# Week 3 OB

```Chapter 15 &amp; 16
Pregnancy, Labor and Delivery
Calculating EDD
 Calculation of estimated or expected date of delivery (EDD/ birth
o (EDB)/confinement ( EDC)
Naeg&euml;le’s rule
 First day of last menstrual period:
o September 12, 2021
 (-) Subtract 3 months: June 12, 2021
 (+) Add 7 days: June 19, 2021
 (+) Add 1 year: June 19, 2022
 Estimated date of delivery: June 19, 2022
- Best EDD dating – ultrasound prior to 20
weeks GA




Obstetric History
Gravidity (G): a pregnant woman
o Primigravida - first pregnancy
o Multigravida- second pregnancy, etc.
Parity (P): number of births (not the number of fetuses, e.g., twins count as 1 ) carried
past 20 weeks of gestation, whether or not the fetus was born alive.
o Primipara: one birth after a pregnancy of at least 20 weeks (“primip”)
o Multipara: two or more pregnancies resulting in viable offspring (“multip”)
o Nullipara: para 0
GT-PAL – Term, Preterm, Abortions, Living
Question: A woman has twins, now 7 years old, (born at 30 wks GA), a daughter, now 5 (born at
39 wks GA); One miscarriage 3 years ago, a first trimester abortion 2 years ago. She is pregnant.
Which portrays an accurate picture of this woman’s G &amp; P?
1. G4P2121
2. G4P1212
3. G5P1123
4. G5P1122
Prenatal Care
 The first prenatal appointment (the most in-depth) should include:
o Screening and assessments:
 Health history and determining due date
 Medications or supplements taken by the patient
 Psychologic response to the pregnancy
 Discuss any religious, cultural or socioeconomic factors that might
influence the woman’s expectations of the childbearing experience.
 Psychologically: How does the woman seem about the pregnancy?
Support systems, any fears or concerns on the part of the client?
 Assessing for risk of genetic traits
o Laboratory tests:
 Blood type
 Testing for HIV, gonorrhea, and chlamydia, etc.
o Patient education includes:
 Health promotion
 Signs and symptoms to report to provider
 Prenatal Care
 For low-risk patients:
o Prenatal care appointments should occur:
 every 4 weeks (month) until week 28.
 every 2 weeks between 28 and 36 weeks’ gestation.
 Weekly after 36 weeks’ gestation till delivery
 Subsequent (follow up) visits should include:
o Physical assessment &amp; History since the last appointment
o Vital signs, BP and weight assessment
o Fetal heart rate assessment
o Fundal height measurement after 16 weeks of gestation
o Pertinent education
Routine Labs &amp; Procedures
Second trimester:
Ultrasound: look at developing organs, and gross malformatilities
Amniocentesis: amnitoci fluid test, test to see genetic issues
Gluscse: to look for potential development of gestational diabetes of the mother
Rh-negative mom: to see if infants is Rh positive
Step B: expose to infant can cause infection in the baby
Give prophylactic antibiotics
Ch. 5: Cord Prolapse and Non-reassuring
Fetal Status- Case of Letitia Richford
 Letitia and her husband, Don, tried to get pregnant for 1 year.
 After becoming pregnant, she experienced a miscarriage at 8 weeks.
 She is Rh negative.
 She is currently pregnant a second time.
Types of Spontaneous Abortion/Miscarriage
- Look to see how dilated the cervix is



Inevitable – Patient experiences vaginal bleeding and cramping; cervix is dilated.
Missed – Pregnancy is no longer viable, but no cervical dilation, cramping, or bleeding is
present.
Septic – Any spontaneous abortion that occurs with intrauterine infection.


Incomplete – Patient has experienced vaginal bleeding, cramping, and cervical dilation
but not all products of conception expelled. Will need a D&amp;C: Dialation and curatiage:
Surgical scraping to remove fetus.
Threatened – Patient experiences vaginal bleeding but cervix is not dilated. Viable.
Rh Factor in Pregnancy
 Letitia is Rh negative.
 She had a miscarriage, but she may have been exposed to Rh-positive blood from the
fetus.
 After her miscarriage, the provider administers Rho (D) immune globulin (RhoGAM) to
prevent her from developing antibodies.
 If she made antibodies, a future pregnancy could be affected.
Rh Factor in Pregnancy
- Rh factor is dominant
- Parent father is +, likely hood of child being Rh +
Blood usually does not mix during pregnancy:
Upon trauma, delivery, risk for blood mixing is high
Once mother (Rh-) blood interacts to (rh+), she can create antibodies that fight off future
fetuses.
Prenatal Care
 In addition to regularly scheduled appointments, patients should be evaluated for the
following:
! Report above signs as they are highly abnormal !
Physical Examination
 Vital signs
o Chest
o Abdomen, including fundal height ( after 16 weeks) if appropriate
o Extremities
 Pelvic examination -Examination of external and internal genitalia
o Pelvic shape: gynecoid, android, anthropoid, platypelloid; pelvic measurements
Ultrasound
 transvaginal – first trimester
 abdominal - once uterus rises out of pelvis ( after 10-12 weeks)
Amniocentesis – 2nd trimester
 Nonstress Test (NST) –
o Reactive v. non reactive
o More frequently in high risk pregnancies
Contraction Stress Test (CST)
 Not used as much, must stimulate contractions
o Look for accelerations and decelerations in relationship to maternal contractions
Fetal Kick Count –
 &gt;10 fetal movements (kicks) in 2 hours

Level I Basic US
o Calculate gestational age (crown –rump length - CRL)
o Detect gestational sac (5 weeks after LMP)
o Identify number of fetuses
o Document fetus alive
o Detect gross fetal structural anomalies
o Determine fetal position
o Locate the placenta
o Estimate amniotic fluid volume
o Evaluate maternal pelvic masses
Level II US:
o
o
o
o
o
o
Evaluates gestational age
Measure fetal growth
Perform specific examinations of the brain, heart, kidney, and cord insertion
Quantify amniotic fluid volume
Determine placental location
Performed after 18 weeks
Prenatal Diagnostic Studies
 Amniotic Fluid
o Amniocentesis – 2nd trimester


Performed to determine genetic disorders, metabolic defects, and fetal
lung maturity
 &lt;20 weeks – full bladder
 &gt;20 weeks – empty bladder
o Lecithin/sphingomyelin(LS) ratio 2:1 @ 36 weeks = fetal lung maturity – 3rd
trimester
o Rupture of Membranes (ROM)
 Fern test - + for amniotic fluid under microscope
 Nitrazine test – tests pH of vaginal DC, AF alkaline (blue color change)
Teaching: instruct the client to report chills, fever, bleeding, leakage of fluid at the
needle insertion site, decreased fetal movement, uterine contractions, or cramping to
HCP.
Definitions
 Genome: a person’s genetic blueprint determines:
o Genotype: the genetic makeup of an organism; genes inherited from parents
o Phenotype: observed outward characteristics
o Karyotype: pictoral representation of chromosomes
 Genes: individual units of heredity of all traits
o Organized into long segments of DNA - occupies a specific location on a
chromosome
o Determination of particular physical and mental characteristics of humans
 A chromosome: long, continuous strand of DNA carrying genetic information
o Numbered (23 pairs) from largest to smallest, 1 to 22, with #23 being the sex
chromosomes designated by X and Y
 Female – 46 XX
 Male – 46 XY
Chromosomal Abnormalities
 Abnormalities of chromosome (number sets)
o Monosomies; trisomies- Cause down syndrome
o Polyploidy-more than two complete sets of chromosomes.
 Abnormalities of chromosome structure (Treaher – Collins, Fragile X)
o Deletions
o Inversions
o Translocations
 Sex chromosome abnormalities
o Turner syndrome (45X)
o Klinefelter syndrome (47XXY)
In most cases of spontaneous abortion, there is some incompatitbiyt of genetic
material.

Uterine Growth During Pregnancy
Fundal Height Measurement
Preparing for Birth
 Childbirth Classes
o Birth Plans
o Pain Management
 Breathing and relaxation techniques
 Pharmacologic v. non – pharmacologic techniques
o Support Person(s)
 Partner, family member, doula
o Feeding Plan for Infant
 Breastfeeding v. bottle feeding
o Contraceptive Plan
NORMAL PREGNANCY, BIRTH AND AFTER DELIVERY CARE
 Discussion Points: Assessment, health teaching, and evidence-based interventions for
women with a low-risk pregnancy…INTRAPARTUM
 Assessment, health teaching, and evidence-based interventions of women in the normal
intrapartum stage of pregnancy.
o Stages of Labor
o Intrapartum Assessment
 Maternal Assessment
 Fetal Heart Monitoring Basics (NICHD Categories)
o Forceps/Vacuum delivery
o Indications for cesarean birth
o Pain Management during labor
o Nursing Management and Care &amp; Documentation
Essential Questions
 How does labor begin? How long does it last? What are some important
milestones/stages and phases?
 How does the body support a woman during labor and birth?
 How is maternal and fetal safety supported during labor and birth?
 How do we, as providers, support and educate women during labor and birth using the
nursing process?
Delivery Venue Options &amp; COVID-19
 Hospitals:
o Most women with birth plans chose to deliver in hospitals throughout pandemic
o Over 98% of deliveries occur in hospitals; Provides access to key personnel,
equipment, pain control options, and emergency services.
 Home births:
o Due to restrictive visiting and support policies, many mothers looked into this
route
o Many choose home births because of negative hospital experiences; Women
may feel more comfortable, empowered, and in control at home.
 Birthing centers:
o Due to restrictive visiting and support policies, many in Suffolk, LI and upstate NY
chose this route. NYSDOH allowed 4 new birth centers to open
o Generally freestanding centers are not located in a hospital; Midwives attend
most births in birthing centers; Cater to women with low-risk pregnancies;
Transfer agreements with local hospitals.
Five Ps of Labor
 Labor consists of five components, referred to as the five Ps.
 Dysfunction in any one of the five components can cause complications that require
intervention.
 The five Ps of labor include:
o Power—refers to uterine contractions and pushing efforts.
o Passageway—refers to the anatomy of the mother’s bony pelvis and soft tissues.
o Passenger—refers to fetal factors.
o Psyche—refers to maternal state of mind.
o Position—refers to maternal position.
Five Ps of Labor: Power
 Primary powers of labor are the involuntary uterine contractions; occur in the upper
two thirds of the uterus and apply pressure to the fetus.
o cervix dilates and effaces, allowing for passage of the fetus.
o Contraction frequency, duration, and intensity affect power.
o Oxytocin can be administered to augment contraction power.
 Secondary powers are the voluntary maternal pushing effort after the cervix is
completely dilated.
o Effective pushing should occur with the contractions and may require coaching
from the nurse.
Five Ps of Labor: Passageway
 Gynecoid pelvis shape provides the most ideal passageway.
Five Ps of Labor: Passageway
 The relationship between the fetal presenting part and the pelvis is assessed by fetal
station.
 A zero station means the presenting part is at the level of the ischial spines.
Five Ps of Labor: Passenger
Important factors related to the fetus and labor are:
 Fetal head size, fetal presentation, fetal attitude, fetal lie, and fetal position.
 The fetal head is the largest part of the fetus.
 The fetal skull bones are not fused and allow for the head to adjust to the birth canal.
 Fetal presentation refers to the part of the fetus entering the pelvis first.
o The majority of babies are in a headfirst or cephalic presentation.
o A breech presentation means the baby is in a buttocks or feet first presentation.
 Fetal attitude refers to the position of the fetal parts in relationship to each other.
o Back of the head is the biggest… usually comes out first
Passenger: Fetal Presentation
 Cephalic (vertex)
o Flexed
o Military
o Brow
o Face


Breech
o Frank
o Full or complete
o Footling or
double
footling
Shoulder
Passenger: Fetal Attitude &amp; Fetal Lie
 Fetal Attitude: Fetal parts in relation
to itself

Fetal Lie: Fetal position in relation to
mother’s
spine
Passenger: Fetal Position
- Right or left of presenting occipital (back of the baddies head)
 Landmarks
o Occipital bone (O): vertex presentation
o Chin (mentum [M]): face presentation
o Buttocks (sacrum [S]): breech presentation
o Scapula (acromion process [A]): shoulder presentation
 Three-letter abbreviation for identification based on:
 On Right or left side of pelvis
 Presenting part (see above)
 In anterior or posterior position (of the presenting part)
Face towards mom’s butt is the best…
Five Ps of Labor: Maternal Psyche &amp;
Position
 A woman’s psyche can impact labor.
Examples of factors that can slow
labor include:
o Anxiety
o Stress
o Fear
o Pain tolerance
 Relaxation can augment labor.
 Contractions are generally more
effective when:
o Woman is in an upright
position.
o Gravity can assist successful
labor and delivery.
o woman’s hips are sharply
flexed, like when squatting.
 Encouraging movement into positions of comfort is associated with improved outcomes.
 Lithotomy position for birth may have evolved for the ease of the provider. Not optimal
for delivery from mother’s point of view
o Straightening and flexing of the pelvis to extend and straighten birth canal.
 Labors is confirmed by dilation and effacement of the cervix.
Signs of Labor
 Mechanisms that initiate labor remain unclear and involve many factors.
 Signs of impending labor include:
o Contractions become regular
o Presence of bloody show
o Descent of the fetus into the birth canal (lightening), may occur about two weeks
before labor for a primigravida
o Nesting impulse
o GI distress (heartburn, nausea, diarrhea)
o Weight loss of 1 to 3 pounds just before onset of labor
 Labor is confirmed by cervical change (dilation and effacement).
Stages and Phases of Labor
 There are four (4) stages of labor.
 First stage: dilation and effacement of the cervix.
o Latent phase: 0–6 cm dilation
o Active phase: 6-8 cm dilation (2014 change)
o Transition phase: 8–10 cm dilation



Second stage: pushing started with the cervix completely dilated and ends with the
birth of the baby.
Third stage: begins with the birth of the baby and ends with delivery of the placenta.
Fourth stage: begins with the delivery of the placenta and ends after 4 hours or when
the mother becomes clinically stable.
Cervical Dilation &amp; Effacement
 Stages and Phases of Labor: First Stage
Latent phase characteristics:
o Longest lasting phase of labor
o Period of excitement
o Contractions feel like menstrual cramps and are mild to palpation
Active phase characteristics:
o Women may become more focused, anxious, or restless.
o Contractions become more regular and painful.
o Contractions are moderately strong to palpation.
Transition phase characteristics:
o Contractions strong and close together
o Women may feel out of control, irritable, or dependent.
o Shortest lasting phase of labor
Second Stage of Labor
 Pushing may be delayed until the woman feels the urge to push.
 Second stage may last 20 minutes to 2 hours.
 As the fetus descends through the birth canal, the fetal head rotates for optimal
delivery. These movements are called cardinal movements.
o Engagement: Fetal head reaches level of the ischial spines.
o Descent: Fetus moves past the ischial spines.
o Flexion: Fetal chin touches chest in response to pressure from maternal tissue.
o Extension: Fetal chin comes off the chest and the neck arches as the head is
born.
o External rotation: Fetal head rotates as the shoulders move into position for
delivery.
o Expulsion: Body of the fetus is born.
Third Stage &amp; Fourth Stages of Labor
 Third stage of labor
 delivery of placenta - complete within 5 to 30 minutes.
 The uterus contracts to deliver the placenta.
o Uterus gets rounder, umbilical cord lengthens, may feel a gush of blood
 After delivery of the placenta, the uterus continues to contract to “pinch” or close the
open blood vessels in the decidua to prevent maternal hemorrhage.
 Failure to contract is called uterine atony and is a primary cause of postpartum
hemorrhage.




Fourth stage of labor
The nurse should administer pain medications as needed.
The nurse should assist the patient with:
o Skin-to-skin contact
o Initiating breastfeeding
o Assessment Times
 Every 15 minutes in 1st hr
 Every 30 minutes in 2nd hour
2 hours after birth the nurse should assess:
o uterine position
o vaginal bleeding (lochia)
o vital signs
```