Oral pathogenic micro-organisms have been implicated in disease causation elsewhere in the human body especially in pregnancy where they negatively influence birth outcomes. Oral hygiene measures and treatment with appropriate antibiotics prevent this negative effect. Both periodontal diseases and negative pregnancy outcomes are common among pregnant women in Nigeria; however, oral health care is not presently an integral part of antenatal care in our environment. We investigated the types of bacteria present in the mouth of some pregnant women in Ibadan, as well as the sensitivity pattern of these organisms to commonly available antibiotics. Pre-tested questionnaires were used to obtain socio-demographic information as well as oral hygiene and pregnancy history from the participants. This was followed by an intra-oral examination during which an oral swab was taken using a sterile microscopic culturing swab stick and inoculated immediately into Thioglycollate broth. Antimicrobial susceptibility was performed on confirmed pathogens using Kirby-Bauer method. Data was entered into a computer spread sheet. Frequency tables were generated and measures of central tendency calculated. Mean age was 25.28± 4.9 years old. The most prominent oral isolates were Kliebsiella species
and these were higher in the second and third trimesters of pregnancy respectively. Anti-microbial susceptibility of isolates was highest for Ceftazidime: 263(99.6%), Rocephin: 247(98.9%), Resistance was highest to Co-trimoxazole 108(44.8%) and Tetracycline: 108(43.7%). The high prevalence of pathogenic, non-commensal isolates in the oral cavity of these women is cause for great concern. General personal as well as oral hygiene measures are proposed for the reduction and elimination of these pathogens.