We performed the retrospective analysis of the hospital archive documents to gain insights into the implementation status of the GBS neonatal disease prevention programme in our environment (the town of Osijek area, eastern Croatia). This analysis has enabled us information on barriers to the efficient implementation of this programme into practice, and indicated the areas of improvement. A lesson learned from this analysis may be used more generally, to inform the prevention and screening programmes implementation strategies. We identified three problematic areas where improvements are likely to be possible: 1) the inappropriateness of the hospital documentation for the retrospective effectiveness analyses, 2) the dyscrepancy between the customized protocol performance vs. recommendations provided by the guidelines, and 3) the difficulties in the guidelines translation into clinical practice. Regarding the appropriateness of the hospital archive documentation, we found that the storage of the archive records is supported by the ICT system only in a part of the hospital facilities. The Department of Gynaecology and Obstetrics and the Neonatal Intensive Care Unit, both departments important for this preventive programme implementation, have not been covered by the ICT system, and the only option for us, to get some relevant information, was to manually search through the archive documentation. Even when the ICT system has been installed, as in the Microbiology Department, which in organisation terms was a part of the Public Health Services, the scope of information that was possible to gain from it, was limited, and not appropriate for this purpose, which implied the need for establishing the problem-oriented documentation. For example, from the vast amount of the microbiologic findings that have been available, we could extract the list of names of women to whom the GBS swab cultures were performed in the year of examination, but it was not possible to specify the sites from which the specimens were used, or to make distinctions between the double named logs, with respect to reasons of the repeated referrals. Anyway, we had to turn to the manual searching method. The result of the documentation search in the Microbiology Department was surprising. About two thirds of the total amount of the GBS swab culture findings, that were analysed in the year 2016, were of the cervical origin (2827/3979 or 71.0%), and only a quarter (1023/3979 or 25.7%) was from the vaginal or anorectal/perineal sites, which are sites indicated in the universal neonatal Group B Streptococcal (GBS) disease prevention programme. Information that we also needed, if want to get insights into the efficiency of the GBS neonatal disease prevention programme, was the number of pregnant women in this year. We faced a new problem, by recognising that there is no specific archive book where pregnant women from the town of Osijek area are registered. Moreover, pregnant women are being dispatched at many points of the health care services, including gynecologists in the Osijek University Hospital Centre, and many individual gynaecologists working in PHC service or private facilities. We used the number of women who in 2016 had deliveries in the Osijek University Hospital Centre, as an approximate number, and for this purpose, we had to search the archive books of the Department of Gynaecology and Obstetrics. We used the number of deliveries (N = 2290) and the number of vaginal and anorectal/perineal GBS swab microbiologic findings (N = 1023) to estimate the approximate number of pregnant women who in the year 2016 were undertaken to the antenatal GBS screening programme. The estimated rate (1023/2290 or 44.7%) was lower than in the USA and some developed EU countries, where these rates were reported to be over 80% (29, 30). However, the direct comparison was difficult, because of a wide variation of protocols that have been adopted in particular countries. Moreover, in some countries, this programme has not been implemented at all (18, 31). Another area of concerns, regarding the efficient GBS screening programme implementation, was a discrepancy between the customized protocol performance vs. recommendations provided by the guidelines. As we could find out in conversation with gynecologists at the Department of Gynaecology and Obstetrics, the unusually large proportion of the cervical GBS swab tests, among the total amount of the GBS swab culture findings, could be explained by the fact that gynecologists in the town of Osijek area usually use this technique for the universal GBS screening (that is, in healthy pregnant women), probably as inertia of the high risk screening strategy. Namely, according to the Croatian national recommendations, positive cervical GBS swab tests, when found in pregnant women regardless of the reasons of referrals, are considered are indications for intrapartum antibiotics administration, even if the antenatal post treatment testing resulted negative. To assess this assumption objectively, we searched a part of the cervical GBS swab findings and their corresponding referrals. This assumption was true, due to the fact that “normal pregnancy” was the dominant diagnosis on these referrals. If taking into account this fact, that means that the GBS screening rate might have been much higher, than the primarily calculated rate of 44.7%, which was based on using only vaginal and vagino-perineal swab specimens for calculation. To assess whether gynecologists in the town of Osijek area also perform vaginal and vagino-perineal swab specimens as a part of the universal screening strategy in pregnant women, we examined a part of these findings and their referrals (613 out of a total of 1023 vaginal and vagino-perineal GBS swab findings, anylsed in the Microbiology Department, in 2016). We found that the major reason for testing the pregnant women this way, was screening on GBS vaginal colonisation. There were only a few women with the diagnosis of some pathological conditions, which was usually associated with the repeated testing. Taken together, that means, that gynecologists in our environment use both types of GBS swab specimens, cervical and vaginal/vagino-perineal, as the universal GBS screening strategies. The bias in how gynecologists perceive the guidelines recommendations may be partly due to the fact that the global, international guidelines, are not sufficiently clear in parts related to complications in pregnancy, including conditions such as diabetes, hypertension, bleeding, or multiple pregnancies. For these conditions, there are no clear recommendations for screening on maternal GBS colonisation and intrapartum antibiotic prophylaxis (25, 26, 27). These conditions are also not mentioned in the latest guidelines on prevention of the GBS early-onst disease in newborns, issued by the American College of Obstetricians and Gynecologists (14). For these conditions, gynecologists in our area regularly perform the cervical GBS swab testing and repeat it depending on the antibiotic treatment results. This custom may be a source of the guidelines misunderstanding, as they use the same tecnique for the universal screening of GBS colonisation in healthy pregnant women. Despite the problem of information extraction from the archive documents, this retrospective evaluation was useful, since it provided many details on the extent to which the GBS neonatal prevention program has been implemented in our area. When taking into account information that gynecologists, as a strategy of the GBS antenatal screening programme, use both techniques, that one based on using the cervical GBS swab culture, and that one based on using vaginal or vagino-perineal swab cultures, then the positive results of these two techniques, counting 2.76% and 4.5%, can give the approximate rate of the maternal GBS colonisation, that in our area would likely to be 6%-7%. This percentage is at a lower part of the range of 6.5% − 36%, found for European countries, and is typical for economically less developed countries (32). Another benefit of the retrospective evaluation of the hospital documentation is that this procedure has enabled identification of information which would be necessary if someone wants to analyse the effectiveness of this prevention programme implementation. We have come to the similar conclusions as some other authors, realizing that this information should include: reasons of referrals (with more details on the diagnosis, on the site where the specimen was taken from, and on whether it is the first or repeated testing, etc.), the history of antibiotics treatment during the pregnancy and the delivery, and the GBS resistance rates to antibiotics) (31). Information which would be necessary to be recorded in the ICT system, to enable the neonatal sepsis data evaluation, is the identification code, to serve as the link between the names of the mothers and their new-borns. This conclusion is based on the fact that of the total number of new-borns, who were cured for neonatal sepsis in the Neonatal Intensive Care Unit of the Osijek University Hospital Centre, in 2016, only a smal part (20 out of 148) had records on the GBS antenatal screening. There was no information on whether the result of this testing was positive or negative. The diparity between the number of mothers who were screened on GBS colonisationa and the number of those who were tested positive (5 positive out of 20 screened), implicates the possibility of the transversal infection transmission during the delivery, which justify the routine intrapartum use of PCR testing (33). Based on the number of new-borns with sepsis, and the number of women who in 2016 had deliveries, it was possible to estimate the approximate prevalence of neonatal sepsis in our area. This prevalence was 6.46%, which was similar to that in the developed EU countries, for the period for which the data in this study has been collected (34). Our main criticism on how documentation in the Neonatal Intensive Care Unit has been conducted, is on insufficient information on the infectious agents, as the causes of sepsis. For the majority of new-borns (137 out of 148, or 92.5%), the infectious agents were unknown, as they were, either not being tested, or if tested, not identified. GBS was recorded as the cause of sepsis in 7 (5%) of new-borns, but the diagnosis was established mostly on the clinical criteria. The common conclusion was that there is a need for a more systematic microbiological testing of new-borns who are suspected on neonatal sepsis, if wanting to monitor the efficiency of the neonatal GBS disease prevention programme implementation. The infectious agents other than the GBS, including E. coli, Candida albicans, and non-specified Streptococcus, were identified in only four (3%) of new-borns with sepsis. Since these infectious agents may indicate both, the late-onset sepsis, or the preterm birth, information on the time of the sepsis onset, or on whether there was the preterm delivery, or not, should be a mandatory in the Neonatal Intensive Care Unit register (33, 35).