[Value of amnioculture for choosing antibiotic treatment for premature rupture of membranes before 34 weeks gestation].

OBJECTIVE

This study attempts to answer the following question: is systematic amniocentesis an efficient tool for adjusting an antibiotic treatment in case of preterm premature rupture of membranes?

METHODS

Retrospective study of 76 cases of preterm premature rupture of membranes that occurred between January 1994 and February 1997 in a French teaching hospital.

RESULTS

Amniocentesis was impossible for 28 patients (Group I). In this group there was a 46% rate of neonatal sepsis (n=13). Amniocentesis was successful in 48 patients. 24 delivered within 48 hours after amniocentesis (Group IIa). In this group there was a 29% rate of neonatal sepsis (n=7), and amniotic fluid culture was positive in 33% of the cases. 24 delivered beyond 48 hours after amniocentesis (Group IIb). In this group there was a 21% rate of neonatal sepsis (n=5) and amniotic fluid culture was positive in 12.5% of the cases. Group I and IIa had a high risk of neonatal sepsis and could not benefit from amniocentesis culture results.

CONCLUSION

Group IIa and IIb cannot be distinguished a priori, therefore systematic amniocentesis can only have a restricted impact on the management of antibiotic therapy. Even in the case of a negative amniotic fluid culture, antibiotic therapy is mandatory. If a systematic amniocentesis policy is used, one hundred amniocentesis have to be performed in order to adapt six antibiotic therapies. In the group with the highest risk of neonatal sepsis (severe oligohydramnios), amniocentesis cannot be performed. A policy of systematic amniocentesis restricted to the cases that are not delivered within the first 48 hours could be evaluated in a prospective randomized trial. Such a policy could help in deciding whether to stop, adapt, or continue the antibiotic therapy, or to induce the delivery in case of an asymptomatic chorioamniotitis.