Preterm Delivery

Question 1

what is the definition of preterm delivery

Answer 1

delivery of a neonate between the gestational ages of 24-36 weeks

Question 2

what % of all births are premature

Answer 2

5-8%

Question 3

when is a miscarriage considered ‘late’

Answer 3

16-23+6 gestational weeks

Question 4

how does morbidity risk change with gestational age with premature neonates

Answer 4

At 24 weeks 1/3 die and 1/3 have permanent/long term injury

At 32 weeks <5% have complications/die

34-36 weeks still have complications however, including RDS, increased mortality and subtle behavioural/cognitive problems

Question 5

what are some risk factor for premature birth

Answer 5

Previous history

Pregnancy complications (IUGR/pre-eclampsia)

Fibroids

UTIs

Short interpregnancy window

Lower socioeconomic class

Maternal chronic illness

Multiple pregnancy

Extremes of maternal age

Male gender

Antepartum haemorrhage

Previous cervical surgeryervical su

Uterine abnormalities

Polyhydramnios

Coongeintal foetal abnormalities

Question 6

what’s the mechanism behind polyhydrmanios/multiple pregnancy causing preterm birth

Answer 6

increased stretch from increased internal pressure

Question 7

what % of preterm births are infections present in

Answer 7

60%

Question 8

what is the single most sensitive measurement for detecting risk of premature birth

Answer 8

cervical length, achieved by transvaginal ultrasonography

Question 9

what prevention strategies are available for those at high risk of preterm birth

Answer 9

Progesterone supplementation

Infection Screening

Foetal Reduction (selective abortion in multiple pregnancy)

Treatment of Polyhydramnios (aspiration/NSAIDS)

Treatment of any medical disease

Question 10

what is the role of NSAIDs in prevention of polyhydramnios related premature birth

Answer 10

reduce foetal urine output

Question 11

what are features of premature birth

Answer 11

Painful Contractions 
Cervical Incompitence 
APH
fluid loss 
may be fever/sepsis if infective

Question 12

how should you investigate a ?premature birth

Answer 12

Vaginal exam – unless membranes have ruptured
Dilated cervix confirms diagnosis

Foetal fibronectin assay
Negative indicates delivery in the next week is unlikely

TVS of cervix
Measures cervical length
Anything>15mm indicated preterm delivery is unlikely

CTG

USS

Vaginal swabs

Question 13

how should you manage a confirmed premature birth

Answer 13

if <34 weeks gestation, tocolytic and steroid to promote lung maturation

Infection Screen

If within 12 hours of start of labour and <34 weeks - Magnesium sulphate (neuroprotective)

transfer to NICU and delivery planning

Question 14

what are the contraindications to tocolytics in premature birth

Answer 14

using >24 hours

Presence of maternal infection

Question 15

what is a premature, prelabour rupture of membranes

Answer 15

rupture of membranes <37 weeks not followed by delivery

Question 16

what are complications of a prelabour, preterm rupture of membranes

Answer 16

preterm delivery

foetal infection

pulmonary issues/postural deformities due to lack of liqor

Question 17

what are the clinical features of a prelabour, preterm rupture of membranes

Answer 17

Gush of clear fluid with further leaking

Pool of fluid in posterior fornix is considered diagnostic

Chorioamnionitis presents as: 
Contractions or uterine pain  
Tachycardia  
Fever 
Hypothermia 
Uterine tenderness 
Coloured liquor  
Offensive smelling liquor  

Although clinical features tend to be late

Question 18

how should you investigate a prelabour, preterm rupture of membranes and what do you expect to find

Answer 18

USS may show oligohydramnios, but foetal urine production continues so this may be normal

High vaginal swab, FBC, CRP assesses for infection, lactate indicates the severity of a sepsis

CTG evaluates foetal wellbeing

Question 19

how should you manage a prelabour, preterm rupture of membranes

Answer 19

Risk of preterm delivery is balanced against risk of maternal infection

Usually admitted for at least 48 hours and given steroids

Close maternal and foetal observation

Question 20

In a patient with a prelabour, preterm rupture of membranes, what should you do if they have features of a Uterine infection

Answer 20

IVABx and immediate delivery