Preterm Labour

Question 1

Risk factors

Answer 1

Previous preterm labour
Intrauterine infections
Extrauterine infections
Cervical causes
Fetal (chrom abnormality)
Uterine abnormalities
Twins
Trauma
increasing age
Low BMI
Smoking
Alcohol
APH
PET
Utero-placental insufficiency

Question 2

PTB related to neonatal death and childhood neurological disabilities

Answer 2

75-90% (not due to lethal congenital malformations)

50% of childhood neurological disabilities

Question 3

Risk of future preterm birth after 1 and 2

Answer 3

15%

41%

Question 4

BV treatment

Answer 4

Metronidazole 400mg PO BD 7/7 after 13 weeks

Question 5

Ureaplasma

Answer 5

Uncertain if tx is indicated

Treat with erythromycin

Question 6

FFN

Answer 6

Protein produced by fetal cells found at the interface of the chorion and decidua
99.5% negative predictive value
Should not be detectable between 16-35 weeks

Question 7

Contraindications to tocolysis

Answer 7

Gestational age > 34 weeks
APH
Intrauterine infection
Fetal anomaly not compatible with life
Maternal indication for birth exists (PET)
Pathological fetal heart tracing 
Maternal refusal of treatment

Question 8

When to use mgso4

Answer 8

<30 and PTB is planned or expected within 24 hours

Question 9

Mgso4 dosing for neuroprotection

Answer 9

4g loading dose (over 20min)
1g/hr maintenance
Continue regime until birth or for 24 hours

Question 10

Reversal of mgso4

Answer 10

Calcium gluonate (1g(10ml of 10% solution) slowly via IV over 10 minutes)

Question 11

Cerebral palsy from PTB percentage

Answer 11

45%

Question 12

Most frequent neurological impairments with PTB

Answer 12

CP

Cognitive dysfunction

Question 13

Mgso4 mechanism of action

Answer 13

Neuroprotection
Prevents post-hypoxia brain injury by blocking the excess release of glutamate in the calcium channel

Fetal brain susceptible to damage from glutamate release

Question 14

Side effects of mgso4

Answer 14

Flushing
Sweating
Sensation of warmth
Nausea
Vomiting
Headache
Palpitations
Pulmonary oedema (rare)

Question 15

Hypermagnesia in the neonate

Answer 15

Hyporeflexia
Poor suck
Resp depression (rare)

Question 16

Pathophysiology of RDS

Answer 16

Structurally immature lungs with surfactant deficiency in production and function (type 2 pneumocytes)

Surfactant spread as a thin film at the air-liquid interface of the alveolar surface, lowered surface tension and prevents alveolar collapse and reduces pressure required for alveolar inflation

Develop atelectasis and abnormalities of lung function
Low functional capacity
Low tidal volume
Large physiological dead space
Ventilation-perfusion mismatch & right to left intrapulmonary shunting —>limits excretion of CO2 and o2 sat of pulm venous blood—>respiratory acidosis and hypoxaemia

Question 17

Test to confirm PPROM

Answer 17

Insulin-like growth factor binding protein - 1
OR
Placental alpha-microglobulin-1 test