preterm delivery Flashcards
when is a birth PRETERM
before 37 weeks
when is a birth VERY PRETERM
before 32 wwks
when is a birth EXTREMLEY
before 28 weeks
risk factors groups for preterm birth
Previous preterm delivery
Second-trimester abortions
Uterine causes
Abnormal placentation
Infectious causes
Fetal causes
what increases the likely hood of a previous preterm delivery
Low socioeconomic status
Maternal age
before 18
after 40
examples of UTERINE causes for preterm birth
Myoma:
submucosal or subplacental
Uterine septum
Bicornuate uterus
what is a Uterine septum
congenital malformation where the uterine cavity is partitioned by a longitudinal septum; the outside of the uterus has a normal typical shape.
what is a Bicornuate uterus
is an abnormality of the uterus that has two horns and a heart shape.
Abnormal placentation caussing preterm birth
Placenta previa:
Ablatio/Abruptio placentae
what is placenta previa
abnormal position of the placenta causing it to cover the internal os of the cervix
1st degree: abnormal position but doesnt cover os
2nd: low position but does/t cover os
3rd: covers os but not during dilation
4th: completley covered os during dilation
what is abruptio placentae
premature separation of the placenta from the uterus. causing internal or external bleeding
RF: db, HTN, cocaine, trauma, smoking, previous abruption, multiparity
causes painful bleeding
can lead to DIC from hemmorhage
infections causing preterm delivery
Cervical/vaginal colonization
Acute pyelonephritis
Chorioamnionitis
Bacterial vaginosis
what is chorioamnionitis
nfection that occurs before or during labor. The name refers to the membranes surrounding the fetus: the “chorion” (outer membrane) and the “amnion” (fluid-filled sac).
fetal causes of preterm delivery
Intrauterine fetal death
Intrauterine growth retardation
Congenital anomalies
what are the three stages of premature birth
Partus praematurus imminens
Partus praematurus incipiens
Partus praematurus progrediens
what happens in IMMINENS
a. Unregular uterine contractions
b. Cervical canal is closed
c. Tocolitic therapy, Corticosteroids therapy, Antibiotic therapy
what happens in INCIPIENS
a. Regular uterine contractions
b. Cervical change (cervical effacement of 80% or cervical dilatation)
c. Tocolitic therapy, Corticosteroids therapy, Antibiotic therapy
what happens in PROGREDIENS
a. Regular uterine contractions
b. Cervical change (cervical effacement of 80% or cervical dilatation of 2cm or more)
c. PROM = premature rupture of membrane
d. Corticosteroids therapy, Antibiotic therapy
management/dg of imminens and incipiens stages
Non stress test to evaluate uterine activity and fetal heart rate
Assess cervical status, progress of labour and presenting part.
Vaginal swab for bacteria vaginosis and B streptococcus and give antibiotic
what is a non stress test
attaching one belt to the mother’s abdomen to measure
fetal heart rate, and another belt to measure contractions
rx of preterm birth
tocolytic therapy
CorticoSteroid therapy
which drugs are used in tocolytic therapy
magnesium sulfate: antagonises intracellular calcium, increases contraction
Terbutaline: beta 2 receptor, increase sympathetic action, decreaed intracellular calcium ions
Nifedipine: calcium channel blocker
which drug is first choice for tocolytic therapy
magnesium sulfate
which corticosteroids are used in preterm birth
Dexamethasone and betamethasone
purpose of CS therapy
Stimulate pneumocyte 2 cell to produce surfactant
- 28 and 34 weeks of gestation.
