preterm labor and birth special population

what percent of born preterms completed less than 37 weeks of gestation in 2021

10.5%

what is a preterm infant

20-37 weeks gestation

what is meant by small to date

term baby

weighs less than 2500 g at birth

what is 2500g in normal units 

5lbs 8oz 

what is considered very low birth weight

<1500g (3lbs 5oz)

what does survival rate increase with

increased gestational age and birth weight

what is the survival rate of infants weighing 750-1000 grams 

75-80% 

what infant weight is assocaited with high mortality rate

<750g

what is the survival rate at 24 weeks

43%

what is the survival rate at 35 weeks

74%

what is the survival rate at 26 weeks

83%

where is the greatest gain made by prolonging pregnancy 

beyond 24 weeks gestation 

what is survival rate by 30 weeks gestation

90%

when do 90% of preterm births take place

30-36 weeks

what are the etiologies of preterm birth 

premature rupture of membranes (PROM) 

multiple gestations

gestational hypertension/preeclampsia/eclampsia

incompetent cervix

placenta abruptio/previa

fetal growth restriction (UGR)

chorioamnionitis/infections

genetic abnormality

what are other etiologies of preterm birth 

young age (<18) 

low socioeconomic status

trauma

smoking 

drug abuse 

what is the definition of preterm labor

regular painful uterine contractions that produce cervical effacement and dilation before 37 weeks gestation

what is the criteria for the diagnosis of preterm labor

gestational age between 20-37 weeks

at least 4 documented uterine contractions in 20 minutes

pelvic examination

what will be observed on pelvic exam when diagnosing preterm labor 

cervical effacement 80%

cervical dilation of at least 2cm 

what is the management of preterm labor

intravenous hydration and best rest

fetal heart rate monitoring

ultrasonograohy for gestational age and weight

speculum examination to rule out premature rupture of membranes (PROM)

analyze amniotic fluid for fetal lung maturity and to rule out infection

what is teh criteria to use tocolytic therapy 

magnesium sulfate 

nifedipine and prostaglandin synthetase inhibitors 

gestational age between 20 and 34 weeks 

fetal weight under 2500 g

absence of fetal distress

what are the benefits of tocolytic therapy

decreased neonatal morbidity and mortality

what are the risks of tocolytic therapy

maternal and/or fetal sepsis

maternal side effects

further compromise of distressed fetus

what are absolute contraindications to tocolytic therapy 

fetal death 

fetal distress warranting immediate delivery 

chorioamnionitis 

severe hemorrhage 

severe chronic HTN and/or PIH 

what are relative contraindications to tocolytic therapy

cervical dilation >4cm

ruptured membranes

what is the “summary for stopping labor”

no infections

no rupture of membrane