Independent Associations of Bacterial Vaginosis and Chlamydia trachomatis Infection With Adverse Pregnancy Outcome

Abstract

We prospectively studied the relationship of pregnancy outcome to bacterial vaginosis, an anaerobic vaginal condition, and to other selected genital pathogens among 534 gravid women. Bacterial vaginosis was presumptively diagnosed by gas-liquid chromatographic identification of microbial organic acid metabolites in 102 women (19%), and cervical infection with Chlamydia trachomatis was found in 47 (9%) of the women. Although women with and without bacterial vaginosis had similar demographic and obstetric factors, neonates born to women with bacterial vaginosis had lower mean birth weight than did neonates born to women without bacterial vaginosis (2960 +/- 847 g vs 3184 +/- 758 g). Bacterial vaginosis was significantly associated with preterm premature rupture of the membranes (odds ratio [OR], 2.0; 95% confidence interval [Cl], 1.1 to 3.7), preterm labor (OR, 2.0; Cl, 1.1 to 3.5), and amniotic fluid infection (OR, 2.7; Cl, 1.1 to 6.1), but not with birth weight below 2500 g (OR, 1.5; Cl, 0.8 to 2.0). Cervical infection with C trachomatis was independently associated with preterm premature rupture of the membranes, preterm labor, and low birth weight (OR, 1.5; Cl, 0.8 to 2.0).

Abnormal bacterial colonisation of the genital tract and subsequent preterm delivery and late miscarriage

“…Seven were found not to be pregnant; nine had elective deliveries before 37 weeks of gestation; 11 took antibiotics after bacterial vaginosis was diagnosed; three were carrying fetuses with lethal congenital malformations; 11 were carrying twins; four underwent termination of pregnancy; and 20 were lost to follow up. In calculating the size of the population to be studied we assumed an incidence of bacterial vaginosis of 5% and an incidence of premature birth of 7% and that women with bacterial vaginosis would be 3.8 times as likely to have preterm delivery as women with normal flora 8. A sample size of 1000 gives a power of 91%.…”

The association of gonorrhoea and syphilis with premature birth and low birthweight.

“…Maternal infections with Chlamydia trachomatis, Group B streptococcus, Ureaplasma urealyticum, Mycoplasma hominis, Trichomonas vaginalis, Staphylococcus aureus and bacterial vaginosis have statistical associations with adverse pregnancy outcome. [1][2][3][4][5][6] Case reports78 and case-control studies9-'1 also suggest an association of maternal gonorrhoea with premature delivery and chorioamnionitis, but prospective data are extremely scarce. 12 At least one prenatal cervical culture for Neisseria gonorrhoeae is recommended during pregnancy."…”

Infection and antibiotics in the aetiology, prediction and prevention of preterm birth

“…Other organisms have also been implicated. In a study of 534 pregnant women, cervical infection with Chlamydia trachomatis BV was independently associated with PPROM, SPTL and LBW (Gravett et al 1986). Th e presence of Gardnerella vaginalis and Ureaplasma urealyticum during the 2nd trimester increased the risk of PTB two-fold (McDonald et al 1992).…”

“…Bacterial vaginosis is characterised by a change in the microbial ecosystem of the vagina and is a risk factor for SPTL and PTB (Eschenbach 1993;Gibbs 1993;Hay et al 1994) and PROM (Gravett et al 1986;Lamont 2003a).…”

“…Th e main cohort studies from Europe, North America and the Far East (Gravett et al 1986;Kurki et al 1992;Riduan et al 1993;Hay et al 1994;McGregor et al 1994;Hillier et al 1995;Meis et al 1995;Gratacos et al 1998) and three case -control studies from the USA, Sweden and Australia (Eschenbach et al 1984;McDonald et al 1992;Holst et al 1994) have used diff erent methodologies to examine the association between abnormal genital tract fl ora, either in the form of BV or the presence of BV associated organisms, and adverse outcomes of pregnancy. Th e majority of these studies show a statistically signifi cant association between abnormal genital tract fl ora and PTB and the degree of risk was greater the earlier in pregnancy at which the abnormal fl ora was detected (Lamont et al 2004).…”