Preterm Labor and Prelabor Rupture of Membranes Flashcards
What is the prevention for those with a history of preterm birth?
17-alpha hydroxyprogesterone caproate (17OHP)
250 mg IM weekly from 16-20 weeks’ gestation through 36 weeks’ gestation
What is the medication tx for prevention of preterm birth in a patient with a shortened cervix (=2.5 cm) at =24 weeks?
Vaginal progesterone 90 mg gel or 200 mg capsule
daily from diagnosis until 36 weeks
How is labor defined?
regular uterine contractions with cervical change
- cervical effacement >/=80%
- cervical dilation >/=3 cm
How should you determine if amniotic membranes ruptured?
- Sterile speculum exam with show pool of fluid in vaginal vault
- nitrazine testing
- ferning of amniotic fluid - oligohydramnios on ultrasound
- amnisure
What does a fetal fibronectin testing indicate?
if negative, unlikely to deliver within 7-14 days
if positive, chance of delivery within 10 days
What are the 5 parts of managing preterm labor?
- transfer to a higher level of care
- antenatal corticosteroids if indicated
- magnesium sulfate for neuroptection if indicates
- GBS Prophylaxis if indicated
- Tocolysis if indicated
At what gestational age would antenatal corticosteroids be indicated for in the setting of preterm labor?
24-34 weeks gestation
What corticosteroids and respective doses are used?
Betamethasone: 12 mg IM every 24 hours X two doses
Dexamethasone: 6 mg IM every 12 hours X four doses
In what case would you administer Betamethasone between 34 0/7 to 36 6/7 weeks gestation?
Administer for preterm labor only if at least 3 cm dilated
OR 75% effaced OR spontaneous rupture of membranes
What 3 medications are used for tocolysis?
Nifedipine
Terbutaline
Indomethacin
What is a contraindication to administration of Nifedipine?
Maternal hypotension
What is the dose of Nifedipine for tocolysis?
30 mg loading dose then 10-20 mg orally every 4-6 hrs
What are side effects of Nifedipine?
Flushing Headache Edema Dizziness Nausea
What are contraindications to administration of Terbutaline?
Heart Disease
Poorly Controlled Diabetes
Thyrotoxicosis
What is the dose of Terbutaline when used for tocolysis?
0.25 mg subcutaneously every 20 minutes for up to three doses
When should/can Indomethacin be used in pregnancy?
for increasing estimated gestational age at delivery by an average of 3.5 weeks gestation
- PTL <32 weeks gest
- PTL associated with polyhydramnios
What are possible fetal adverse effects of Indomethacin administration?
- closure of ductus arteriosus
2. oligohydramnios
What is the dosing for Indomethacin administration?
50 mg loading dose - oral or rectal
then 25-50 mg orally q4-6h
(200 mg/24 hrs max with 48 hr limit)
What is the purpose of magnesium sulfate?
fetal neuropreotection, indicated for 24-32 weeks gestation
- decreases cerebral palsy when administered immediately before and up through delivery
What are maternal adverse effects of Magnesium Sulfate administration?
flushing, lethargy, headache, weakness, diplopia, pulmonary edema, cardiac or respiratory arrest
What are the two different ways to dose MgSO4
- 4g loading dose over 20 minutes, then 1 g/hr until birth or for 24 hours
- 6g loading dose over 20 minutes, then 2g/hr until birth or for 12 hours
What is the benefit of delayed cord clamping?
waiting 30-60 seconds after delivery decreases intraventricular hemorrhage in the neonate and decreases need for transfusion.
Vacuum delivery is contraindicated under __ weeks gestation due to risk of intracranial hemorrhage.
34 weeks gestational age
When should universal screening be performed for GBS?
at 36 0/7 to 37 6/7 weeks gestation
or
at the time the patient presents with PTL
