Preterm labour: update on prediction and prevention strategies

The incidence of preterm birth is increasing and continues to be a significant cause of neonatal mortality and morbidity. Techniques now exist that can accurately predict early birth. Prevention can therefore be targeted, although effective measures that improve outcome are yet to be established.

Obtaining an accurate history is the first step in identifying high-risk women. Clinicians then rely on other predictors such as fetal fibronectin, cervical length assessment and biochemical markers. Research should focus on the combination of noninvasive markers targeted at high-risk women as a screening tool, determining not only appropriate diagnostic levels for positive tests, but also sufficiently large studies should be performed to determine the predictive values of these tests. Interventions to prevent delivery and improve neonatal outcome remain unsatisfactory, mainly comprising tocolysis, cerclage, progesterone and, in some cases, antibiotics. Women who would most benefit from these interventions are difficult to identify and an appreciation of the pathophysiology in an individual woman, such as the relevance of the inflammatory status of the endocervix, may be important in tailoring intervention.

An improved understanding of the mechanisms underlying the pathological process in preterm birth will allow screening and interventions to be appropriately targeted.