Preterm birth is the major cause of perinatal mortality and morbidity worldwide. Infection/inflammation is responsible for a significant percentage of preterm birth, particularly at early gestations. A recent clinical recommendation by a guidelines group of the Danish Society of Obstetrics and Gynecology advised against the use of clindamycin for the treatment of bacterial vaginosis in pregnancy to reduce the risk of spontaneous preterm birth based on lack of evidence of efficacy. We believe that the evidence for the use of clindamycin for this indication is robust and that this recommendation was reached erroneously on the basis of flawed inclusion criteria: the inclusion of an unpublished study with poorly diagnosed bacterial vaginosis and the exclusion of an important pivotal study on the use of clindamycin in early pregnancy for the prevention of preterm birth. Had these errors been corrected, the conclusions would have been different.