ABSTRACT
Defi nition ....................................................................................................... 132
Prevalence ................................................................................................... 132
Classifi cation .............................................................................................. 134
Aetiology ........................................................................................................ 134
Clinical features of preterm labour .............................................. 135
Clinical features of preterm pre-labour rupture of the
membranes ....................................................................................... 137
Clinical features of late miscarriage ........................................... 137
Management of symptomatic women ....................................... 138
Management of high-risk asymptomatic women .............. 140
Preterm or early delivery occurs after viability but before 37 weeks gestation. Spontaneous preterm labour and preterm
pre-labour rupture of membranes account for approximately two-thirds of preterm births with the remainder resulting from
medical or obstetric complications. Second trimester or late miscarriage occurs prior to viability. It is particularly distressing
to the woman and her family because the pregnancy has become obvious abdominally and the mother may have started
to notice fetal movements. Currently, the ‘grey zone’ for viability is around 23 weeks. Early births remain the predominant
cause of perinatal mortality and morbidity, particularly those occurring between viability and 32 weeks gestation. The
aetiology underlying late miscarriage and spontaneous preterm delivery varies with gestational age.
