Onset of labour before 37 weeks Flashcards
Definition of preterm labour
Onset of labour from >20 weeks until 36 + 6 days
Common associations (8)
Lower SES Previous preterm Multiple pregnancy Uterine structural, cervical incompetence Infection and PPROM APH Polyhydramnios \+Fetal fibronectin and short cervical length Poor dental hygeine Low maternal weight
Causes of mortality and morbidity in preterm (7)
Respiratory distress Hypothermia Hypoglycemia Necrotising enterocolitis Jaundice Infection Retinopathy of prematurity
Assessment: mother and fetus
Mother: History-> Bleeding, fluid, discharge Dysuria, frequency, flank pain, fever Polyhydramnios->++girth, ?diabetes Multiples Previous preterm, uterine structural Previous investigations and procedures->CIN, ablation, sutures Family and social history->poor nutrition, smoking, single, coffee, recreational drugs, alcohol, poor dental hygeine. Medical, surgical, obstetric
Fetal;
Movement, lie and presentation
Assess for signs and symptoms:
Pelvic pressure, lower abdominal cramping, lower black pain. Vaginal loss. Regular uterine activity
How is diagnosis made
Presence of regular painful contractions with dilitation and effacement of cervix on sterile speculum/vaginal examination (to avoid in PPROM b/c risk infection)
How id diagnosis of chorioamnionitis made
>37.5 Abdominal pain Uterine tenderness Fetal tachycardia/maternal tachycardia Offensive vaginal discharge
Risk of preterm with previous preterm
4X risk
Key diagnostic features
Risk factors Uterine contraction PPROM \+Cervical dilitation Cervical length
What is threatened preterm labour
Preterm uterine contractions without cervical effacement or dilation
What is involved in diagnosis
Establishing likelihood of delivery
Determining fetal well being
Looking for underlying cause
What gives the best prediction of preterm birth
Fetal fibronectin + cervical ulrasound
When are contractions less likely to be physiological
When >1 in 10 minutes
Physical examination
Vital signs Abdominal palpation Fetal surveillance->CTG and tocograph Sterile speculum: ->identify if ROM ->assess cervix ->high vaginal swab ->test for fetal fibronectin Low vaginal/anorectal GBS swab Cervical dilitation->sterile digital vaginal examination unless ROM, PP USS if available->assess fetal growth and well being
Investigations to confirm premature labour
Fetal firbonectin
High vaginal/cervical swabs for bacterial infection/Chlamydia/->MCS
Low vaginal for GBS
MSU for MCS
What is fetal fibronectin, how performed and when
All women presenting with preterm contractions between 24 and 35 weeks’ gestation, who are not in advanced labour (cervical dilation
When to consider admission (7)
fFN >50ng/ml or Cervical dilation ot Cervical change over 2-4 hours or ROM or Contractions regular and painful or Further Ix/management required or Maternal/fetal concerns
Management on admission
Analgesia Clinical surveillance CTG/fetal monitoring Transvaginal cervical length if available Consult Plan care, prepare for birth
Consider: In utero transfer Antenatal steroids Tocolysis Antibiotics Magnesium sulphate
Management if admission not required
Provide information re: signs and symptoms and returning for care
Arrange follow up as indicated
Antenatal corticosteroid regime
o Betamethasone: 11.4 mg IM then 2nd dose in 24 hours
o Consider 2nd dose at 12 hours if PTB likely within
24 hours
• If risk of PTB remains ongoing in 7 days, repeat dose
Tocolysis regime
• Nifedipine 20 mg oral
• If contractions persist after 30 minutes repeat
Nifedipine 20 mg oral
• If contractions persist after further 30 minutes repeat
Nifedipine 20 mg oral
• Maintenance therapy 20 mg every 6 hours for 48
hours
Discuss with Obstetrician/Paediatrician
• If contraindications exist
• If other options required (Indomethacin, Salbutamol)
Administer antibiotics if
Established labour w/ imminent risk of preterm birth
Evidence of chorioamnionitis
o Ampicillin (or Amoxycillin) 2 g IV initial dose, then
1 g IV every 4 hours
o Gentamicin 5 mg/kg IV daily
o Metronidazole 500 mg IV every 12 hours
If X labour and:
Membranes intact->cease
PPROM->convert to Erythromycin 250mg oral 6qh for 10 days
If hypersensitivity->lincomycin or clindamycin
Vaginal or cesarean birth
Recommend vaginal unless specific CI/maternal condition necessitates C section
Management after threatened preterm labour
Care according to clinical needs
Maternal and fetal assessments
T/F back to referring hospital if feasible
D/C when criteria met
Inform woman, GP, care provider about further recommendations of care
Magneium sulphate regime
• Gestational age 24–30 weeks
• Labour established or birth imminent
o Loading dose: 4 g IV bolus over 20 minutes
o Maintenance dose: 1 g/hour for 24 hours or until
birth – whichever occurs first
