LOWER GENITAL-TRACT SWABS IN THE PREDICTION OF INTRAUTERINE INFECTIONIN PRETERM PRELABOR RUPTURE OF THE MEMBRANES

Objective To examine the genital tract flora in women with preterm pre labour rupture of the membranes and to determine the relationship of t hese microorganisms to those found in fetal blood and amniotic fluid. Design Prospective study of 97 patients with preterm prelabour rupture of the membranes. Setting Maternal-fetal medicine centre. Methods Hig h vaginal and endocervical swabs were taken for routine culture of aer obic and anaerobic bacteria and Ureaplasma urealyticum and Mycoplasma hominis. Cordocentesis and amniocentesis were performed and fetal bloo d and amniotic fluid were cultured for aerobic and anaerobic bacteria. Amniotic fluid was also cultured for Mycoplasma spp. The sensitivitie s and specificities of genital tract colonisation in the prediction of fetal blood and amniotic fluid infection were calculated. Results Pos itive genital tract cultures for aerobic and anaerobic organisms predi cted 40% of positive fetal blood and 53% of positive amniotic fluid cu ltures with false positive rates of 24% and 25%. respectively. The sen sitivity and false positive rates for genital tract colonisation with Mycoplasma spp in the prediction of amniotic fluid infection with thes e organisms were 85% and 35%, respectively. Conclusions In preterm pre labour rupture of the membranes lower genital tract cultures provide p oor prediction of intrauterine infection.