[Screening of Streptococcus agalactiae (group B) in the perinatal period]

To determine the carriage rate of Streptococcus agalactiae in a group of pregnant women and evaluate its role in a neonatal infections.

Prospective study between December 1992 and May 1993.

University hospital.

166 patients aged 17 to 41 years (m = 28 yrs) with a gestational age of 32 to 42 wks (m = 39.99 +/- 1.73) were admitted to the delivery suite. All patients had a vaginal swab on admission before any lavage.

The recovery rate of Streptococcus agalactiae (group B) was found to be 7.8% (13/166) in our population. Twelve of the thirteen newborn to colonized mothers (92%) were term newborn as compared to 141 of 153 (92.1%) newborn to non-colonized mothers (p = 0.72). Three of thirteen (23%) colonized mothers had premature rupture of membranes and 23% (3/13) had prolonged labor > 12 h as compared to of 38 (25.1%) and 8 (5.1%) non-colonized mothers (respectively p = 0.58; NS; p = 0.035). No intra-partum fever was reported. All neonates born to colonized mothers had a birth weight > 2,800 g, an average Apgar score of 8.6 while neonates of non-colonized women had a weight > 2,800 g in 89.4% of cases and an average Apgar of 8.8 (p = 0.9). Two (15.4%) newborn infants born to colonized mothers had an early neonatal infection: one had a pneumonia and had a favorable outcome, the other one developed sepsis and meningitis and died on day 3.

Despite the low rate of Streptococcus agalactiae (group B) colonization (found in our population), regular identification of the organism is recommended because of the high risk of neonatal infection with a high mortality. Further studies on a larger group are needed to confirm such an approach.