PTL Flashcards
Cervical changes and regular contractions between 20-37 weeks’ gestation
Preterm labor
Potential long term health issues associated with PTL
cerebral palsy, intellectual disabilities, chronic lung disease, blindness, hearing loss
Any birth that occurs before the completion of 37 weeks of pregnancy, regardless of birth weight.
Preterm birth
Extremely preterm
less than 28 weeks
Very preterm
28-32 weeks
Moderate to late preterm
32-37 weeks
PTL Risk Factors
-Previous PTB (Women with a previous PTB are 2-3x more likely to have another)
-Short cervix
-Multiple gestation
-PPROM (preterm premature rupture of membranes)
-Hormonal changes (from fetal or maternal stress)
-Infections
-African-American Race
PTL Modifiable risk factors
Smoking
Short inter-pregnancy intervals
Low pre-pregnancy weight and poor nutrition
Substance use
Preconception is the best time to address these risks
Signs and symptoms of PTL
Uterine activity
-Uterine contractions that may be painful or painless
Discomfort
-Menstrual-like cramps; low, dull back ache; intestinal cramping; diarrhea; pelvic pressure or heaviness; urinary frequency
Vaginal discharge
-Change in character or amount of usual discharge; SROM; bleeding, spotting
Rupture of the amniotic sac beginning at least 1 hour before the onset of labor before 37 weeks’ gestation
Etiology unknown, often preceded by infection
S/Sx: gush/trickle of fluid from vagina
Preterm Premature Rupture of Membranes (PPROM)
PPROM treatment includes
-Strict sterile technique (Fern/Nitrazine/Amnisure Test)
-No vaginal exams, unless delivery is imminent
-Expectant management (AKA watch and wait) is recommended as long as there are no contraindications
PPROM interventions
-Hospitalization, bed rest PRN
-Fetal surveillance
-Antibiotics
-Tocolytics
-Corticosteroids
Rupture of amniotic sac before labor begins at any gestational age
Premature rupture of membranes (PROM)
PTL test
fFN is a protein that is released into cervical and vaginal secretions when there is disruption of maternal-fetal interface of membranes and decidua (keeps amniotic sac attached to uterine lining)
Tested between 24-34 weeks’ gestation
Specimen must be collected by sterile speculum exam PRIOR to digital examination
Fetal Fibronectin (fFN)
fFN Interpretation
Result is either negative or positive within 24-48 hours
Negative result: likelihood of giving birth within the following week is <1%, predict pregnancy will continue for another 14 days
Positive result: increased chance of preterm birth (labor may start within 7-14 days), specific time frame undetermined by test, continue preventative treatment
fFN contraindications
fFN is NOT tested/valid in the case of:
-Vaginal bleeding
-Intercourse, vaginal exam, or vaginal US within 24 hours prior to collection
-Cervical dilation > 3 cm
-PPROM or bulging membranes
-Open cervical/vaginal sores
Which of the following patients would be eligible for a fFN test?
A. A patient presenting with vaginal bleeding
B. A patient at 31 weeks’ gestation with cramping
C. A patient who had a vaginal ultrasound this morning
D. A patient at 22 weeks’ gestation
B. A patient at 31 weeks’ gestation with cramping
PTL Prevention w/ lifestyle modifications
“Bed rest and pelvic rest”
Individualized/bed rest as needed
Strict bed rest is not evidence based!
Increased clotting tendency
Avoid:
Sexual activity
Riding long distances
Carrying heavy loads
Standing for long periods
Hard, physical labor
Medication to decrease risk of going into PTL
Keeps uterus quite, keep the uterus from contractions
“Maintains pregnancy”
Used in women with previous hx of PTB and/or shortened cervix
Progesterone therapy
Routes progesterone can be given
vaginal gel, suppositories, and IM injection
The use of medications (tocolytics) to inhibit uterine activity
Given between 24-34 weeks
Goal is to suppress uterine activity and buy time to administer antenatal glucocorticoids to accelerate fetal lung maturity (stop/delay labor!)
Tocolysis
Tocolytic contraindications
-If baby’s heart rate drops or spikes, tocolysis will be discontinued
-Not indicated for use before neonatal viability or after 34 weeks
-Fetal demise or lethal fetal anomaly
-Severe pre-eclampsia, eclampsia
-PPROM
-Maternal bleeding with instability
-Chorioamnionitis
Which patient would be eligible for tocolytic therapy?
A. A patient with absent fetal heart tones
B. A patient at 21 weeks’ gestation
C. A patient at 32 weeks’ with gestational diabetes
D. A patient with a 101° F fever
C. A patient at 32 weeks’ with gestational diabetes
Beta-adrenergic receptor agonist: relaxes smooth muscle, decreasing uterine contractility
Given subq injections (common), IV, and orally
Adverse reactions:
Tachycardia, SOB, tachypnea, pulmonary edema, palpitations
Monitor maternal vital signs and FHR
Terbutaline (Brethine)
Calcium channel blocker: reduces contractions by inhibiting calcium from entering smooth muscle cells
Given PO
Adverse reactions:
Hypotension
Monitor maternal vital signs and FHR
Procardia (Nifedipine)
Mineral, anticonvulsant, CNS depressant: interferes with calcium uptake in myometrium cells, reducing muscular ability to contract resulting in smooth muscle relaxation (similar to calcium channel blockers)
Given IV
Adverse reactions:
Hot flushes, sweating, n/v, drowsiness, dizziness, transient hypotension, hypocalcemia, respiratory depression
Monitor maternal vital signs and FHR
Magnesium Sulfate
When preterm birth appears inevitable, magnesium sulfate may be administered to reduce or prevent
neonatal neurologic morbidity (ex: cerebral palsy)
Antidote for magnesium sulfate toxicity
calcium gluconate
Magnesium sulfate is contraindicated in patients w/
myasthenia gravis
Use cautiously in clients with myocardial infection and those with renal disease
Accelerates fetal lung maturity
Promotes release of enzymes to induce production of surfactant in fetal lungs
The most beneficial intervention for the improvement of neonatal outcomes among women who give birth preterm
Antenatal Glucocorticoids
Why should blood glucose levels be monitored when patient is given antenatal glucocorticoids?
Steroids can cause hyperglycemia
