TABLE 5.
Maternal Risk Factors for Early-Onset GBS Sepsis at the Time of Delivery and Maternal Clinical Signs Within 72 Hours Before Delivery for Infants With Invasive Early-Onset Infection Born to Women With Chorioamnionitis, 2006–2009
| Maternal Risk Factors at Delivery or Clinical Signs Within 72 Hours Before Delivery | Overall | Infant Status at Birth (≤6 Hours) | P | |
|---|---|---|---|---|
| Symptomatic | Asymptomatic | |||
| All cases, N | 229 | 200 | 29 | |
| Risk factor, n (%) | ||||
| Previous infant with GBS disease | 0 | 0 | 0 | |
| GBS bacteriuria during current pregnancy | 10 (4) | 10 (5) | 0 (0) | .62 |
| Intrapartum fevera | 79 (35) | 63 (32) | 16 (57) | .01 |
| Delivery <37 weeks | 148 (65) | 142 (71) | 6 (21) | <.001 |
| Rupture of membranes ≥18 hours | 100 (44) | 93 (47) | 7 (25) | .04 |
| At least 1 risk factor above | 202 (89) | 180 (90) | 22 (79) | .10 |
| Symptom, n (%) | ||||
| Maternal feverb | 87 (38) | 67 (34) | 20 (69) | <.001 |
| Uterine or abdominal tenderness | 52 (23) | 50 (25) | 2 (7) | .03 |
| Foul-smelling discharge or amniotic fluid | 35 (15) | 33 (17) | 2 (7) | .27 |
| Maternal tachycardia (>100 beats per minute) | 96 (42) | 83 (42) | 13 (45) | .84 |
| At least 1 symptom above | 162 (71) | 137 (69) | 25 (86) | .05 |
| Maternal fever alone | 30 (13) | 21 (11) | 9 (31) | .006 |
| Clinical chorioamnionitis,c n | 152 | 128 | 24 | |
| Risk factor, n (%) | ||||
| Previous infant with GBS disease | 0 | 0 | 0 | |
| GBS bacteriuria during current pregnancy | 7 (5) | 7 (5) | 0 (0) | .60 |
| Intrapartum fever | 74 (49) | 58 (45) | 16 (70) | .04 |
| Delivery <37 weeks | 93 (62) | 91 (71) | 2 (9) | <.001 |
| Rupture of membranes ≥18 hours | 70 (46) | 65 (51) | 5 (22) | .01 |
| At least 1 risk factor above | 140 (93) | 123 (96) | 17 (74) | .002 |
| Symptom, n (%) | ||||
| Maternal fever | 80 (53) | 60 (47) | 20 (83) | .001 |
| Uterine or abdominal tenderness | 49 (32) | 47 (37) | 2 (8) | .008 |
| Foul-smelling discharge or amniotic fluid | 32 (21) | 30 (23) | 2 (8) | .11 |
| Maternal tachycardia (>100 beats per minute) | 75 (49) | 64 (50) | 11 (46) | .82 |
| At least 1 symptom above | 134 (88) | 111 (87) | 23 (96) | .31 |
| Maternal fever only | 27 (18) | 18 (14) | 9 (38) | .02 |
| Histologic chorioamnionitis only,d n | 77 | 72 | 5 | |
| Risk factor, n (%) | ||||
| Previous infant with GBS disease | 0 | 0 | 0 | |
| GBS bacteriuria during current pregnancy | 3 (4) | 3 (4) | 0 (0) | .99 |
| Intrapartum fever | 5 (6) | 5 (7) | 0 (0) | .99 |
| Delivery <37 weeks | 55 (71) | 51 (71) | 4 (80) | .99 |
| Rupture of membranes ≥18 hours | 30 (39) | 28 (39) | 2 (40) | .99 |
| At least 1 risk factor above | 62 (81) | 57 (79) | 5 (100) | .58 |
| Symptom, n (%) | ||||
| Maternal fever | 7 (9) | 7 (10) | 0 (0) | .99 |
| Uterine or abdominal tenderness | 3 (4) | 3 (4) | 0 (0) | .99 |
| Foul-smelling discharge or amniotic fluid | 3 (4) | 3 (4) | 0 (0) | .99 |
| Maternal tachycardia (>100 beats per minute) | 21 (27) | 19 (26) | 2 (40) | .61 |
| At least 1 symptom above | 28 (36) | 26 (36) | 2 (40) | .99 |
| Maternal fever only | 3 (4) | 3 (4) | 0 (0) | .99 |
All maternal risk factor information was missing for 1 infant who was asymptomatic within 6 hours of birth and whose mother had clinical chorioamnionitis. Maternal temperature within 72 hours before delivery was missing for 1 infant who was symptomatic within 6 hours of birth and whose mother had clinical chorioamnionitis. Statistical significance for a difference between the percentage in symptomatic versus asymptomatic infants was derived by Fisher’s exact test.
Maternal intrapartum fever was defined as a temperature ≥100.4°F (38.0°C) after onset of labor leading to delivery.
Maternal fever was defined as any temperature ≥100.4°F (38.0°C) in the 72 hours before delivery without regard to onset of labor.
Chorioamnionitis documented in the mother’s medical record, with or without histologic findings from placental pathology.
Histologic chorioamnionitis documented from placental pathology without documentation of chorioamnionitis in the mother’s medical record.