A genital tract infection during pregnancy can cross into the amniotic fluid and result in prelabour rupture of the membranes and preterm labour. Such infections include bacterial vaginosis; chlamydial, trichomonas and gonorrhoeal infections; syphilis and HIV, but not candida. Preterm birth (before 37 weeks of gestation) is associated with poor infant health and early deaths, admission of the newborn to neonatal intensive care in the first few weeks of life, prolonged hospital stay and long-term neurologic disability including cerebral palsy.
The present systematic review found that a simple infection screening and treatment program during routine antenatal care may reduce preterm births and preterm low (below 2500 g) and very low (below 1500 g) birthweights, from only one identified controlled study. The study was of high methodological quality and reported on 4155 women randomly assigned either to an intervention group where the results of infection screening were reported or a control group where the results of the vaginal smear test were not reported. The simple infection screening reduced preterm births from 5% of women in the control group to 3% in the intervention group. The number of low birthweight preterm infants and very low birthweight infants were significantly lower in the intervention group than in the control group. Neonatal morbidity or deaths in the hospitalisation period were not reported. No adverse effects were reported for the pregnant women during the treatment. Women in the intervention group who were found to have vaginal infection received standard treatment and blinding of the treatment was not possible. The obstetricians may, therefore, have provided a different level of care to women in whom an infection had been identified compared with the control group.