Chapter 42: Preterm Birth Flashcards
Define: A. SGA B. LGA C. Low birthweight D. Very low birthweight E. Extremely low birthweighr
SGA <10th percentile LGA >90th percentile LBW 1500-2500g VLBW 1000-1500g ELBW 500-1000g
Define: A. Early preterm B. Late preterm C. Early term D. Term
Early PT <33 6/7 wks
Late PT 34-36 wks
Early term 37-38 6/7 wks
Term 39-40 6/7wks
True or False.
Newborns born before 37 weeks suffer various morbidities, largely due to organ system immaturity.
True
After achieving a birtheeighht of _______ grams or a gestational age of ____ weeks for females or ____ weeks for males, survival rates reach 95%.
After achieving a birtheeighht of >= 1000 grams or a gestational age of 28 weeks for females or 30 weeks for males, survival rates reach 95%.
This term is defined as the lower limit of fetal maturation compatible with extrauterine survival.
Threshold of viability.
Active brain development occurs in what trimester?
2nd and 3rd
Enumerate morbidities of newborns born during the periviable period (20-26 weeks AOG).
Hypoxic-ischemic injury and sepsis Intellectual disability Cerebral palsy Blindness Seizure Spastic quadriparesis
True or false.
Retinopathy of prematurity is a long-term ophthalmologic problem among very low birthweight infants.
False. It is a short term problem.
Long term problems include: blindness, retinal detachment, myopia and strabismus.
True or false.
Delivery before 23 weeks typically results in death, and survival rates approximate only 10%.
False.
Delivery before 23 weeks typically results in death, and survival rates approximate only 10%.
Additional info:
For those who live, morbidity is universal.
Those born <25weeks are believed to be specially susceptible to brain injury
Enumeration.
The obstetric care consensus document addresses management ootions based on the clinical caharacteritics of a given pregnancy. Enumerate monmodifiable and potentially modifiable factors.
Nonmodifiable factors:
Fetal gender
Fetal weight
Plurality
Potentially modifiable factors: Location of delivery Intent to intervene by CS or induction Corticosteroids Magnesium sulfate
According to the Obsteteic Care Consensus, when should CS delivery be considered for fetuses at:
A. 23-24 weeks?
B. Below 20 weeks?
Consider CS at:
23-24wks for fetal indications
Below 22 weeks for maternal indications.
Additional Info:
In Parkland Hospital, CS delivery for fetal indications are practiced in women at 25 weeks and beyond.
At 24 weeks, CS delivery is not offered unless EFW is at 750g or greater.
Distribution of preterm births by gestational age.
34-36wks: 71.3%
32-33wks: 12.1%
28-31wks: 9.5%
27wks and below: 7.1%
80% of late preterm births are due to:
A. Spontaneous labor and PPROM B. Hypertension C. Abruptio placenta D. Placenta previa E. Fetal complications
A.
Soontaneous labor 45% PPROM 35% Hypertension 13% Fetal complications 2% Abruptio 1% Previa 1% Others 3%
Enumerate:
4 direct causes of preterm births.
Preterm labor with intact BOW (40-45%)
PPROM (30-35%)
Maternofetal indications (30-35%)
Twins and higher-order multifetal births
All of the following are major causes of spontaneous preterm labor, EXCEPT:
A. Maternal-fetal stress B. Multifetal gestation C. Premature cervical changes D. Infection E. Uterine distention
B. Multifetal gestations
4 Major Causes of spontaneous preterm labor: Uterine distention Maternal-fetal stress Premature cervical changes infection