Risk-scoring systems for the prevention of preterm birth

Identification of women whose pregnancies are at higher than average risk of preterm birth would allow the possibility of providing the women with higher level antenatal care with the aim of preventing the preterm birth. Preterm birth (before 37 completed weeks' gestation) is a major public health problem worldwide, and occurs in 6% to 10% of births in high-income countries. The proportion of pregnancies which end prematurely, between 20 and 36 weeks, has not fallen in recent years. Perinatal interventions, both before birth (transfer of women to tertiary care, antenatal steroids), and after birth (intensive care, surfactant) have markedly improved perinatal outcomes. A number of scoring systems of risk factors associated with preterm birth have been used. Systematic, objective measures can include age, marital status, socio-economic factors, smoking, threatened miscarriage, previous low birthweight baby, previous stillbirth, maternal weight and height. Their ability to identify women at increased risk of preterm birth, and subsequently to prevent preterm birth, has not been evaluated by randomised controlled trials. The literature search for this review revealed no trials of the use of risk-scoring systems to prevent preterm birth. There are a number of ethical issues involved in the decision to implement risk scoring that have not been evaluated; for example, an intervention with potential morbidity and may be used, or used more frequently with no evidence of more favourable outcomes, or the woman may prefer not to disclose some sensitive information included in the measures. There is a need for prospective studies that evaluate the use of risk-scoring systems to prevent preterm birth, including an assessment of their impact on women's well-being. If these prove promising, they should be followed by an adequately powered, well-designed randomised controlled trial.

Authors' conclusions: 

The role of risk-scoring systems in the prevention of preterm birth is unknown.

There is a need for prospective studies that evaluate the use of a risk-screening tool designed to predict preterm birth (in combination with appropriate consequent interventions) to prevent preterm birth, including qualitative and/or quantitative evaluation of their impact on women's well-being. If these prove promising, they should be followed by an adequately powered, well-designed randomised controlled trial.

Read the full abstract...
Background: 

Identification of pregnancies that are higher risk than average is important to allow the possibility of interventions aimed at preventing adverse outcomes like preterm birth. Many scoring systems designed to classify the risk of a number of poor pregnancy outcomes (e.g. perinatal mortality, low birthweight, and preterm birth) have been developed, but they have usually been introduced without evaluation of their utility and validity.

Objectives: 

To determine whether the use of a risk-screening tool designed to predict preterm birth (in combination with appropriate consequent interventions) reduces the incidence of preterm birth and very preterm birth, and associated adverse outcomes.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2015).

Selection criteria: 

All randomised or quasi-randomised (including cluster-randomised) or controlled clinical trials that compared the incidence of preterm birth between groups that used a risk-scoring instrument to predict preterm birth with those who used an alternative instrument, or no instrument; or that compared the use of the same instrument at different gestations.

The reports may have been published in peer reviewed or non-peer reviewed publications, or not published, and written in any language.

Data collection and analysis: 

All review authors planned to independently assess for inclusion all the potential studies we identified as a result of the search strategy. However, we did not identify any eligible studies.

Main results: 

Searching revealed no trials of the use of risk-scoring systems for preventing preterm birth.

Share/Save