W11_02 Preterm labour and PPROM Flashcards
define “term pregnancy”
between 37 and 40 weeks
define preterm pregnancy
before 37 weeks
note preterm births account for 75% of perinatal mortality
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what are the three main causes of preterm labour?
spontaneous;
PPROM;
indicated preterm birth
what are three parts of the labour process?
progesterone withdrawal;
oxytocin initiation;
decidual activation (inflammation?)
how long before labour does cervical effacement start
4-8 weeks pre-labour
most risk factors are ASSOCIATED with preterm labour, but are NOT CAUSATIVE
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what’s the biggest risk factor for preterm labour?
previous preterm birth
what lifestyle factors contribute to preterm labour?
smoking, low BMI, high BMI, substance use, stress
what demographic factors contribute to preterm labour?
age, race/ethnicity, SES, education (all maternal factors)
note: women who have bacterial vaginitis have less preterm labour if the infection is treated
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note: multiple pregnancies can increase risk of preterm labour
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note: bleeding is associated with increased risk of preterm labour
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which cervical and uterine issues increase risk for preterm labour?
previous spontaneous preterm birth;
uterine anomaly;
cervical insufficiency;
pervious cervical procedure (LEEP, cone)
note: short inter-pregnancy interval is associated with increased risk of preterm labour
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note: anemia and thrombophilia are two risk factors for preterm labour
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how to diagnose preterm labour?
regular contractions that lead to cervical dilation
what’s fetal fibronectin?
shouldn’t be present in vaginal secretions before 35 weeks; has a high negative predictive value of preterm labour
what’s tocolysis?
medical therapy to try and slow down labour
what are contraindications to tocolysis? (“need to know”)
maternal medical conditions;
chorioamnionitis;
bleeding previa/abruption;
intrauterine growth restriction;
contraindications to specific agents;
mature fetus;
intrauterine fetal demise;
imminent delivery
what’re nifedipine, indomethacin?
tocolysis agents
what’s magnesium sulphate?
slows contractions, but not indicated for tocolysis
note: mag sulphate, antocin/atosiban/tractocil, ritodrine/terbutaline are NOT indicated for tocolysis
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what infection to screen for in a woman with preterm labour?
GBS. If positive, treat. If not, don’t treat. Prevent GBS sepsis in neonate
how do steroids help in preterm labour?
reduction in rates of neonatal death, RDS, IVH, with associated reduction of NEC, resp support, NICU admission, infections in first 48 hours of life
when are steroids beneficial in preterm labour?
26-34+6 weeks. But recommended up to 24 weeks
which steroids to give for preterm labour?
betamethasone and dexamethasone; just one course is good
what does magnesium sulphate do?
maternal neuroprotection (esp eclampsia);
fetal neuroprotection (cerebral palsy)
note: might be good to delay cord clamping in a preterm delivery
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define PPROM
preterm premature rupture of membranes
how can PPROM lead to neonate death?
prematurity;
sepsis;
pulmonary hypoplasia
how to diagnose PPROM?
speculum exam, and the fluid is seen to pool in the posterior fornix. “Ferning” of fluid sample under the microscope
note: check for chorioamnionitis!
can become sepsis in mother AND fetus
what are signs of chorioamnionitis?
maternal vital signs, fetal heart rate, abdominal tenderness/pain, elevation in WBC
what are risks of pre-viable PPROM?
lung hypoplasia, limb contractures
can you give tocolysis in PPROM up to 34 weeks?
no
how to treat PPROM <34 weeks?
antibiotics (erythromycin, ampicillin) shown to help a little
how to manage PPROM >34 weeks?
toss up - it’s prematurity vs. sepsis
