Preterm Labor and Prelabor Rupture of Membranes

Question 1

What is the prevention for those with a history of preterm birth?

Answer 1

17-alpha hydroxyprogesterone caproate (17OHP)

250 mg IM weekly from 16-20 weeks’ gestation through 36 weeks’ gestation

Question 2

What is the medication tx for prevention of preterm birth in a patient with a shortened cervix (=2.5 cm) at =24 weeks?

Answer 2

Vaginal progesterone 90 mg gel or 200 mg capsule

daily from diagnosis until 36 weeks

Question 3

How is labor defined?

Answer 3

regular uterine contractions with cervical change

• cervical effacement >/=80%
• cervical dilation >/=3 cm

Question 4

How should you determine if amniotic membranes ruptured?

Answer 4

1. Sterile speculum exam with show pool of fluid in vaginal vault
   - nitrazine testing
   - ferning of amniotic fluid
2. oligohydramnios on ultrasound
3. amnisure

Question 5

What does a fetal fibronectin testing indicate?

Answer 5

if negative, unlikely to deliver within 7-14 days

if positive, chance of delivery within 10 days

Question 6

What are the 5 parts of managing preterm labor?

Answer 6

1. transfer to a higher level of care
2. antenatal corticosteroids if indicated
3. magnesium sulfate for neuroptection if indicates
4. GBS Prophylaxis if indicated
5. Tocolysis if indicated

Question 7

At what gestational age would antenatal corticosteroids be indicated for in the setting of preterm labor?

Answer 7

24-34 weeks gestation

Question 8

What corticosteroids and respective doses are used?

Answer 8

Betamethasone: 12 mg IM every 24 hours X two doses

Dexamethasone: 6 mg IM every 12 hours X four doses

Question 9

In what case would you administer Betamethasone between 34 0/7 to 36 6/7 weeks gestation?

Answer 9

Administer for preterm labor only if at least 3 cm dilated

OR 75% effaced OR spontaneous rupture of membranes

Question 10

What 3 medications are used for tocolysis?

Answer 10

Nifedipine
Terbutaline
Indomethacin

Question 11

What is a contraindication to administration of Nifedipine?

Answer 11

Maternal hypotension

Question 12

What is the dose of Nifedipine for tocolysis?

Answer 12

30 mg loading dose then 10-20 mg orally every 4-6 hrs

Question 13

What are side effects of Nifedipine?

Answer 13

Flushing
Headache
Edema
Dizziness
Nausea

Question 14

What are contraindications to administration of Terbutaline?

Answer 14

Heart Disease
Poorly Controlled Diabetes
Thyrotoxicosis

Question 15

What is the dose of Terbutaline when used for tocolysis?

Answer 15

0.25 mg subcutaneously every 20 minutes for up to three doses

Question 16

When should/can Indomethacin be used in pregnancy?

Answer 16

for increasing estimated gestational age at delivery by an average of 3.5 weeks gestation

• PTL <32 weeks gest
• PTL associated with polyhydramnios

Question 17

What are possible fetal adverse effects of Indomethacin administration?

Answer 17

1. closure of ductus arteriosus

2. oligohydramnios

Question 18

What is the dosing for Indomethacin administration?

Answer 18

50 mg loading dose - oral or rectal

then 25-50 mg orally q4-6h

(200 mg/24 hrs max with 48 hr limit)

Question 19

What is the purpose of magnesium sulfate?

Answer 19

fetal neuropreotection, indicated for 24-32 weeks gestation

- decreases cerebral palsy when administered immediately before and up through delivery

Question 20

What are maternal adverse effects of Magnesium Sulfate administration?

Answer 20

flushing, lethargy, headache, weakness, diplopia, pulmonary edema, cardiac or respiratory arrest

Question 21

What are the two different ways to dose MgSO4

Answer 21

1. 4g loading dose over 20 minutes, then 1 g/hr until birth or for 24 hours
2. 6g loading dose over 20 minutes, then 2g/hr until birth or for 12 hours

Question 22

What is the benefit of delayed cord clamping?

Answer 22

waiting 30-60 seconds after delivery decreases intraventricular hemorrhage in the neonate and decreases need for transfusion.

Question 23

Vacuum delivery is contraindicated under __ weeks gestation due to risk of intracranial hemorrhage.

Answer 23

34 weeks gestational age

Question 24

When should universal screening be performed for GBS?

Answer 24

at 36 0/7 to 37 6/7 weeks gestation
or
at the time the patient presents with PTL

Question 25

Who should receive antimicrobial prophylaxis in labor?

Answer 25

1. GBS bacteriuria found in any concentration during current pregnancy
2. previous birth of an infant with GBS infection
3. Positive GBS vaginal-rectal screening culture

Question 26

Who should receive antimicrobial prophylaxis in labor if GBS status is unknown?

Answer 26

any of the following risk factors:

1. ROM >18 hrs
2. T >100.4’F (38’C)
3. <37+0 weeks’ gestation
4. Intrapartum nucleic acid amplification test (NAAT) (+) GBS
5. Intrapartum NAAT (-) GBS risk factors development

Question 27

What is the first line treatment for GBS?

Answer 27

Penicillin (PCN) or ampicillin

Question 28

What is second line treatment for GBS/for mild PCN allergy?

Answer 28

Cefazolin

unless allergy was anaphylaxis or urticaria

Question 29

What is treatment for GBS in patient with severe PCN allergy?

Answer 29

Clindamycin

but MUST have culture proven sensitivity to this antibiotic – as resistance can be as high as 25%

Question 30

For severe PCN allergy and Clindamycin resistant GBS, what is the treatment?

Answer 30

Vancomycin

Question 31

What is the GBS dose of Penicillin G?

Answer 31

Loading Dose: 5 million units

then 3 million units q4h

Question 32

What is the GBS dose of Ampicillin?

Answer 32

Loading Dose: 2g

then 1g q4h

Question 33

What is the GBS dose of Cefazolin?

Answer 33

Loading Dose: 2g

then 1g q8h

Question 34

What is the GBS dose of Clindamycin?

Answer 34

900mg q8h

Question 35

What is the GBS dose of Vancomycin?

Answer 35

20 mg/kg (2g max) q8h