabilize

• 1 st hour – q15 min

• 2 nd hour – q30 min

• Placement of Fundus

  • In between umbilicus and pubis symphysis

  • Check bladder, assist in voiding, may lead to uterine atony (internal hemorrhage can occur)

1. gynecoid

2. android

3. anthropoid

4. platypelloid

caldwell-moloy classification of pelvis

gynecoid

• inlet round with all inlet diameters adequate

• midpelvis diameters adeqaute with parallel side walls

• outlet adequate

• favorable for vaginal birth

android

• inlet heart-shaped, with short posterior sagittal diameter

• midpelvis diameters reduced

• outlet capacity reduced

• not favorable for vaginal birth

• descent into lower pelvis

anthropoid

• inlet oval in shape, with long anteroposterior diameter

• midpelvis diameters adequate

• outlet adequate

• favorable for vaginal birth

platypelloid

• inlet oval in shape, with long transverse diameters

• midpelvis diameters reduced

• outlet capacity reduced

• not favorable for vaginal birth

engagement

occurs when the largest diameter of the presenting part reaches or passes through the pelvic inlet

station

• refers to the relationship of the presenting part to an imaginary line drawn between the ischial spine of the maternal pelvis

position

• relationships between the designated landmark on the presenting fetal part and the front sides, or back of the maternal pelvis

• occiput anterior as its most common

• lochia

  • rubra

  • serosa

  • alba

• red, moderate, may have small clots, however large dots not normal

  • dark red colored, bloody up to 1-4 days

  • pinkish and pale brown, 5 to 9 days

  • yellow to white colored, 10 to 28 days (1-2 weeks)

Timing of contractions regular

Radiating contraction pain

Unable to relieve contraction pain with activity

Exam changes present

TRUE labor meaning

Fails to cause change to cervix and baby’s position

Activity diminishes contractions

Keeping feeling contractions above belly button

Erratic timing of contractions

FAKE labor meaning

pre-labor

known as braxton hicks, these late pregnancy contractions thin your cervix and gets it ready for labor

first stage of labor

the cervix thins your cervix util it reaches 10 cm

• 0-4 cm early labor

• 5-8 cm active labor

• 8-10 cm transition

second stage of labor

known as the pushing phase

third stage of labor

after the baby is born, you continue to have contractions so that the placenta may be born

fourth stage of labor

• 2 hours after birth when breastfeeding can be established

• contractions continue so the uterus will shrink

latent/prodromal phase

dilations 0-3 cm

frequency 5-10 mins

duration 20-40 mins

intensity mild

mother is excited, apprehensive but can communicate

active/accelerated phase

• dilations 4-8 cm

• frequency q3-5 mins for 30-60 secs

• duration 30-60 secs

• intensity moderate

transitional/ transient phase

• dilations 8-10 cm

• frequency q 3-5 mins contraction

• duration 45-90 sec

• intensity strong

• mood of mother suddenly change accompanied by hyperesthesia of the skin

engagement

descent

flexion

internal rotation

extension

restitution and external rotation

cardinal movements of mechanism of labor (EDFIERE)

descent

depends on amniotic fluid pressure, direct contracting fundus pressure, force of contractions of diaphragm and extension/straightening of fetal body

flexion

when the head meets resistance from cervix or pelvic floor, it reflexes so the chin can be brought closer to the fetal chest

internal rotation

the outlet is widest in the anteroposterior position therefore the fetus must rotate from the occipitotransverse position

extension

when the head reaches the perineum, the head emerges by __ starting with the occiput then the face and chin

restitution and external rotation

after the head is born, it turns briefly to the position it occupied. the head then turns more to align with the shoulders

expulsion

after birth of the shoulders, the baby is lifted up towards the pelvic bone and trunk by flexing laterally. this completes the 2nd stage

modified ritgen’s maneuver

• done by supporting the perenium with a towel during delivery

• facilitates complete flexion

• avoids laceration

• extracting the fetal head, using one hand to pull the fetal chin from between the maternal anus and the coccyx, and the outer on the fetal occiput to control speed of delivery

pinard maneuver

to facilitate delivery of the legs in a frank breech presentation

lovset’s maneuver

rotation of the trunk of the fetus during a breech birth to facilitate delivery of the armms and the shoulders

mcroberts maneuver

• commonly the first maneuver performed along with suprapubic pressure

• will straighten the maternal sacrum on the lumbar spine

zavanelli maneuver

involves pushing back the delivered fetal head into the birth canal in anticipation of performing a cesarean section in cases of shoulder dystocia

cleidotomy

procedure in which one or both clavicles are cut to reduce the biacromial diameters in cases of a shoulder dystocia not resolved by other maneuvers

crede maneuver (fundal pressure)

involves placing a hand on the abdominal wall near the uterine fundus between the thumb and fingers to help placental separation and delivery