Preterm birth is the most significant problem encountered in obstetrics in the developed world. Genetic factors are thought to play a role in a proportion of preterm births, and candidate genes have been studied in several areas relevant to parturition. Abnormal cervical function, a clinical spectrum, including cervical insufficiency (CI), is a contributing factor to the overall problem of preterm birth. There are many risk factors and etiologies for CI. However, it is becoming clear that, at least in part, a genetic predisposition to CI plays a role in the condition. Specifically, genes related to connective tissue metabolism and inflammation have been shown to be associated with CI.