Table 1: Demographic and clinical characteristics by GBS status.

GBS NegativeGBS ColonizedInvasive GBSP Value1P Value2
(N=47,013)(N=12,952)(N=64)

Age at delivery (years)
 Mean (SD)28.7 (6.2)28.0 (6.2)28.1 (6.4)<.0010.95
Race, n ()
 Black or African American14012/44293 (31.6%)5660/12379 (45.7%)39/64 (60.9%)<.0010.05
 White or Caucasian20325/44293 (45.9%)4740/12379 (38.3%)19/64 (29.7%)--
 Other9956/44293 (22.5%)1979/12379 (16.0%)6/64 (9.4%)--
Ethnicity, n ()
 Hispanic7506/44657 (16.8%)1467/12443 (11.8%)2/63 (3.2%)<.0010.08
 Not Hispanic35580/44657 (79.7%)10611/12443 (85.3%)58/63 (92.1%)--
 Other1571/44657 (3.5%)365/1244 (2.9%)3/63 (4.8%)--
Antibiotic use
 Inpatient antibiotic administered1590/47013, 3.4%1271/12952, 9.8%3/64, 4.7%<0.0010.17
 during pregnancy prior to delivery
Risk factors, n ()
 Chronic hypertension3366/47013 (7.2%)1112/12952 (8.6%)16/64 (25.0%)<0.001<.001
 Pre-existing diabetes1294/47013 (2.8%)456/12952 (3.5%)10/64 (15.6%)<0.001<.001
 Autoimmune disorder310/47013 (0.7%)72/12952 (0.6%)0/64 (0%)0.191.00
 Chronic infectious disease3368/47013 (0.8%)106/12952 (0.8%)1/64 (1.6%)0.690.41
 Tobacco use5887/33129 (17.8%)2010/9674 (20.8%)14/51 (27.5%)<0.0010.23

1P value for comparison of GBS negative versus GBS colonized.
2P value for comparison of GBS colonized versus invasive GBS.
3Human immunodeficiency virus, hepatitis B, and hepatitis C.
P value from t-test or Chi-square or Fisher’s exact test.