Preterm Labour

Question 1

What define a pre-term labour

Answer 1

Onset of labour before 37 weeks.

Question 2

What causes premature labour?

Answer 2

generaly due to underlying inflammatory response and subsequent prostaglandin release

E,g:
1. Intrauterine Infections
2. Placental Ischaemia/decidual haemorrhage
3. Uterine Strech
4. Foetal / Maternal Stress

Question 3

How can intrauterine infection cause preterm labour?

Answer 3

host inflammatory response and mediator release against infection can trigger labour

Question 4

How can Uterine strech cause preterm labour?

Answer 4

Uterine stretch caused by: multiple gestation, polyhydramnios

Myometrial stretch can increase oxytocin receptors, inflammotry cytokine and prostaglandins

Question 5

how can uteroplacental ischaemia cause preterm labour

Answer 5

uteroplacental ischaemia caused by spiral artery maladaptation, microthrombosis, anterpartum haemorrhage

Thrombin activation leads to uterine contractions

Question 6

how can foetal / maternal stress cause preterm labour

Answer 6

INcreased activation of HPA axis - increased ACTH / cortisol

Question 7

How is preterm labour prophylactically managed?

Answer 7

Women who have a hsitory of preterm labour and cerival length <25mm are offered treatment with:

-Vaginal Progesterone
-Cervical cerclage (way of keeping your cervix closed during pregnancy to prevent premature birth due to incompetent (weakened) cervix. )

Question 8

How is preterm labour diagnosed

Answer 8

Term labour:
Hx, Abdo / vaginal exam, Observation

+
Speculum examination to assess P-PROM
+
Transvaginal US to measure cervical length

Question 9

How is pre-term labour managed?

Answer 9

Maternal corticosteroids - Betamethasone or dexamethasone
Aids foetal lung malnutrition
(Indicated if labour<34 weeks)

+
MgSo4 (30-34 wks) Neuroprotective
(Reduces % of intraventricular haemorrhage)

+
Tocolysis - Nifedipines
(Contraction suppression)

+
Term labour management and monitoring

Question 10

What’s the definition of prelabour rupture of membrane PROM?

Answer 10

Spontaneous rupture of membranes before the onset of labour at term (after 37 weeks
gestation).

Most women w/ PROM go into normal labour within 24hr

Question 11

How is PROM Ivx?

Answer 11

Clinically diagnosed
//
Speculum examination

Question 12

How is PROM TX?

Answer 12

Monitering and awaiting normal labour

2nd line: Labour Induction

Question 13

what is PPROM preterm prelabour rupture of membrane

Answer 13

Rupture of membranes before 37 weeks without spontaneous labour.

Question 14

How is PPROM dx?

Answer 14

Speculum examination - Pooling of amniotic fluid

Question 15

How is PPROM tx?

Answer 15

Prophylactic abx
– PO erythromycin for 10ds/until labour established