Transcript PTB.pptx

Preterm Birth
Hazem Al-Mandeel, M.D
Course 481
Obstetrics and Gynecology Rotation
Definition and Incidence
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Preterm birth is the delivery of a fetus after
20 wks of gestation and before term
(completed 37wks)
Preterm Labor is ………………
Preterm birth is a major cause of perinatal
mortality and morbidity
PTB occurs in 10% to 12% of pregnancies
50% to 70% of neonatal mortality and morbidity
is secondary to PTB
Etiology and Risk Factors
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3 etiologic subtypes of PTB:
1. Spontaneous PTB (idiopathic)
2. Preterm premature (prelabor) rupture of
membranes
3. Induction of Labor for medical indications
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Risk Factors:
H/O preterm birth
Multiple gestation
Polyhydramnios
Urinary tract Infection
Abortion (especially 2nd trimester)
Cervical incompetence
Ethnic background
Diagnosis of Preterm Birth
Diagnosis done by clinical assessment
 Initial assessment of women with preterm labor
and intact membrane is by pelvic examination
 Dx of PTB is based on:
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1. Documented uterine contractions
2. Documented cervical dilatation or change
Management of Preterm Labor
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Complete assessment of the patient for
possible corrected underlying cause (e.g. UTI)
Rule out the presence of premature rupture of
membranes
Start I.V hydration and bed rest
Obtain vaginal swab and urine for culture (R/O
vaginal infection or UTI)
Obtain obstetrical ultrasound to assess fetal
presentation, weight, and cervical length
Management of Preterm Labor
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If gestational age is ≥ 34wks  no further action
If gestational age is < 34wks  consider the
following:
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Antenatal corticosteroid (glucocorticoids) to reduce
risk of preterm mortality and morbidity
Uterine tocolytic therapy (to stop or delay delivery)
e.g.: Ritodrine, Nifedipine, NSAID, Oxytocin antagonists
C.I: antepartum bleeding, severe preecalmpsia,
chorioamnionitis, IUGR, IUFD, fetal anomalies
Antibiotic therapy (for Group B streptococcal
prophylaxis)
Labor and Delivery of the Preterm
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The Lower limit of viability of a preterm infant is
24 wks or 500g weight
Vaginal delivery is preferred in vertex presentation
If breech presentation cesarean section is
preferable
Continuous fetal heart monitoring is necessary
Vacuum/ventose assisted delivery should be
avoided
Neonatal intensive care unit is
Prevention
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Identify patients at risk and provide close
follow up
Treatment of bacterial vaginosis
Treatment of asymptomatic bacturia
Measurement of cervical length in high risk
patients
The use of fetal fibronectin test for women
with PTL
Stress reduction and improvement of nutrition