For this sub-group of high-risk women, crude HNE concentration at 14+0 and 15+6 weeks of gestation was modestly predictive of sPTB < 37 weeks (n = 236, AUC 0.63, 0.56 to 0.69), < 34 weeks (n = 241, AUC 0.61, 0.55–0.68), PPROM (n = 241, 0.65, 0.59 to 0.71), objective infection (n = 249, AUC 0.60, 0.53–0.66) and adverse fetal outcome (n = 249, AUC 0.60, 0.54–0.66). This evidence concerns the gene SPTB and preterm premature rupture of the membranes.