Evidence-based Ways to Prevent Prematurity Caused by Infection

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Preterm birth (short gestation, PTB, < 37weeks) and low birth (LBW, <1500grms) continue as the commonest cause of excess perinatal morbidity, mortality and excess birth related costs and medical malpractice liabilities worldwide. Reproductive tract infection and subsequent inflammation are now recognized as common and preventable causes of short gestation and biologic immaturity at birth. Bacterial vaginosis (BV) is the best studied of microbe-mediated infections or conditions causing preterm birth. Current evidence supports these "optimizing principles" for effectively reducing risks of infection induced adverse pregnancy effects:

• Timing: Early identification and elimination/suppression of abnormal reproductive tract or genitourinary microflora is essential. Studies show that increased risks or preterm birth as well as first and second trimester causes and other adverse effects are associated with screening and positive identification of bacterial vaginosis and abnormal microflora early in pregnancy. Early treatment with elimination and/or suppression of reproductive tract infection is associated with greatest reduction of adverse effects.
• Infection and inflammation of lower and upper reproductive tract tissues are the primary pathophysiologic processes adversely affecting pregnancy. Treatments must provide for elimination/suppression of microorganism with in both upper uterine and trophoblast and lower reproductive tract tissues. Use of macrolides or clindamycin eliminates or suppresses most intrauterine microbes.
• Optimize antimicrobial choices: Choose antimicrobials which posses 1) antivirulence activities and 2) anti-inflammatory activities and are 3) concentrated within infected cells, macrolides, lincosamides.
• Combined effects, eliminate prevalent sexually transmitted infections (STIs)

Improved pregnancy outcomes are optimized when trichomoniasis, gonorrhea, and chlamydia as well as UTI/asymptomatic bacteruria are identified and treated with appropriate treatment of partners (TOPs)and tests of cure (TOC).

Conclusion: Bacterial vaginosis and other common reproductive tract microbial conditions should be 1) routinely identified, 2) treated with antimicrobials most likely to eliminate/suppress intrauterine microflora and 3) which have potentially important adjunctive advantages (antivirulence factor, anti-inflammatory, intracellular concentration and 4) which are established safe and effective in controlled trials. Selected populations appear to benefit from empiric antimicrobial therapy aimed at prevalent reproductive tract infections and at prevention or early treatment of intrauterine infection (chorioamnionitis, CAM or placentitis).

Both care providers and families can now improve pregnancy care with intelligent use of updated information about common genital tract infection. Future discussions will discuss optimized care of mothers to be who are actually having preterm labor.