Improving perinatal Group B streptococcus screening with process indicators

Group B streptococcus (GBS) neonatal infection can be prevented by screening pregnant women for GBS colonization from the 34th to the 38th week of gestation, as has been recommended in France since 2001. We assessed guideline adherence among midwives and obstetricians.

From 2006 to 2008, new and mandatory GBS data were added to the obstetric database. We merged the latter with a bacteriological database and a paediatric database and defined process indicators for pregnant women who delivered from the 37th week of gestation in the hospital of Poitiers and for neonates hospitalized for a GBS infection from 2006 to 2008.

We abstracted 5997 pregnant women (1942 in 2006, 1975 in 2007 and 2080 in 2008) and 84 neonates (17 in 2006, 32 in 2007 and 35 in 2008). GBS pregnancy colonization prevalence was 15%, 13% and 18% respectively. Availability of GBS screening status was stable (96%, P = 0.15). The rate of GBS screening during pregnancy increased significantly (86% to 90%, P = 0.002). Percentage of correct-term screening increased significantly (89% to 96%, P < 0.001). Percentage of women who received intra-partum antibiotic prophylaxis decreased significantly (84% to 70%, P = 0.001). Percentage of women who received correct intra-partum antibiotic prophylaxis was stable (75%, P = 0.65). Percentage of neonates whose mother had been correctly screened but negative was 77%, 67% and 68% respectively (P = 0.61).

Our mandatory database entailed guideline adherence over a short lapse of time and resulted in a significant increase of the screening rate at the correct term. However, circumstances where neonates are infected still remain. Screening test performance needs to be re-evaluated.