Preterm labour, Premature rupture of membranes and Tococlysis Flashcards
What is the definition of preterm labour?
Preterm labour is the occurrence of regular uterine contractions with cervical change between 28 weeks and 36 weeks and 6 days of gestation.
How many uterine contractions per hour are typically required to cause cervical change?
More than four uterine contractions per hour are needed to cause cervical change.
What is the significance of preterm birth?
Preterm birth is a leading cause of neonatal morbidity and mortality, low birth weight, and accounts for 2/3 of infant deaths.
What proportion of preterm births are idiopathic?
Approximately half of all preterm births are idiopathic.
Name some risk factors for preterm labour.
Risk factors include previous preterm labour, infections, cervical or uterine abnormalities, low prepregnancy weight, smoking, and stress.
How can preterm labour be prevented?
Preterm labour can be prevented with progestin administration between 16–20 weeks and 36–37 weeks, reducing risk by 30%.
List common symptoms and signs of preterm labour.
Symptoms and signs include uterine contractions, cervical dilation, vaginal bleeding, increased discharge, and passage of ‘show.’
How is the gestational age of a fetus estimated?
Gestational age is estimated from the last menstrual period (LMP) or early ultrasound scans.
What investigations are conducted for preterm labour?
Investigations include fetal fibronectin tests, amniocentesis, swabs for infections, and ultrasound scans.
What are the differential diagnoses for preterm labour?
Differential diagnoses include preterm contractions (no cervical change) and cervical insufficiency (cervical change without contractions).
Name complications associated with preterm birth.
Complications include respiratory distress syndrome (RDS) and neurological injuries.
How is treatment for preterm labour categorized?
Treatment is categorized as expectant or intervention, depending on gestational age and contraindications.
What are the components of expectant management for preterm labour?
Expectant management includes bed rest, corticosteroids, antibiotics, and magnesium sulfate for fetal neuroprotection.
What is tocolysis?
Tocolysis involves using medication to suppress uterine contractions and delay labour.
What are the indications for tocolysis?
Indications for tocolysis include high-risk pregnancies, positive fibronectin tests, short cervix, and cervical changes.
Name five types of tocolytic drugs.
Types of tocolytic drugs: beta-mimetics, magnesium sulfate, calcium channel blockers, prostaglandin synthase inhibitors, oxytocin antagonists.
What are the limitations of beta-mimetic adrenergic agents like ritodrine?
Beta-mimetics are limited by dose-related cardiovascular side effects in both mother and fetus.
How does magnesium sulfate act as a tocolytic?
Magnesium sulfate inhibits calcium uptake into smooth muscle cells, reducing uterine contractility.
What is the mechanism of action for calcium channel blockers like nifedipine?
Calcium channel blockers like nifedipine block calcium uptake via voltage-dependent channels in uterine muscle cells.
What is the definition of premature rupture of membranes (PROM)?
PROM is the rupture of membranes before the onset of active labour and is prolonged if more than 24 hours.
How is PROM diagnosed clinically?
PROM is diagnosed by pooling of amniotic fluid, alkaline reaction on Nitrazine paper, and fern patterns on slides.
What are the clinical features of chorioamnionitis?
Clinical features of chorioamnionitis include fever, uterine tenderness, tachycardia, foul-smelling amniotic fluid, and maternal leukocytosis.
What are some differential diagnoses for PROM?
Differential diagnoses include physiological vaginal discharge and vaginal infections like bacterial vaginosis.
What are the key components of PROM treatment?
PROM treatment includes antibiotics, corticosteroids, and magnesium sulfate for neuroprotection.
What percentage of PROM cases occur after 37 weeks of gestation?
Ninety-five percent of PROM cases occur after 37 weeks of gestation.
What are some complications associated with PROM?
Complications of PROM include infection, preterm labour, and neonatal complications.
How is fetal neuroprotection achieved in cases of preterm labour?
Fetal neuroprotection is achieved using magnesium sulfate between 24 and 32 weeks of gestation.
What is the purpose of corticosteroids in managing preterm labour?
Corticosteroids promote fetal lung maturity and reduce neonatal complications.
Why is magnesium sulfate administered between 24–32 weeks?
Magnesium sulfate protects against neurological injuries, such as cerebral palsy, in preterm infants.
What are some social factors contributing to preterm labour?
Social factors contributing to preterm labour include low socioeconomic status, short interpregnancy intervals, smoking, and stress.
