Preterm labor and PPROM Flashcards
Spontaneous preterm birth is a direct result of:
Preterm labor (myometrium), PPROM (membranes) and Cervical Insufficiency (Cervix)
Preterm delivery affects how many pregnancies in the US per year?
1/10 per year
What percent of preterm birth occurs in women without any risk factors?
50%
What are the 3 main risk factors for spontaneous preterm birth?
Multiple fetal gestation, history of prior PTD , history of bleeding in pregnancy
What is the definition of preterm labor?
Persistent uterine contractions that cause the cervix to dilate to 2 cm and efface to 80%
What percentage of patients diagnosed with PTL will deliver at term?
50%
True or false: Activity restriction increases the risk for preterm delivery?
True
What cervical length is reassuring that the likelihood of PTL is low?
CL > 3.0 CM
What cervical length is worrisome for increased likelihood of PTL?
CL < 2.0 CM
When should you send an FFN in the work up for PTL?
When the cervical length is between 2.0 - 3.0
How long is an FFN predictive of PTB
Predictive for the next 14 days
FFN has a _____ negative predictive value and a _____positive predictive value
High, Low
How long do tocolytics usually delay delivery?
Up to 48 hrs
True or false: Tocolytics improve the survival and mortality associated with
False
When should Tocolysis be used and for how long?
Used to get through steroid window for up to 48 hrs
When you use Magnesium with Nifedipine what complication should you be aware of?
hypocalcemia
Should magnesium sulfate be used as a tocolytic?
No
What is the best tocolytic agent to use prior to 32 wga?
Indomethacin
What is the dosing of Indomethacin that you should use?
50 mg PO loading dose, followed by 25 - 50 mg q 6 hrs for 48 hrs
What are the contraindications to using Indomethacin?
Oligohydramnios OR > 32 wga
What is the best tocolytic age to use after 32 wga - 34wga ?
Nifedipine
What is the dosing for Nifedipine that you use for tocolysis
10 - 20 mg PO q 3-6 hrs until rare UC, THEN 30 - 60 mg XR q 8 hrs for 48 hrs
What are contraindications to tocolysis?
Chorioamnionitis, fetal compromise, abruption, lethal anomaly, IUFD, severe PreE, Maternal shock
What are the fetal benefits of preterm steroid administration?
Reduced RDS, IVH, CP
Steroids accelerate maturation in all fetal tissues by _____.
1 week
What are the two dosing regimens for preterm steroids?
Betamethasone 12.5 mg q 24 hrs 2 doses, Dexamethasone 6 mg q 12 hrs 4 doses
When should you offer a repeat course of steroids?
If greater than 7 days since first administration and gestational age < 34 wga
What gestational age is it appropriate to offer preterm steroids?
24w0d –> 33w6d if delivery is likely in the next 7 days
At what gestational age are late preterm steroids offered?
34w0d - 36w6d
What fetal risks are decreased by late preterm steroids?
decreased need for respiratory support, TTM, decreased in prolonged NICU stay > 3 days
When should you NOT administer late preterm steroids?
Chorioamnionitis, If previously received antenatal steroids
What are the risks of late preterm steroids?
Increased risk of neonatal hypoglycemia
up to what gestational age should magnesium sulfate be administered?
up to 32 wga
What specific outcome does administration of mag sulfate for PTL < 32wga improve and by how much?
Decreases risk of moderate to severe CP by half
What is the dosing for Mag Sulfate for neuroprotection in preterm labor?
6g load followed by 2g/hr for 12 hrs
What should you do with mag sulfate if a PTL patient is not delivered within 12 hrs?
Stop magnesium and restart for delivery or if labor progresses.
When is it necessary to rebolus the magnesium following discontinuation for preterm labor
If greater than 6 hrs from discontinuation
How long are GBS cultures valid for?
5 weeks
Should you start GBS prophylaxis for preterm labor if status is unknown?
Yes
When should you stop GBS prophylaxis for preterm labor?
If patient not in true labor or GBS swab returns negative
What is the most sensitive test for PROM?
nitrizine
What is the most specific test for PROM?
Ferning
Amniotic fluid is more _____(acidic/basic) than vaginal fluid
Basic
What is the definitive test for PROM/PPROM
Amniocentesis with injection of indigo carmine
What is the rate of chorioamnionitis associated with PPROM?
13 - 60%
What is the rate of endometritis associated with PPROM?
2 - 13%
What is the rate of maternal sepsis associated with PPROM?
0.8%
What is the rate of maternal dealth associated with PPROM?
0.14%
What are the most common fetal tracing abnormalities seen with PPROM?
Variable deceleration
What are fetal complication associated with PPROM?
cord prolapse, abruption, fetal death, pulmonary hypoplasia if < 23 wks, neonatal sepsis, CP
PPROM at what gestational age is associated with the highest rate of neonatal death?
PPROM < 22 wga
What is the neonatal survival rate for PPROM < 22wga
14%
What is the neonatal survival rate for PPROM > 22wga
58%
What is the total duration of antibiotic treatment for PPROM?
7 days, 2 days of IV antibotics, 5 days oral antibiotics
What is the IV antibiotic regimen for PPROM?
Ampicillin 2 g q 4 + Erythromycin 250 mg q 6 for 48 hrs
What is the PO antibiotic regimen for PPROM?
Amoxicillin 250 mg + erythromicin 333mg q 8 hrs for 5 days
What outcomes do Antibiotic therapy improve in a patient with PPROM?
Increases latency period, decreases maternal and fetal infection rates
PPROM patients are typically delivered at what gestational age?
34wga
True or false: You can consider expectant management in a PPROM patient 34wga - 36.6wga
True
What are the risks of expectant managment in a PPROM patient following 34wga?
2 x increased risk of maternal infection
Vaginal progesterone decreases the rate of preterm birth by —-.
45%
What does ACOG recommend in terms of administration of Betamethasone (Gestational age and dose) ?
16 wga - 36w6d wga, 250 mg IM q week
Which patients are candidates for vaginal progesterone?
No history of PTD but CL < 2.0 cm
What is the dosage used for vaginal progesterone?
Progesterone 200mg QHS
What is the definition of a history indicated cerclage?
Cerclage placed between 12- 14 weeks gestation in a patient with a history of 3 or more PTD or a second trimester loss
When should CL start for patients with previous PTD?
16 - 24 wga
When should a cerclage be placed in a patient undergoing CL surveillance and history of PTD
When CL < 25 mm and EGA > 24 wks
Would you also recommend treating patients with 17 OHP with a cerclage in place?
yes
ACOG recommends that you screen all pregnant women for GBS at what gestational age?
36w0d - 37wga
What is your treatment plan If a patient has GBS Bacteuria < 10^5 colonies on Urine culture?
No treatment of GBS cystitis, PCN in labor
What is your treatment plan If a patient has GBS Bacteuria >10^5 colonies on Urine culture?
Treatment of GBS cystits and PCN in labor
What are the indications for GBS treatement in labor of a patient with unknown status?
< 37wga. ROM > 18 hrs, Temp > 38
If a patient was GBS positive in a prior pregnancy, what is the risk of recurrent colonization?
50%
What is the optimal duration of GBS in labor?
4 hours, 2 dose
At what time point of PCN administration is there a decrease in GBS colony count and adequate bactericidal levels in Amniotic fluid?
After 2 hrs of administration
What is the regimen for PCN to treat GBS?
Penicillin G 5 million Units IV load then 3 million units q 4 hrs until delivery
What is the regimen for Ampicillin to treat GBS?
Ampicillin 2 g IV load, 1 g Ampicillin q 4 hrs until delivery
What regimen should be used to treat GBS in a patient with a low risk PCN allergy (nonurticarial maculopapular rash without systemic or respiratory symptoms?)
Cefazolin 2g IV load then 1 g q 8 hrs until delivery
What regimen should be used in a patient with a high risk PCN allergy (systemic symptoms, anaphylaxis)?
Clindamycin 900 mg IV q 8 hrs or Vancomycin 20 mg/kg IV q 8 hrs
What must be ordered on GBS testing for a patient with PCN allergy?
susceptibility testing
If susceptibility testing was not done for a patient with GBS and an allergy to PCN, what is the drug of choice?
Vancomycin 20 mg/kg IV q 8