Context

A strong and consistent association between treatment for cervical disease and subsequent preterm birth has been established.1 The association with preterm birth is stronger when more aggressive forms of treatment (eg, knife cones) are considered.1 Several studies have shown a biological gradient, with a greater risk of preterm delivery with increasing amount of tissue removed.2 ,3 Two meta-analyses have assessed the importance of the comparison group when assessing the risk of preterm birth,4 ,5 but they did not consider the amount of tissue removed. This systematic review and meta-analysis examines the impact of various types of treatment for cervical preinvasive disease on obstetric outcomes and how this risk could …