PB 172: Premature rupture of membranes Flashcards
What percentage of US pregnancies are preterm, PPROM, or PROM?
Preterm: 12%
PPROM: 3%
PROM: 8%
In patients who present with PROM, how soon do they deliver?
With expectant management: 50% within 5h, 95% within 28h
What are the sequelae/adverse effects in patients with PPROM?
50% give birth w/in 1 week (previable PPROM - 40-50% w/in 1 wk, 70-80% w/in 2-5w)
15-25% intraamniotic infection
15-20% postpartum infection (higher in earlier GA)
2-5% abruptio placentae
1-2% risk of antenatal fetal demise
Increased risk for fetus of neurodevelopmental impairment, neonatal white matter damage
At what point are previable PPROM infants more likely to survive?
22w - 57.7% survive vs. 14.4% before that GA; rarely lethal after 23-24w rupture
Worse if before 24w: higher incidence of pulmonary hyperplasia causing lethality - predictors are low AF volume, early GA rupture
How is PROM defined?
Rupture of membranes before onset of labor - d/t normal weakening of membranes and shear forces from contractions
What is PPROM and what risks increase chances of having it?
<37w PROM, commonly associated with INTRAAMNIOTIC INFECTION
Risks higher with previous PPROM, short cervix, bleeding in 2nd/3rd trimester, low BMI, low socioeconomic status, smoking, illicit drug use
What do babies look like after prolonged oligohydramnios?
Retal deformations (Potter-like facies with low-set ears, epicanthal folds), limb contractures, positioning abnormalities → often resolve with growth of baby, PT
How do you diagnose PROM?
History
SSE: (1) visualize fluid, (2) pH 7.1-7.3 (usually vaginal secretions 4.5-6), (3) ferning
Fetal fibronectin: sensitive but nonspecific - negative test suggests intact
Transabdominal indigo carmine dye: last resort if unclear after full eval; dye will pass into the vagina and stain tampon/pad (can also stain maternal urine!)
ACOG recommendations for PROM management at term or late preterm (34w-36w6d)?
Labor induction is preferred!
Meta-analysis of 12 RCTs: IOL reduces rates of chorio, endometritis, NICU admission w/o increasing C/S or operative delivery risk → expectant management is okay but have to watch for infection
Oxytocin and prostaglandins (misoprostol) equally effective, but higher rate of chorio with miso
Not enough evidence to justify prophylactic abx except for GBS
With IOL: need to allow adequate contractions 12-18h to allow latent phase progression before dx of failed induction and moving to C/S
ACOG recommendations for management of preterm PROM (24w-33w6d?)
Keep mom pregnant as long as possible and give antibiotics, corticosteroids (BMZ), and magnesium sulfate
Abx prolong latency, reduce infection, reduce GA-dependent morbidity!
NICHD network trial course (7d total): IV ampicillin (2g q6h) and erythromycin (250mg q6h) x 48h → PO amoxicillin (250mg q8h) and erythromycin base (333mg q8h) x 5d; don’t give Augmentin because it increases risk of necrotizing enterocolitis
Single course of corticosteroids: reduces neonatal mortality, ARDS, intraventricular hemorrhage, necrotizing enterocolitis. Okay as early as 23w0d (if at delivery risk within 7d) up to 34w, single course may ALSO be helpful in late preterm period (34w to 36w6d) where it reduces respiratory morbidity in newborns
Magnesium sulfate for neuroprotection helpful if birth <32w0d in multiple RCTs, reduces risk of cerebral palsy in surviving infants - optimum dose not known
Tocolysis NOT recommended: longer latency period and lower delivery risk in 48h, but higher risk of chorio in pregnancies before 34w
ACOG recommendations for management of previable PPROM (<24w)?
Extensive family counseling about what to expect - expectant management or IOL are ok choices
Abx can be considered as early as 20w0d
Not recommended before viability: GBS prophylaxis, corticosteroids, tocolysis, mag sulfate for neuroprotection
When would you offer cerclage in subsequent pregnancies?
Current singleton pregnancy, prior spontaneous preterm birth <34w, short cervix (<25mm) before 24w
