Variable Age group <20 20-24 25-29 30-34 >35 Marital status Single Married/Cohabiting Divorced Widow Education level None Primary Secondary Post secondary Number of sexual partner One Multiple BMC Public Health 2009, 9:437 http://www.biomedcentral.com/1471-2458/9/437 HIV screening HIV testing was done using Tanzania's National HIV rapid test algorithm [10]. SD-Bioline HIV 1/2 (SD Standard Diagnostic, Inc Korea) was used for initial screening and reactive samples were confirmed by Determine™ (Abbott Laboratory, Tokyo Japan). A sample was considered seronegative if it was non reactive at screening and serop- ositive when reactive on both assays. There were no dis- cordant samples. CD4+ T lymphocytes enumeration This was determined by using Becton Dickson FACS Cali- bur flow cytometry. Data analysis Data was analysed using SPSS for windows version 13.0 [11]. Comparison of proportions of maternal and neona- tal colonisation of GBS and statistical significance of GBS in HIV infected and non HIV infected pregnant women colonised with GBS were tested by using the Pearson's Chi-squared test (χ2). Where the numbers in a cell was less than five, a Fisher's exact test was used. P-values ≤ 0.05 were considered statistically significant. prior to enrolment. HIV- pre and post test counselling were provided to the participants according to the Tanza- nia national guidelines for HIV testing and counselling [12]. Any other requested additional information was provided to participants by study personnel. HIV positive women were offered prevention of mother to child trans- mission (PMTCT) services and also referred to HIV care and treatment clinic within MNH for further manage- ment, according to the National guidelines for Care and Treatment, Ministry of Health, Tanzania. GBS results of neonates were relayed to attending doctors for their man- agement. All participants' results were kept confidentially. Results Three hundred pregnant women (from 37 weeks of gesta- tion) and 180 neonates were enrolled in the study between October and March 2009. There was loss of fol- low up of 120 neonates, due to the fact that not all preg- nant women delivered at MNH. GBS were isolated from 69 (23%) pregnant women and from16 (8.9%) neonates. Vaginal carriage rate was higher 37 (12.3%) than rectal colonisation rate 15(5%). The proportion of GBS isolated from both sites was 17(5.7%). Ethical issues Ethical and research clearance was obtained from Muhim- bili University of Health and Allied Sciences (MUHAS) Senate Research and Publication Committee. A written informed consent was obtained from each participant Table 1 summarises the rate of GBS colonisation by social demographic characteristics. The age of the women ranged from 16-44 years with mean age of 26.6 years (SD ± 5.1). Generally, GBS colonisation did not appear to be influenced by maternal age, marital status, education level Table 1: Association between social demographic factors and GBS colonisation among pregnant women Total Number of GBS isolated Percentages P-value 26 86 107 56 25 52 244 3 1 8 145 104 43 279 21 4 19 23 18 5 10 58 1 0 3 30 28 8 65 4 15.4 22.1 21.5 32.1 20 19.2 23.8 33.3 0 37.5 20.7 26.0 20.9 23.3 19 0.43 0.74 0.54 0.65 Page 3 of 7 (page number not for citation purposes)