PROM/PPROM Flashcards
PROM vs PPROM definition
Prelabor rupture of membranes= 37 weeks and after
Preterm PROM = less than 37 weeks
Both are BEFORE onset of labor (contractions causing cervical change)
Latency period definition
Time between ROM and onset of labor
Inversely related to gestational age (longer latency with ROM at earlier gestational age)
Risk factors for PPROM/PROM
Prior PPROM Vaginal/sexually transmitted infections Low BMI < 19.8 Low socioeconomic status Smoking Illicit drug use Short cervix Nutritional deficiency Multiple gestation Polyhydramnios Placental abruption
Etiology of PROM/PPROM
Can be a result of normal physiological weakening of the membranes combined with shearing forces created by contractions
Can also be due to premature amniotic collagen/extracellular matrix degradation → increased prostaglandin formation → promotes cervical ripening and contractions (this cascade can be triggered by bacterial endotoxins)
PPROM most likely due to inflammation and infection of the amniotic sac (gonorrhea, chlamydia, bacterial vaginosis, vaginal candidiasis, etc)
How does nitrazine work? And causes of false positive/negative?
pH test; amniotic fluid is alkaline (pH 7.1-7.3)
False positive caused by blood (if >10%), semen, BV, urine, soap
False negative caused by prolonged rupture with not much residual fluid
How does AmniSure and ROM Plus work? And causes of false positives?
AmniSure- binds placental alpha microglobulin-1 (PAMG-1); per manufacturer, false positive with blood (if >50%); use prior to lubricant (digital exam)
ROM Plus- detects insulin growth factor binding protein-1 plus alpha-fetoprotein; per manufacturer, false positive with blood (if >10%); lubrication does not affect results
What is FFN and how reliable is it?
Fetal fibronectin test
Sensitive but nonspecific; negative= strongly suggestive of intact membranes but positive isn’t diagnostic
Management of PPROM/PROM if > 34 weeks?
Deliver!
Penicillin if GBS positive; otherwise no latency antibiotics
Can consider steroids but don’t delay delivery (and no tocolytics)
Management of PPROM/PROM if < 34 weeks but more than viability?
Steroids (2 doses, 24 hours apart)
Latency antibiotics
Magnesium for 12 hours or until delivery (if < 32 weeks and imminent delivery risk)
Why do you give magnesium for < 32 weeks and what is the dose?
Neuroprotection; has been shown to decrease rate of cerebral palsy
dose: IV 4-6g loading –> IV 1-2g maintenance
consider renal function
Magnesium not recommended prior to viability
What’s the dose for steroids and when can you start giving it? Can you give a rescue course if patient has already received it in the past?
Betamethasone: two 12mg doses 24 hrs apart IM
Can also give dexamethasone: four 6mg doses every 12 hrs IM
Typically start at 24 weeks but can consider as early as 23 weeks if likely to deliver within 7 days; not much data on rescue course in PPROM
Sterioids not recommended prior to viability
What is the latency antibiotic regimen?
Per ACOG, IV amp 2g q6h and IV erythromycin 250mg q6h for 48h. Then transition to oral amoxicillin 250mg q8h and oral erythromycin 333mg q8h for 5 days
Instead of doing IV and oral erythromycin, can do single dose of oral azithromycin 1g
What is the upper and lower GA limit of giving tocolytics?
Typically 34 weeks but can be hospital dependent
Can’t give tocolytics prior to viability
When are PPROM/PROM patients likely to deliver?
> 50% give birth in 48 hours; >90% give birth in 1 week
Latency period inversely related to gestational age (longer latency with ROM at earlier gestational age)
How do you diagnose PPROM/PROM and what labs should you do?
Amnisure prior to pelvic exam
Speculum exam: pooling of fluid in vault
Ferning (arborization), nitrazine paper, amnisure, ROM plus
AVOID DIGITAL CERVICAL EXAMS unless imminent delivery
Collect UDS, UA, UCx, GCCT, wet prep, GBS (if not done yet)
