3.6 - Preterm Labour and PPROM Flashcards
What is considered Preterm labour?
Labour <37 weeks
If <24 weeks => before viability => miscarriage
What is the normal range for delivery?
37-42 weeks
How do you predict Pre-term birth?
1) Partosure via endocervical swab
2) Transvaginal US checking for cervical shortening (<2.5cm)
What does Partosure measure for
Foetal Fibronectin
What is foetal fibronectin?
Glue like protein that binds foetal membranes. This sheds close to delivery (indicating glue is falling off) => should be absent from vaginal secretions until 36 weeks GA.
Note: It has a good negative predictive value => it can predict if there will not be a pre-term delivery rather than confirming there will be one
How can you prevent Pre-term birth?
1) IM progesterone injections (33% success rate)
2) Cervical Cerclage
3) Tocolysis (only used for short term)
What is Cervical Cerclage?
When is it typically performed?
Cervical cerclage isnt routinely performed. What patients should recieve this?
It is the prophylactic suturing of the cervix
typically performed at 14-16 weeks GA
Performed in patients with cervical incompetence => those with many LLETZ procedures for cervical cancer or a history of pre-term birth due to many reasons such as multiparity or Ehler Danlos
Tocolysis should only be used for short term use. When are they used?
Tocolysis should only be used for short term delay. The only real use cases are:
1) Delay for enough time for steroids to be administered
2) Delay for transfer to a tertiary centre
RF for Preterm delivery
Give 5 pregnancy related and 3 non-pregnancy related causes
Pregnancy-related:
1) Multiple Pregnancy
2) Premature rupture of membranes (Iatrogenic/pathologic)
3) Cevical incompetence (2 or more LLETZ procedures)
4) Placenta Previa
5) Placental Abruption
6) Polyhydramnios
7) Chorioamnionitis
8) Pre-eclampsia
Non-pregnancy related
1) Extremes of reproductive age
2) Smoking
3) Drug use
4) Uterine abnormalities
5) 2 or more LLETZ Procedures!
Give the diagnostic definition of preterm labour
AKA including diagnostic parameters
Definition of Labour + Definition of Preterm =>
Regular painful contraction with cervical change and dilatation <37 weeks
Give 5 consequences of Pre-term birth
1) RDS
2) NEC
3) IVH
4) Periventricular leukomalacia
5) PDA - Patent Ductus Arteriosis
6) Cerebral Palsy
7) Intellectual impairment/mental delay
8) Increased risk of sepsis
9) Neonatal jaundice
Define PROM?
Define PPROM?
Define Prolonged PROM
PROM = Preterm rupture of membranes prior to onset of labour
PPROM = Preterm premature rupture of membranes <37 weeks prior to onset of labour
Prolonged rupture of membranes = ROM >24 hours
Give 4 Ddx for a pregnant woman presenting at 35 weeks after experiencing a sudden gush of fluid
PPROM -Preterm, premature ROM
Urinary incontinence
Vaginal discharge (from infection etc)
High amniotic leak
Labour (if followed by regular contractions)
Use this to ask questions in a history
A patient at 35 weeks gestation presents to you after experiencing a sudden gush of fluid. Give 5 methods to confirm this
Pooling of fluid in the posterior fornix
Amnisure
Vaginal swap pH (nitrazine stick) turns to blue
Microscopy (showing ferning)
Non-diagnostic but US finding reduced amniotic fluid (only indicative)
What does Amnisure test for?
Endocervical swab testing for alpha-Macroglobulin 1 in cervical vaginal fluid
How would you manage a patient presenting with a gush of fluid (assuming it is a PPROM)
At 31 weeks
At 34 weeks
At 36 weeks
For all you need to Admit the patient, full hx and exam, vitals,
bloods to determine if infection (e.g. CRP),
confirm rupture of membranes using diagnostic methods such as amnisure, Prophylactic Erythromycin 250mg PO QDS.
and check for Group B strep (swab) where if positive => Prophylactic Benzylpenicillin or Clindamycin
Provide Surveillance with CTG tracing
31 weeks: 2x 12mg IM Dexamethasone 12 hours apart + 4g IV bolus MgSO4 followed by 1g/hour maintenance dose.
34 weeks: 2x 12mg IM Dexamethasone 12 hours apart
36: Allow for delivery (C-section or natural). No role for steroids or MgSO4.
For all cases, transfer to tertiary center if cannot be facilitated. Thats where tocolytics can be used.
Give your full management plan of a patient presenting with a gush of fluid at 30 weeks. This occurred 28 hours ago. Maternal pyrexia is present
This is a case of prolonged premature rupture of membranes >24 hours
1) Admit the patient, full hx and exam, vitals,
bloods to determine if infection (e.g. CRP),
2) confirm rupture of membranes using diagnostic methods such as amnisure,
3) and check for Group B strep (swab) where if positive => Prophylactic Benzylpenicillin or Clindamycin
4) Foetal monitoring with continuous CTG tracing
5) 2x 12mg IM Dexamethasone 12 hours apart as <34+6 weeks
6) 4g IV bolus MgSO4 followed by 1g/hour maintenance dose
7) There is evidence of maternal pyrexia, Erythromycin 250mg QDS x10 days is recommended
What is the major risk of maternal pyrexia in pregnancy?
Chorioamnionitis
For MCQ. How do you treat chorioamnionitis
Stat dose of Azithromycin 1g PO, then IV 1g amoxicillin for 48 hours before switching to PO 500mg TDS for 5 days
Patients with PPROM are considered high risk especially due to risk of infection.
Give 3 maternal and 3 foetal signs of infection
Maternal:
Foul-smelling vaginal fluid
Contractions/preterm labour
Uterine tenderness
Fever, tachycardia, CRP, increased WCC.
Foetal:
Tachycardia (>160)
Reduced variability on CTG
Alteration in BPP (reduced gross movements, breathing movements, tone, and amniotic fluid volume)
What is the effect of steroid administration on WCC
It raises WCC => if concerned of infection check for CRP and pyrexia to confirm
When should you deliver in PPROM?
All cases should be delivered by 37 weeks. 34-36 weeks with minor suspicion of infection or compromise. If viable and evidence of foetal compromise => delivery immediately via C-section.
What would the consequences of prolonged premature rupture of membranes? (4)
1) Intrauterine infection
2) Placental abruption
3) Cord compression
4) Fetal demise
What is the difference between preterm labour and preterm premature rupture of membranes?
in PPROM, rupture of membranes occurs with or without the presence of contractions. In preterm labour, although it can occur with rupture of membranes, is defined by the onset of regular and frequent contractions <37 weeks
