Obstetrical Complications (Wootton) Flashcards
Preterm Labor (PTL) definition
birth that occurs after 20 weeks but before 36 6/7 weeks
Diagnosis for preterm labor
- uterine contractions
- cervical change
- 2 cm and/or 80% effaced
What are the 4 main pathways for prevention of preterm labor?
- Infection (BV, GBS, gonorrhea/chlamydia)
- Placental-vascular
- Psychosocial stress and work strain (mental and physical stress)
- Uterine stretch (polyhydramnios - increased amniotic fluid and multiple gestations - twins)
The association between the cervix length and PTL
the relative risk for PTL is increased the shorter your cervix
** RR 6.2 for cervical length of 2.5 cm
Screening tools for preterm labor (PTL)
US and fetal fibronectin (FFN)
Evaluation for PTL
cervical exam to assess dilation, effacement and fetal presenting part; external monitoring and oral/IV hydration; cultures for group B strep
Hydration in PTL
hydration and rest will resolve uterine contractions but will NOT stop PTL
Management of PTL
if less than 34 weeks, start tocolysis:
Magnesium sufate - drug of choice
Nifedipine
Prostaglandin Synthetase Inhibitors`
Drug of choice for PTL management when less than 34 weeks
Magnesium sufate; competes with calcium for entry into the cell at the same time of depolarization; provides some neuroprotection (against cerebral palsy)
Nifedipine treatment in PTL
oral agent; inhibits/slows inward current of calcium during the second phase of the action potential
Agent used in extreme prematurity of PTL
Prostaglandin Synthetase Inhibitors; inhibits prostaglandin production that induce myometrial contractions; use on short term basis; can result in oligohydramnios
Agents for fetal lung maturation
glucocorticoids; effects last 7 days; single does of betamethasone is recommended for 34 - 36 weeks at risk for PTL within 7 days
What are the lower limits of viability of a preterm infant?
22 weeks or 500 g
Definition of premature rupture of membranes (PROM)
premature rupture of the membranes before the onset of labor at any gestational age
premature rupture of membranes (PROM) diagnosis
hx: loss of fluid and confirmation of amniotic fluid in vagina
**DO NOT check the cervix; will increase risk of infection!
rupture is confirmed using a sterile speculum