sPTB occurred more frequently among participants with the following risk factors (crude OR, Table 3): any ethnic minority (OR: 3.7, 95% CI: 1.4–9.6), low SES (OR: 3.7, 95% CI: 1.6–8.5), being single (OR: 4.5, 95% CI: 1.3–14.9), vaginal bleeding during the first or second trimester (OR: 3.9, 95% CI: 1.6–9.8) and one or more urinary tract infection(s) (UTIs) during pregnancy (OR: 4.7, 95% CI: 1.7–13.1). This evidence concerns the gene SPTB and urinary tract infection.